METHOD FOR TRANSMITTING SWITCHED DATA PACKETS BETWEEN A CONTENTION CHANNEL (RACH) AND A RESERVE CHAN

专利摘要:
An uplink data transmission method from a TE terminal taken from a plurality of terminals to a GW gateway switches packets of data or fragments of packets between a first contention access mode and a second reservation access mode on request DAMA. Each TE needle terminal (106) the data packets or packet fragments on the RACH contention channel or on a request-reserved channel via an access to the DAMA request according to the packet size and their class of service, and information representative of the current transmission resources allocated to the RACH contention channel and the DAMA request reservation access mode, the representative information being notified to the terminals via a return channel.
公开号:FR3042087A1
申请号:FR1502051
申请日:2015-10-02
公开日:2017-04-07
发明作者:Mathieu Gineste；David Niddam；Cecile Faure；Isabelle Ulpat
申请人:Thales SA；
IPC主号:

专利说明:

Method for transmitting data packets switched between a contention channel (RACH) and a reserved channel on demand (DAMA)
The present invention relates to an optimized method for transmitting packet data or packet fragments switched between a RACH ("Random Access CHannel") tram contention channel and a demand reserved multiple demand channel (DAMA). Access).
The present invention also relates to a transmission system, configured to implement an optimized method of transmitting data packets or packet fragments, switched between a contention channel RACH and a reserved resource channel on request DAMA.
The present invention also relates to a user terminal, integrated in said transmission system, and configured to transmit data packets or packet fragments switched according to said transmission method. The invention also relates to a computer program comprising instructions which when loaded on computers of the transmission system execute the optimized method of transmission.
In general, the invention is applicable to any communications system requiring a contention transmission channel on an up link whose traffic is sporadic, dense and unpredictable, and can use for example transparent or regenerative satellites and / or terrestrial wireless connections, even cable connections.
Various methods of access to contention are known among which are the conventional ALOHA asynchronous protocol, the ALOHA temporal segmented or ALOHA derived derivative protocol and its derivatives combining the Capture effect (CE) e / or the effect of using a diversity (temporal or frequency) and a resolution of access conflicts CRD (in English Contention Resolution Diversity).
These protocols are all random protocols in which each user terminal accesses the transmission resources independently from other users. For each transmitted packet, the user waits for an acknowledgment of receipt from the recipient. If it does not receive it, it retransmits the same data with a random delay and this mechanism is iterated until an acknowledgment is received or until a maximum number of attempts have been made.
It is known to couple the use of a contention access via a contention channel RACH and the use of demand access in DAMA mode via a reserved resource channel according to this mode for sending for example from a terminal user a surplus of traffic if the capacity of access to the request in DAMA mode is not sufficient.
A first paper, an article by Dennis Connors et al., Entitled "A Quality of Service Based Medium Access Control Protocol for Real-Time Sources," Mobile Networks and Applications 1999, describes such a use coupling contention access RA and access to the DAMA application. The switching between the use of the RA mode and the use of the DAMA mode is based on the filling level of the user terminal's RA and DAMA queues to select which channel to use among the channel and the channel allocated in the mode. DAMA.
A second document, patent application EP 1 686 746 A1, also describes a use coupling of a contention access RA and an access to the DAMA request. This second document describes that at a given moment the queue of a terminal contains Q packets and a capacity reservation for K packets has been made. The first K packets of the queue will be transmitted by a DA method, using the capacity that has already been reserved; the terminal must choose between two possibilities: either to transmit the remaining Q-K packets by a CRDSA method, or to make another capacity reservation request to transmit them by a DA method. According to a preferred embodiment of the second document, at any time the terminal is in RA mode, in which case it makes capacity requests for transmission according to a request assignment method. The bit content of the queue at the execution of the packets for which a capacity reservation has already been made, indicated (QK) bits, is compared with two threshold values, a first threshold value and a second value. threshold strictly lower than the first value. If the terminal is in RA mode and (Q-K) bits goes above the first threshold, it switches to the DA mode. Conversely, if Im (QK) bits drops below the second threshold when the terminal is in DA mode, the latter goes into RA mode (but the K packets for which a reservation of capacity has been made will nevertheless be transmitted by the method DA). Thus, in this second document, the switching between the use of the RA mode and the use of the DAMA mode is also based on the filling level of the RA and DAMA queues of the user terminal to select the channel to be used among the RA channel and channel allocated in DAMA mode.
Despite the solutions proposed in the two documents and described above, the RACH contention channel is little used to transfer useful data and remains mainly used for standard access and signaling phases. logon for example), on the one hand because of the low efficiency inherent to this type of channel (typically about 25% for stable access on a RACH channel type Aloha or SA), and secondly to because of the risks of terminal entry delays in the system.
In addition, none of the current solutions, especially those described in the first and second documents can efficiently transfer small volumes of sporadic and unpredictable data.
The technical problem is to improve the transfer capacity and efficiency of a method for transmitting data packets or packet fragments, switched between a contention channel RACH and a reserved resource channel on request DAMA, when the traffic input is a traffic of small volumes of sporadic and unpredictable data. To this end, the subject of the invention is a method for upstream transmission of data packets and packet fragments from a terminal TE among a plurality of terminals to a gateway GW, the data packets or packet fragments being switched. between a first contention access mode using a RACH contention channel and a second DAMA reservation on demand access mode using a DAMA reserved channel, and the RACH contention channel being shared by the plurality of terminals; the transmission method being characterized in that it comprises the following steps: in a first step, the terminal considered TE receives almost in real time from the gateway via a downlink or information representative of the transmission resources current allocations to the RACH contention channel and the DAMA reservation-on-demand access mode; in a second step, the terminal TE routes the data packets or packet fragments on the RACH contention channel via a contention access or an on-demand reserved channel via an access to the DAMA request according to the packet size and of their class of service, and information representative of the current transmission resources allocated to the RACH contention channel and the DAMA request reservation access mode, the information representative of the current allocated transmission resources being provided and transmitted to the terminals of the plurality on a return path.
According to particular embodiments, the transmission method comprises one or more of the following characteristics: the second step comprises a third step of implementing a classification and a first referral of the packets during which the terminal classifies the packets according to their size and class of service in terms of quality of service (QoS) and routes the packets according to this classification to a first uniform set of queues connected exclusively to the access to the request, either to a second mixed set of queues connectable separately and selectively over time to one of the two accesses between the contention RA access and access to the DAMA request; the needle terminal prioritizes short data packets of low data volume corresponding to sporadic traffic on the contention channel RACH; the second step comprises a fourth step following the third step during which the packets, output from the queues of the second mixed set, are fragmented into one or more packet fragments according to the size of the packets, then the packets or fragments of packets are scheduled according to the respective priorities associated with the packets and determined by the quality of service classes of said packets, and then the packets or fragments of packets are pre-assigned through pre-information -assigning access mode, on an access mode, taken from the access mode RA and the access mode DAMA, according to the information representative of the current transmission resources allocated and a predetermined type of convergence , taken from a partial convergence and a total convergence, then packets or fragments of packets are encapsulated according to a protocol of encapsulation which depends on the type of convergence, then the packets or fragments of packets are switched on one of the two accesses taken from the contention access RA and access to the DAMA request according to the pre access mode -affected; when the convergence type is a partial convergence, the encapsulation protocol used is a conventional protocol which does not unambiguously identify the fragments of the packets, and which is transparent with respect to the gateway acting as receiver, and when the contention access mode RA has available resources, packets or fragments of packets from the second mixed set after fragmentation primarily use contention access RA; and when the contention access mode RA no longer has available resources, the packets or fragments of the packets from the second mixed set after fragmentation are redirected to the access mode to the DAMA request; and when a switch from the RA access mode to the DAMA access mode takes place, the packet or fragments of the packet being sent on the RA access mode before switching are fully retransmitted on the access to the RFSA request; when the convergence type is a partial convergence, an ARQ (Automatic Repeat reQuest) type mechanism is implemented at the level of the convergence layer implemented in the fourth step; when the convergence type is a total convergence, the encapsulation protocol used is an encapsulation protocol configured to unambiguously identify the content of each fragment of a packet from the second mixed set through a information identifying the contents of each fragment of a packet; and the access mode of each packet fragment is selected according to the next transmission opportunity on one of the two accesses, the next transmission opportunity being the time closest to the current time from the instant of the next transmission on the RACH channel, and the moment of availability of resource (s) possibly already assigned (s) on the DAMA access; when the convergence type is a total convergence, the encapsulation protocol used is: either a conventional encapsulation protocol modified in terms of the use of a signaling bit reserve, existing in a field of the protocol frame not conventionally used, either an augmented conventional encapsulation protocol in which a bit field has been added to the existing protocol bit field, or a new protocol; the information representative of the current transmission resources allocated to the RACH contention channel is obtained from a first estimated probability of receiving an empty expected burst Pe, or a pair of estimated probabilities formed by the first measured probability Pe and a second probability of receiving an empty burst Ps, or a third estimated probability of a crashed salvo Pc, the probabilities Pe alone, or Pe and Ps, or Pc alone being estimated as continuous by the gateway GW, on an observation window of predefined width and from measurements in reception in said window of observation of the expected bursts; and the third step being part of the transmission method and being executed before the first step; the information representative of the current transmission resources allocated to the contention channel RACH is comprised in the set formed by the current composition of the contention channel and / or the current list of the classes of terminals authorized to transmit and the classes of terminals not authorized to to emit; and the estimated probabilities Pe alone, or Pe and Ps, or Pc alone; and the external input load of the RACH channel estimated from the estimated probability Pe; the transmission method further comprises a method of dynamically adapting the capacity of the contention channel, the dynamic adaptation method of the capacitor being characterized in that it comprises the following steps: in a first step, the value of a desired external load as the nominal operating point of the channel, the actual external channel load being equal to the current rate of new incoming terminals transmitting a respective burst of data on the channel; in a second step, continuously estimating on an observation window of predefined width and from measurements on reception in said expected burst observation window a first measured probability of reception of an empty expected burst Pe, or a pair of measured probabilities formed by the first measured probability Pe and a second measured probability of successful reception of a burst Ps, or a third measured probability of a crashed salvo Pc; in a third step, determining, using a mathematical model or a simulation, a first upper threshold Sh and a second lower threshold Sl of a variable Gr that is monotonically sensitive to the external load of the channel contention, the external loads of the upper and lower contention channel respectively corresponding to the first upper threshold or the second lower threshold, the sensitive variable Gr depending on the first probability Pe or the third probability Pc or the pair of probabilities (Pe, Ps) and the type and parameters defining the contention access protocol; * in a fourth step, determine the current sensitive magnitude according to one or both measured probabilities; * in a fifth decision-making step, when a crossing of the first upper threshold by the current sensitive magnitude takes place one or more consecutive times away from the value of the magnitude corresponding to the nominal external load, increase the current capacity of the transmission channel by releasing additional communication resources in terms of additional frequencies and informing by a return channel the terminals of the new composition of the increased capacity transmission channel; and / or when a crossing of the second lower threshold takes place by the current sensing magnitude once or more consecutive times away from the value of the magnitude corresponding to the rated external load, decreasing the current capacity of the transmission channel by removing communication resources in terms of frequencies from the transmission resources currently available and informing the return channels of the new composition of the reduced capacity transmission channel; the transmission method further comprises a flow control method, coupled to said capacity adaptation method and comprising the following steps:. * the GW gateway provides a current list of terminal classes distinguishing the classes of the terminals authorized to transmit and the classes of terminals to which transmission is prohibited, and. * when the crossing of the first upper threshold SH causes a decision to increase the capacity of the channel and a predetermined maximum size of the channel is reached, the gateway triggers an increase in the level of flow control by prohibiting transmission to a class of terminals authorized to transmit from the current randomly selected list in the current list, updating the list of classes authorized to transmit and notifying by the return to the terminals the updated list of classes authorized to transmit; and. * When the crossing of the second lower threshold Sl induces a decision to decrease the capacity of the channel, the gateway triggers a decrease in the level of flow control by allowing the emission to a class of forbidden terminals to emit from the current list. subsequently, randomly selected from the current list, updating the list of classes authorized to transmit and notifying back to the terminals the updated list of classes authorized to be issued. The invention also relates to a system for transmitting data or fragments of packets, comprising a plurality of user terminals and a GW connection gateway to a second network, each terminal being configured to transmit to the GW gateway on an upstream channel. data packets or packet fragments, switched between a first contention access mode using a RACH split contention channel shared by the plurality of terminals and a second DAMA on-demand reservation access mode using a reserved channel on demand DAMA; the transmission system being characterized in that each terminal is configured to receive almost in real time from the gateway via a return channel one or information representative of the current transmission resources allocated to the contention channel RACH and the reservation access mode on request DAMA; and each terminal is configured to direct data packets or packet fragments over the RACH contention channel via contention access or on-demand channel through access to the DAMA request depending on the packet size and their availability. class of service, and information representative of the current transmission resources allocated to the RACH contention channel and the DAMA request-on-demand access mode, the information representative of the current allocated transmission resources being provided and transmitted to the plurality terminals on a return way.
According to particular embodiments, the transmission system comprises one or more of the following characteristics: the connection gateway GW is configured to implement the steps of continuously estimating on an observation window of predefined width and from reception measurements in said expected burst observation window a first measured probability of reception of an empty expected burst Pe, or a pair of measured probabilities formed by the first measured probability Pe and a second measured probability of successful reception of a salvo Ps, or a third measured probability of a salvo having suffered a collision Pc; determining a current magnitude Gr monotonically responsive to the external load of the contention channel RACH from the first estimated probability Pe or the third probability Pc or from the pair of probabilities (Pe, Ps) and parameters defining the protocol access to restraint; then when a crossing of a first upper threshold Sh by the current magnitude takes place one or more consecutive times away from the value of the magnitude corresponding to the nominal external load, increasing the current capacity of the transmission channel by releasing additional communication resources in terms of additional frequencies and informing on a return path the terminals of the new composition of the enhanced capacity transmission channel; and / or when a crossing of the second lower threshold SL takes place by the current sensing magnitude once or more consecutive times away from the value of the magnitude corresponding to the nominal external load, decreasing the current capacity of the transmission channel removing communication resources in terms of frequencies from the transmission resources currently available and informing the return channels of the new composition of the reduced capacity transmission channel; the gateway GW and the terminals TE are configured to implement a flow control mechanism and a congestion control mechanism through the regular and frequent provision by the connection gateway of a current list of terminal classes authorized to transmit and terminal classes not authorized to transmit. The invention also relates to a transmission terminal on a rising channel of data packets or packet fragments of packet data or packet fragments, switched between a first contention access mode using a contention channel RACH and a second DAMA reservation-on-demand access mode using a reserved channel on request DAMA, the terminal being characterized in that it comprises: a first access to contention RA and a second access to the request DAMA respectively comprising a first queue of RA standby connected to a first access output terminal RA and a second DAMA queue connected to a second output terminal (236) DAMA; and a first uniform set of queues connected exclusively to the second access to the request; and a second mixed set of queues connectable separately and selectively over time to one of the two accesses from the first contention access RA and the second access to the DAMA request; and a packet classification and first referral unit, configured to classify the packets according to their size and class of service in terms of quality of service (QoS), and to route the packets according to this classification to either the first uniform set of queues, ie towards the second mixed set of queues.
According to particular embodiments, the transmission terminal comprises one or more of the following features: the terminal further comprises a processing and convergence unit connected upstream to an input terminal of the packets at the first and second set of queues and upstream at the first and second ports, and an RA and DAMA access resource management agent connected between a signaling signal return trunk port and the processing and convergence unit; the access resource management agent being configured to: * monitor information representative of the current transmission resources available on the RACH contention channel and the access mode to the DAMA request, and. * initiate requests for resources according to the filling of the queues of the first and second sets; the processing and convergence module being configured to: * fragment the packets, outputted from the queues of the second mixed set, into one or more packet fragments according to the size of the packets, and then. packets or fragments of packets according to the respective priorities associated with the packets and determined by the quality of service classes of said packets, then. * pre-allocating the packets or fragments of packets through pre-assignment information access mode mode, on an access mode, taken from the first RA access and the second DAMA access, based on information representative of the current transmission resources allocated to RA and DAMA accesses and of a predetermined type of convergence , taken from partial convergence and total convergence, then. * encapsulate packets or packet fragments according to an encapsulation protocol that depends on type of convergence, then. * direct packets or fragments of packets to one of the two accesses taken from the RA contention access and access to the DAMA request according to the pre-assigned access mode. The invention also relates to a computer program comprising instructions for implementing the transmission method as defined above, when the program is executed by one or more processors of a transmission system as defined above. The invention will be better understood on reading the description of several embodiments which will follow, given solely by way of example and with reference to the drawings in which: FIG. 1 is a diagrammatic view of a system of FIG. transmission according to the invention, configured to implement a method of transmitting data packets or packet fragments switched between a contention channel RACH and a reserved channel in DAMA mode; FIG. 2 is a flowchart of a method according to the invention for transmitting data packets or packet fragments switched between a contention channel RACH and a reserved channel in the DAMA mode implemented by the transmission system of FIG. 1; Figure 3 is a view of the architecture of a terminal TE, integrated in the system of Figure 1 and configured to implement the transmissions method according to the invention of Figure 2; FIG. 4 is a comparative view of the signaling exchanges required for a transfer of a small volume of user data from a terminal to the gateway between a first conventional transmission configuration in which the contention RACH channel is used only in the first phase. network access and other channels of a DAMA mode are used for the actual transfer of the user data, and a second configuration using the invention in which the RACH actually transfers the user data; Figure 5 is a comparative view of delay performance between first system using only a CRDSA-type RACH contention channel for unpredictable sporadic traffic transmission and a second DVB-RCS2 system using DA-mode reserved channels. . Figure 6 is a flow chart of a particular embodiment of the transmission method of Figure 2; The invention is described below with reference to a satellite communications system in which a plurality of users, each having a user terminal own TE (in English "Terminal Equipment"), are connected via a "multi-beam" ("bent pipe") satellite with G gateways (GateWays) allowing access to a terrestrial network. This does not limit the scope of the invention which can be applied to different communications systems using, for example, regenerative satellites and / or terrestrial wireless connections, or even cable connections.
According to FIG. 1, a satellite communications system 2, configured to implement the invention, comprises a number n of terrestrial user terminals TE-i, TE2, .... TEn, only three terminals 4, 6, 8 corresponding to the respective designations TE-i, TE2, TEn being shown in Figure 1 for the sake of simplicity, a connection gateway 12 to a second network 14 such as the Internet, and a satellite 16 SAT.
The satellite 16 comprises a payload 18 transparent or regenerative edge processing that serves as a relay between the terminals 2, 4, 6 and the gateway connection 12. The terminals 4, 6, 8 are each configured to transmit in the form of bursts data packets or fragments of packets to the connection gateway 12 by selectively switching the bursts between a first access mode using a contention channel 20, designated Random Access Channel (RACH), and a second Demand Assigned Mode Access (DAMA) mode using an on-demand channel 22. The RACH contention channel 20 and the on-demand channels 22 form an uplink 24, broken down into a first uplink 26 from the terminals 4, 6, 8 to the satellite 16 and a second uplink 28 from the satellite 16 to the connection gateway 12.
A signaling return downlink 34 is used to send from the connection station 12 to the terminals 4, 6, 8 one or more information representative of the current transmission resources allocated to the contention channel RACH and the access mode to reservation on request DAMA.
The downlink 34 is broken down into a first downlink 36 from the connection station 12 to the satellite 16 and a second downlink 38 from the satellite 16 to the terminals 4, 6 and 8.
Preferably, when the traffic distribution strategy aims to minimize the number of resources allocated globally to the contention channel 20 and the reserved channels 22, and thus to maximize the use of the contention channel for the packets, the method described in the patent application entitled "Dynamic adaptation method of the capacity of a contention transmission channel" and filed together with the present application, is used.
In this case, the connection gateway 12 is configured to receive and demodulate with the aid of a gateway receiver 30 bursts of data packets or fragments of packets transmitted by the terminals 4, 6, 8 on the RACH channel. transmission channel 20 or reserved channels 22 in DAMA mode.
The connection gateway 12 is also configured to dynamically adapt the capacity of the contention channel RACH and the total capacity of the reserved channels 22 in DAMA mode according to an unpredictable incoming terminal traffic and a traffic distribution strategy. between the first RA mode and the second DAMA mode. The dynamic adaptation is implemented through processing steps, performed by a gateway processing unit 32, and a regular and continuous notification step to all terminals 4, 6, 8 of the composition. resources of the first RA mode allocated to the contention channel 20 and resources of the second DAMA mode allocated to the reserved channels 22, the notification being made through a return channel 34 requiring a low capacity. When terminal classes are defined, a flow control mechanism can be implemented by regular and continuous notification to all terminals 4, 6, 8 and in addition to an updated list of authorized terminal classes. to be sent by the gateway.
In general, each terminal 4, 6 and 8 comprises a transceiver 40 and a terminal processing unit 42, configured to receive the management information of the contention channel RACH and the reserved channels 22 in the DAMA mode, sent by the connection station 12 on the downlink 34, and to exploit this information.
Alternatively and in addition to the implementation of an optional flow control mechanism, coupled to the dynamic matching method of the RACH transmission channel capability, the terminals 4, 6, 8 are configured to implement a channel congestion control mechanism in which the spreading of the retransmission delays of the terminals authorized to transmit is an increasing function of a flow control level representative of the degree of congestion of the channel.
The RACH contention channel uses a halftone or asynchronous contention protocol.
The raster containment protocol is for example included in the set formed by the ALOHA temporal or halftone segmentation protocol (in English Slotted ALOHA) and its derivatives combining the Capture Effect (C Capture Effect) and / or the effect of using a diversity (temporal or frequency) and a resolution of contention resolution diversity (CRD) access conflicts.
An asynchronous contention protocol is for example an ESSA protocol (in English Enhanced Spread Spectrum ALOHA) or a SMIM protocol (in English "S-band Mobile Interactive MultiMedia").
According to Figure 2 and in general, a method for forwarding 102 packet data or packet fragments from a TE terminal taken from a plurality of terminals to a GW gateway is implemented, for example, by the system. described in Figure 2.
The data packets or packet fragments are switched between the first contention access mode using the RACH dither channel and the second DAMA on-demand access mode using an on-demand channel 22.
The RACH contention channel 20 is shared by the plurality of terminals 4, 6, 8.
The transmission method 102 includes a first step 104 followed by a second step 106.
In the first step 104, the considered terminal TE receives almost in real time from the connection gateway 12 via the return channel 34 or information representative of the current transmission resources allocated to the contention channel RACH and the reservation access mode on request DAMA.
Then in the second step 106, the considered terminal TE needle data packets or packet fragments on the RACH contention channel via contention access of the terminal or on a request-reserved channel 22 via access to the DAMA request. the terminal according to the packet size and their class of service, and information representative of the current transmission resources allocated to the RACH contention channel and the DAMA on-demand reservation access mode. The information representative of the current allocated transmission resources is provided and transmitted to the terminals 4, 6, 8 of the plurality on the return channel 34.
According to the approach of the invention and contrary to what is conventionally proposed, the explicit or implicit state of the contention access channel 20 in terms of a magnitude representative of the external load of the RACH channel is taken into account to transmit useful traffic (different from the signaling specific to the transmission) primarily on this channel 20 and more efficiently in terms of use of the resource than on the channel 22 reserved for the request in the second mode DAMA .
Here and contrary to what is conventionally proposed, the filling level of the queues of the terminal is not used. Here, the level of charge and / or congestion of the contention channel 20, transmitted implicitly or explicitly by the connection gateway 12 and received by the terminals, is used primarily and predominantly.
This new approach is particularly suitable for transmitting part or all of sporadic and unpredictable traffic which is generally and conventionally sent in DAMA mode or in "circuit" mode.
This new approach makes it possible to avoid reservation and immobilization of resources in circuit mode for a long time, to avoid in DAMA mode a signaling volume and a significant associated delay as well as a sub-optimal use of potential resources, while we try to transmit one or a few useful data messages, often a single message.
The second step 106 includes a third step 108 followed by a fourth step 110.
The third step 108 is a step of classifying and first routing the packets during which the TE terminal classifies the packets according to their size and class of service in terms of quality of service (QoS). The terminal TE then routes the packets according to this classification, either to a first uniform set of queues connected exclusively to access to the request, or to a second mixed set of separately connectable and selectively connectable queues. time to one of the two accesses taken from access to RA contention and access to the DAMA request.
The fourth step 110, subsequent to the third step 108, is a step during which the packets, outputted from the queues of the second mixed set, are fragmented 112 into one or more fragments of packets depending on the size. some packages. Then, in the same step 110 the packets or packet fragments are scheduled 114 according to the respective priorities associated with the packets and determined by the quality of service classes of said packets. Then, the packets or packet fragments are pre-assigned 116 through access mode pre-assignment information, on an access mode, taken from the access mode RA and the mode of access. DAMA access, based on information representative of the current allocated transmission resources and a predetermined type of convergence, taken from partial convergence and total convergence. Then, the packets or fragments of packets are encapsulated 118 according to an encapsulation protocol which depends on the type of convergence. Then, packets or fragments of packets are routed 120 on one of the two accesses taken from the contention access RA and access to the DAMA request according to the pre-assigned access mode.
Two types of convergence, partial convergence and total convergence can be implemented. The choice of the type of convergence depends on the communications system under consideration and the envisaged strategy regarding the complexity and efficiency of the use of transmission resources.
In both cases, a terminal-side information representative of the load level and / or congestion of the contention access is used so as not to congest the TACH channel which remains reserved in priority to the signaling, generally the "logon". ".
In the first case of a partial convergence, a limited modification of the access is necessary and a transparency for the protocol stacks is respected. The partial convergence layer is defined to enable the selection and priority transmission on the RACH contention channel of appropriate messages such as sporadic service messages, short messages or messages with certain traffic requirements. If the transmission on the contention channel fails or if the congestion level of the RACH is too high, the messages are then transmitted on a reserved channel in DAMA access mode. This partial convergence layer is positioned upstream of the two access types (RA and DAMA) and below the network layer, but remains relatively transparent for the data link level (encapsulation, fragmentation / reassembly). The transmission efficiency conferred by this type of convergence is not maximal for this type of convergence. However, this partial convergence can already significantly improve the use of resources of current communications systems and does not require modification of existing protocol stacks but only the addition of the convergence layer on the terminal side.
In the second case of total convergence, a common management of the two AR and DAMA accesses is realized. This approach allows a great flexibility of use of the two RA and DAMA accesses and an optimal use of the transmission resources according to the availability of these and the quality of service (QoS) requirements of the communications. For this, the preferred messages to be transmitted in RA mode are selected based on the traffic characteristics and its quality of service (QoS) requirements. If such messages exist, some of this traffic may be transmitted in the first access mode RA and another part of the traffic in the second access mode DAMA depending on the availability of the transmission resources in each access and the priority of the traffic.
Both types of convergence use an identical terminal architecture described in Figure 3.
According to this architecture, each terminal TE, 4, 6, 8, here a generic terminal 202 being represented, comprises a first access 204 contention RA and a second access 206 to the request DAMA, a first set 208 uniform queues 210, 212, 214, a second mixed set 218 of queues 220, 222, 224, a unit 228 for classifying and first routing the packets.
The first port 204 and the second port 206 respectively comprise a first queue RA 230, connected to a first access terminal 232 RA access, and a second queue DAMA 234, connected to a second output terminal 236 DAMA.
The queues 210, 212, 214 of the first uniform set 208 are connected exclusively to the second access 206 on demand.
The queues 220, 222, 224 of the second mixed assembly 218 are connectable separately and selectively in time to one of the two accesses 204, 206 taken from the first access 204 contention RA and the second access 206 to the request DAMA. The classification and first-level packet leveling unit 228 according to the OSI layer model or L3 packets, is configured to classify the L3 packets according to their size and class of service in terms of quality of service ( QoS), and route the packets according to this classification either to the first uniform set 208 of the queues 210, 212, 214, or to the second set 218 mixed queues 220, 222, 224.
Regardless of the type of convergence used, traffic classification is based on traffic characteristics (sporadicity, packet sizes) and its Quality of Service requirements. Thus, the level 3 packets are routed either to the queues 210, 212, 214 of the first set 208 associated with the channel at the request only of the second access 206, or to the queues 220, 222, 224 of the second set to access both access to the request and contention. Within the second set 218 of mixed queues, a classification of L3 packets can be performed to redirect these packets to a queue associated with a specific class of service.
A separate classification can be implemented in the case of partial convergence or total convergence. Indeed, given the greater flexibility of access in the case of total convergence, a greater part of the traffic can be directed towards the mixed part (contention and demand access queues) if it makes sense in resource terms allocated to the contention access channel.
The terminal 202 also comprises a processing and convergence unit 242 and an RA and DAMA access resource management agent 244. The processing and convergence unit 242 is connected upstream to an input terminal 248 of the L3 packets at the first and second sets 208, 218 of queues and downstream at the first and second ports 204, 206. The RA and DAMA access resource management agent 244 is connected between a signaling signal receiving return signal port 252 and the processing and convergence unit 242. The access resource management agent 244 is configured to : * monitor information representative of the current transmission resources available on the RACH contention channel and the DAMA request access mode, and. * initiate resource requests based on filling the queues of the first. and second sets 218 and 208.
The processing and convergence module 242 is configured to: * fragment the L3 packets, delivered at the output of the queues of the second mixed set, into one or more packet fragments as a function of the size of the packets L3, and then. scheduling the packets or fragments of packets according to the respective priorities associated with the packets and determined by the quality of service classes of said packets, then pre-allocating the packets or fragments of packets through a packet information. pre-assigning access mode, on an access mode, taken from the first RA access and the second DAMA access, based on information representative of the current transmission resources allocated to RA and DAMA accesses and of a type predetermined convergence, taken from partial convergence and total convergence, and then encapsulating packets or fragments of packets according to an encapsulation protocol which end of the convergence type, then. * direct packets or packet fragments to one of the two accesses from contention access RA and access to the DAMA request according to the pre-assigned access mode . The on-demand resource management agent RA 244, which monitors transmission resources and initiates resource requests when necessary, has a substantially identical functional and physical architecture for both types of convergence. It centralizes all information related to the availability of resources on both accesses 204 and 206 such as the level of flow control and congestion on the contention channel RACH and the resource allocations on the second access mode DAMA. It performs the resource requests based on the filling of the convergence layer queues and a predetermined resource allocation or allocation cycle.
The operations of the processing and convergence unit 242 and the resource management agent 244 are different depending on the type of convergence used.
When the type of convergence is a partial convergence, the encapsulation protocol used is a conventional protocol which does not unambiguously identify the fragments of the packets, and which is transparent with respect to the gateway acting as a receiver.
In this case, when the contention access mode RA has available resources, the packets or fragments of packets from the second mixed set after fragmentation primarily use contention access RA.
When the contention access mode RA no longer has available resources, the packets or fragments of the packets from the second mixed set after fragmentation are redirected to the access mode to the DAMA request.
In addition, when a switching from the RA access mode to the DAMA access mode takes place, the packet or fragments of the packet being sent on the RA access mode before switching are fully retransmitted on access to the DAMA application.
In this case, the encapsulation part is identical to the existing conventional encapsulations called "legacy", which allows the partial convergence to be completely transparent with respect to the GW connection station, considered as the receiver of the forward link.
The selection of the access for the traffic coming from the mixed queues of the second mixed set 218, that is to say the traffic which can use a demand access or an access to contention indifferently, takes into account the availability of the resource for both accesses it obtains from the Resource Management Officer). This traffic is directed and sent on the RACH contention channel if the transmission resource is available on that channel. If the resource on the contention channel is not or is no longer available, due to a notification received by the terminal TE that the flow control and / or congestion control are activated for example, the traffic is redirected to the reserved channel according to the second demand access mode. The packet which could not then be transmitted in full on the RACH channel, that is to say all the fragments of this packet, must be retransmitted completely on the channel reserved for the request.
Optionally, if an ARQ mechanism is not implemented at the application level or at level 2 and according to the required transmission quality and the level of modification tolerated in the receiver, an ARQ mechanism (Automatic Repeat reQuest) is added and implemented at the same time. level of the convergence layer implemented in the fourth stage. The addition of a simple protocol for segmentation and reassembly in RA mode makes it possible to transport the data of a user in "unconnected" mode by implementing, for example, a mechanism of the "sending and waiting for acknowledgment" type. with a unit window corresponding to the transmission of a message per message, and providing at least on the uplink a unique identifier of the transmitter, the message number, the numbers of the segments of the data to be transmitted. On good reception, the receiver, that is to say the GW gateway, responds to the transmitter, that is to say the TE terminal, via a common channel broadcast type sending as information: the identifier of the sender, the message number and the list of segments of a message received and not received. A segment can be retransmitted if it has not been correctly received by the GW receiver.
The protocol described above also allows the transport of access control messages, for example resource request messages, maintenance of the RACH channel.
When the type of convergence is a total convergence, the encapsulation protocol used is an encapsulation protocol configured to unambiguously identify the content of each fragment of a packet from the second mixed set 218 through a piece of information. identifying the contents of each fragment of a packet. The access mode of each packet fragment is selected according to the next transmission opportunity on one of the two RA and DAMA accesses. The next transmission opportunity is the moment closest to the current moment from the moment of the next broadcast on the RACH channel, and the time of provision of resource (s) possibly already assigned (s). on DAMA access. The instant of the next transmission on the RACH channel is defined from one or more delays T1, T2, one of them being drawn randomly according to a predetermined law of draw, and the parameterization of this law being able to depend on the state of the classes of terminals authorized to transmit. A procedure for defining the times of transmission by a terminal on the RACH channel is described, for example, in the patent application EP 2787702 A1 or in the patent application entitled "Process for dynamic adaptation of the capacity of a transmission channel". and filed together with this application.
An encapsulation complement is required to take into account the concurrent transmission on both RA and DAMA second mode accesses, which implies the implementation of an equivalent encapsulation layer on the receiver. ie at the GW gateway.
The selection of the access coming from the mixed queues of the second set is carried out in this case only according to the next opportunity of transmission on one of the two accesses, which can be alternatively on one or the other of the channels to the modes of different access. Unlike partial convergence, a packet can be transmitted in part on contention access and partly on access to the request. The segmentation and reassembly layer takes into account the two different modes of access in order to unambiguously identify the contents of a packet fragment to be transmitted by the transmitter of the terminal TE and reassemble the data correctly by the station. GW connection. Thus, one or more fragments of a packet may use the RA channel while the remaining fragments of the same packet may use the DAMA channel with bursts sizes that may be different from those of the RACH channel.
When the type of convergence is a total convergence, the encapsulation protocol used may be: either a conventional encapsulation protocol modified in terms of the use of a signal bit reserve, existing in a field of the frame of the conventionally unused protocol, either an augmented conventional encapsulation protocol in which a bit field has been added to the existing protocol bit field, or a new protocol.
According to FIG. 4, a first conventional configuration 352 for transmitting or transferring data between a TE terminal and a GW gateway uses a first contention RACH channel and a second DAMA mode channel, coupled to the first RACH channel and generally comprises four steps or phases.
In a first phase 354, the terminal TE accesses the network via the contention RACH channel, defined by a temporal segmentation logical frame and shared between users, and waits as a response of a CCCH notification channel (English Common Control Channel). at least one minimum resource resource allocation.
Then, in a second phase 356, the terminal TE requests dedicated resources (DAMA mode) via the DCCH control channel (English Dedicated Control Channel) allocated to it in the first phase 354 to dispose of the data which may be data. useful data of a user service but also signaling and / or control of the transmission system such as synchronization data, power control, etc.
Then, in a third phase 358, the TE terminal transfers the useful volume of data to the GW gateway on the allocated resources, in this case a Dedicated Traffic Channel (DTCH), allocated in the second phase 356 on the CCCH notification channel.
Then in a fourth phase 360, the DCCH and DTCH resources allocated in the first and second phases 354, 356 are released at the end of the transfer.
The DCCH control channel is generally dedicated on a circuit multiplexed between the TE terminals
The resources allocated are: either in DAMA mode (mainly the case), or in PAMA mode or "circuit" possibly multiplexed.
This first data transfer configuration 352 can be used and is used to transfer small amounts of data.
Typical applications that require a small amount of data are, for example, the collection type, telemetry / sensors, alarms, SMS equivalents. Another application may also be MAC / DAMA signaling (capacity request, maintenance-synchronization, etc.).
This first data transfer configuration 352 is inefficient for transferring small volumes of sporadic data. Indeed, the ratio of the useful data volume to the total volume of resources allocated and the useful transfer time to the total session time are small for this configuration.
A second configuration 372, described in Figure 4, is proposed to overcome this inefficiency. The second data transfer configuration 372 advantageously exploits the flexibility of updating the capacity of the RACH channel provided by the RACH channel capacity adaptation method in order to directly transfer the data on this RACH channel, thus maximizing the instantaneous capacity required without collapsing the channel, and minimizing useful resources and transfer session times.
The user's data is then segmented into a few rising bursts by the TE terminal and reassembled by the GW gateway. A light non-connected protocol between the TE terminal and the GW gateway is implemented in order to retransmit any data segments (such as "list received / not received" segments) when a bursts collision occurs. . The number of rising bursts required depends directly on the size of the payload of one according to the performance of the waveform used in terms of eg guard time, modulation / coding.
Considering, for example, two rising bursts useful for distributing the data of a user TE, the dimensioned exchange diagrams for the transfer of these two useful bursts make it possible to determine a first gain factor in terms of useful resources equal to about two (2 , 25 bursts for the second configuration instead of 5.12 bursts for the first configuration), and a second gain factor in terms of useful transfer time equal to about four when a geostationary satellite is used.
According to Figure 5, the performance in terms of transfer delay of a full page in the format of the Internet http protocol compared to the number of terminals registered in the system are compared between a first system using only a CRDSA type RACH contention channel. with a congestion control and a second system DVB-RCS2 (in English Digital Video Broadcast - Return Channel 2nd Generation) using reserved channels in DA mode when the input traffic is unpredictable sporadic internet traffic.
A first curve 392 represents the evolution of the transfer delay of a full page internet http as a function of the number of terminals registered in the case of the use of the first transmission system.
A second curve 394 represents the evolution of the transfer delay of a full page internet http based on the number of terminals registered in the case of the use of the second transmission system.
Figure 5 shows that the transfer delay is substantially reduced by almost half for a load of 350 terminals, or about 40% of channel utilization, when a CRDSA-type contention access channel is used at the same time. instead of a reserved access channel in DAMA mode.
The information representative of the current transmission resources allocated to the RACH dither channel can be obtained from a first estimated probability of receiving an empty expected burst Pe, or a pair of estimated probabilities formed by the first measured probability. Pe and a second probability of successful reception of a salvo Ps, or a third estimated probability of a salvo having suffered a collision Pc.
The probabilities Pe alone, or Pe and Ps, or Pc alone are estimated continuous by the gateway GW, on an observation window of predefined width and from measurements in reception in said window of observation of the bursts expected during a step executed before the first step.
The information representative of the current transmission resources allocated to the contention channel RACH is comprised in the set formed by: the current composition of the contention channel and / or the current list of the terminal classes authorized to transmit and the unauthorized terminal classes to emit ; and the estimated probabilities Pe alone, or Pe and Ps, or Pc alone; and the external input load of the RACH channel estimated from the estimated probability Pe.
According to Fig. 6 and a particular embodiment 402 of the transmission method 102 described in Fig. 2, the forward path transmission method 402 of data packets or packet fragments comprises the same first, second, third, fourth steps. 104,106, 108, 110 than those of the method 102 and further comprises, coupled to the second step 106, a dynamic adaptation method 404 of the capacity of the RACH contention channel. The dynamic adaptation method 404 of the RACH channel capacity is described with variants in the patent application entitled "Dynamic adaptation method of contention transmission channel capacity" and filed together with the present application.
The dynamic adaptation method 404 comprises a set of next steps
In a fifth step 406, the value of a desired external load is set as the nominal operating point of the RACH, the actual external channel load being equal to the current rate of new incoming terminals transmitting a respective burst of data on the channel.
Then, in a sixth step 408, the connection gateway GW continuously estimates on an observation window of predefined width and from measurements in reception in said expected burst observation window a first measured probability of reception of a expected empty burst Pe, or a pair of measured probabilities formed by the first measured probability Pe and a second measured probability of successful reception of a burst Ps, or a third measured probability of a crashed salvo Pc.
In a seventh step 410, using a mathematical model or a simulation, a first upper threshold Sh and a second lower threshold SL of a magnitude Gr, monotonically sensitive to the external load of the contention channel RACH are determined. The external loads of the upper and lower contention channel respectively correspond to the first upper threshold or the second lower threshold, and the sensitive variable Gr depends on the first probability Pe or the third probability Pc or the pair of probabilities (Pe, Ps) and parameters defining the contention access protocol.
Then in an eighth step 412, the current sensitive magnitude is determined based on one or both probabilities measured.
Then, a ninth decision-making step 414 is executed by the connection station.
When a crossing of the first upper threshold Sh by the current sensitive quantity takes place once or several consecutive times away from the value of the quantity corresponding to the nominal external load, the connection gateway GW increases the current capacity of the channel by releasing additional communication resources in terms of additional frequencies and by informing the terminals of the new composition of the enhanced capacity transmission channel by a return channel.
When a crossing of the second lower threshold S1 takes place by the current sensitive variable one or more consecutive times away from the value of the magnitude corresponding to the nominal external load, the gateway GW decreases the current capacity of the RACH transmission channel by removing communication resources in terms of frequencies from the transmission resources currently made available and by informing the return channel of the terminals of the new composition of the transmission channel with reduced capacity.
The transmission method 402 comprises on the forward path of data packets or packet fragments further comprises a flow control method 420, coupled to said dynamic matching method 404 of capacity.
The flow control method 420 comprises a set of following steps.
In a tenth step 422, the gateway GW provides a current list of terminal classes distinguishing the classes of the terminals authorized to transmit and the classes of the terminals to which transmission is prohibited.
Then in an eleventh step 424, when the crossing of the first upper threshold SH causes a decision to increase the capacity of the channel and a predetermined maximum size of the channel is reached, the gateway triggers an increase in the level of flow control by prohibiting transmitting to a class of terminals authorized to transmit from the current randomly selected list in the current list, updating the list of classes authorized to transmit and notifying back to the terminals the updated list of authorized classes to emit.
When the crossing of the second lower threshold Sl induces a decision to decrease the capacity of the channel, the gateway triggers a decrease in the level of flow control by authorizing the transmission to a class of forbidden terminals to issue from the current list suite, chosen randomly in the current list, updating the list of classes authorized to transmit and notifying back to the terminals the updated list of classes that are allowed to be transmitted.
An example of application of the invention is the transmission of an IRIDIUM (short burst data IRIDIUM) SBD type of traffic on the contention access channel which must make it possible to considerably reduce the resource used on the return channel ( circuit mode for the duration of the transaction) and the message transmission delay.
In general, the method and the transmission system according to the invention described above can be used for all sporadic traffic such as M2M traffic (in English "Mobile to Mobile") and aeronautical communication (comaero), and improve performance and Im efficiency of resource utilization.
It should be noted that the use of a partial convergence allows a significant gain in performance by requiring only a modification of the terminal software by the addition of a convergence layer. The deployment can also be staggered and realized only in the new terminals.
It should be noted that in addition to the flow control method 420 and in a coupled manner, a congestion control method can be added by being implemented at the terminals.
Advantageously, by using contention access as a priority for the transmission of unpredictable sporadic data traffic (in addition to signaling), depending on the availability of the RACH contention channel, a better efficiency of the use of the transmission resource as well as a better Quality of Service for this traffic are assured.
In addition, when the resource of is not available or is no longer available and access to the request can be used to transmit this traffic, the use of a partial convergence requires only modifications at the terminal, and allows scaled deployment of total convergence in the system.
Full integration of contention and DAMA access is achieved in the case of total convergence where the choice of access is based in real time on the availability of the resource on both channels.

权利要求:
Claims (18)
[1" id="c-fr-0001]
CLAIMS .1 Method for uplink transmission of data packets or fragments of packets from a TE terminal among a plurality of terminals (4, 6, 8) to a gateway (12) GW, the data packets or packet fragments being switched between a first contention access mode using a RACH contention channel (20) and a second DAMA on demand reservation access mode using a DAMA reserved channel, and the RACH contention channel (20) being shared by the plurality of terminals (4, 6, 8, 202); the transmission method being characterized in that it comprises the following steps: in a first step (104), the considered terminal TE receives almost in real time from the gateway (12) via a downlink (34) one or more information representative of the current transmission resources allocated to the contention channel (20) RACH and the reservation-on-demand access mode DAMA; in a second step (106), the terminal (4, 6, 8; 202) TE routes the data packets or packet fragments over the contention channel (20) RACH via contention access or reserved channel upon request (22) via access to the DAMA request based on the packet size and class of service, and information representative of the current transmission resources allocated to the RACH contention channel and the DAMA on-demand reservation access mode. The information representative of the current allocated transmission resources is provided and transmitted to the plurality of terminals (4, 6, 8) over a return channel (34).
[2" id="c-fr-0002]
A method for forward-forward transmission of data packets or packet fragments according to claim 1, wherein the second step comprises a third step (108) of implementing classification and first routing of the packets. during which the terminal classifies the packets according to their size and class of service in terms of quality of service (QoS) and routes the packets according to this classification to a first uniform set of connected queues exclusively on demand access, ie towards a second mixed set of queues connectable separately and selectively in time to one of the two accesses taken from access to contention RA and access to the request DAMA .
[3" id="c-fr-0003]
A method for forward-forward transmission of data packets or packet fragments according to any of claims 1 to 2, wherein the terminal (202) prioritizes short data packets of low data volume corresponding to a sporadic traffic on the RACH containment channel.
[4" id="c-fr-0004]
A method for forward-forward transmission of data packets or packet fragments according to any one of 2 to 3, wherein the second step (106) comprises a fourth step (110) subsequent to the third step (108). wherein the packets, outputted from the queues of the second mixed set, are fragmented (112) into one or more packet fragments as a function of packet size, and then packets or packet fragments are scheduled (114) according to the respective priorities associated with the packets and determined by the quality of service classes of said packets, and then the packets or packet fragments are pre-allocated (116) through pre-assignment information of access mode, on an access mode, taken from the access mode RA and the access mode DAMA, according to the information representative of the current transmission resources allocated and a type of access e predetermined convergence, taken from a partial convergence and a total convergence, then packets or fragments of packets are encapsulated (118) according to an encapsulation protocol which depends on the type of convergence, then packets or fragments of packets are switched (120) on one of the two accesses taken from the RA contention access and access to the DAMA request according to the pre-assigned access mode.
[5" id="c-fr-0005]
A method for forward-forward transmission of data packets or packet fragments according to claim 4, wherein When the convergence type is a partial convergence, the encapsulation protocol used is a conventional protocol which does not identify unambiguously the fragments of the packets, and which is transparent with respect to the gateway acting as a receiver, and When the contention access mode RA has available resources, the packets or fragments of packets from the second set mixed after fragmentation primarily use access to contention RA; and when the contention access mode RA no longer has available resources, the packets or fragments of the packets from the second mixed set after fragmentation are redirected to the access mode to the DAMA request; and when a switching from the RA access mode to the DAMA access mode takes place, the packet or fragments of the packet being sent on the RA access mode before switching are fully retransmitted on the access to the DAMA application.
[6" id="c-fr-0006]
A method for forward-forward transmission of data packets or packet fragments according to claim 5, wherein when the convergence type is a partial convergence, an ARQ (Automatic Repeat reQuest) type mechanism is implemented at the convergence layer implemented in the fourth step.
[7" id="c-fr-0007]
A method for forward-forward transmission of data packets or packet fragments according to claim 3, wherein when the convergence type is a total convergence, the encapsulation protocol used is an encapsulation protocol configured to identify unambiguously the content of each fragment of a packet from the second mixed set through information identifying the content of each fragment of a packet; and the access mode of each packet fragment is selected according to the next transmission opportunity on one of the two accesses, the next transmission opportunity being the time closest to the current time from the instant of the next transmission on the RACH channel, and the moment of availability of resource (s) possibly already assigned (s) on the DAMA access.
[8" id="c-fr-0008]
A forward path transmission method of data packets or packet fragments according to claim 7, wherein when the convergence type is a total convergence, the encapsulation protocol used is either a modified conventional encapsulation protocol. in terms of the use of a signaling bit bank, existing in a field of the conventionally unused protocol frame, ie an augmented conventional encapsulation protocol in which a bit field has been added to the existing bit field protocol, a new protocol.
[9" id="c-fr-0009]
A forward path transmission method of data packets or packet fragments according to claim 1 to 8, wherein the information representative of the current transmission resources allocated to the RACH contention channel is obtained from a first estimated reception probability. an empty expected burst Pe, or a pair of estimated probabilities formed by the first measured probability Pe and a second probability of receiving an empty burst Ps, or a third estimated probability of a burst having undergone Pc collision; the probabilities Pe alone, or Pe and Ps, or Pc alone being estimated continuous by the gateway GW, on an observation window of predefined width and from measurements in reception in said window of observation of the expected bursts; and the third step being part of the transmission method and being executed before the first step.
[10" id="c-fr-0010]
A forward path transmission method of data packets or packet fragments according to any one of claims 1 to 9, wherein the information representative of the current transmission resources allocated to the RACH contention channel is included in the set. formed by the current composition of the contention channel and / or the current list of permissible terminal classes and unauthorized terminal classes to be transmitted; and the estimated probabilities Pe alone, or Pe and Ps, or Pc alone; and the external input load of the RACH channel estimated from the estimated probability Pe.
[11" id="c-fr-0011]
A method of uplink transmission of data packets or packet fragments according to any one of claims 1 to 10, further comprising a dynamic adaptation method (404) of contention channel capacity, the method dynamic capacity matching device (404) characterized by comprising the steps of: in a first step (406) setting the value of a desired external load as the nominal operating point of the channel the actual external channel load being equal to the current rate of new incoming terminals transmitting a respective burst of data on the channel; in a second step (408), continuously estimating on an observation window of predefined width and from measurements on reception in said expected burst observation window a first measured probability of receiving an expected empty burst Pe, or a pair of measured probabilities formed by the first measured probability Pe and a second measured probability of successful reception of a burst Ps, or a third measured probability of a crashed salvo Pc; in a third step (410), determining using a mathematical model or a simulation, a first upper threshold SH and a second lower threshold S | _ of a variable Gr that is monotonically sensitive to the external load of the contention channel, the external loads of the upper and lower contention channel respectively corresponding to the first upper threshold or the second lower threshold, the sensitive variable Gr depending on the first probability Pe or the third probability Pc or the pair of probabilities (Pe, Ps) and the type and parameters defining the contention access protocol; in a fourth step (412), determining the current sensitive magnitude according to one or both measured probabilities; in a fifth decision-making step (414), when a crossing of the first upper threshold by the current sensitive variable takes place once or more consecutive times away from the value of the magnitude corresponding to the nominal external load, to increase the current capacity of the transmission channel by releasing additional communication resources in terms of additional frequencies and by informing the terminals of the new composition of the enhanced capacity transmission channel by a return channel; and / or when a crossing of the second lower threshold takes place by the current sensing magnitude once or more consecutive times away from the value of the magnitude corresponding to the rated external load, decreasing the current capacity of the transmission channel by removing communication resources in terms of frequencies from the transmission resources currently available and by informing the return channels of the new composition of the reduced capacity transmission channel.
[12" id="c-fr-0012]
A forward path transmission method of data packets or packet fragments according to claim 11, further comprising a flow control method (420), coupled to said capacity matching method (404) and which comprises the the following steps: .- the gateway provides (422) a current list of terminal classes distinguishing the classes of terminals authorized to transmit and the classes of terminals to which transmission is prohibited, and .- when the crossing of the first upper threshold SH causes a decision to increase the capacity of the channel and a predetermined maximum size of the channel is reached, the gateway triggers (424) an increase in the level of flow control by prohibiting transmission to an authorized class of terminals to emit from the current list randomly selected from the current list, by updating the list of classes authorized to transmit and by notifying r the return channel to the terminals the updated list of classes authorized to transmit; and when the crossing of the second lower threshold SL causes a decision to decrease the capacity of the channel, the gateway triggers (424) a decrease in the level of flow control by authorizing the transmission to a class of terminals forbidden to transmit from the list current suite, randomly selected from the current list, updating the list of classes authorized to transmit and notifying back to the terminals the updated list of classes that are allowed to transmit.
[13" id="c-fr-0013]
A system for transmitting data packets or packet fragments, comprising a plurality of user terminals (4, 6, 8) and a connection gateway (12) GW to a second network, each terminal (4, 6, 8). ) being configured to transmit data packets or packet fragments to the uplink gateway (12) GW on an uplink (24), switched between a first contention access mode using an RACH split contention channel shared by the plurality of terminals and a second DAMA on-demand reservation access mode using a reserved channel on request DAMA; the transmission system being characterized in that each terminal (4, 6, 8) is configured to receive almost in real time from the gateway via a return channel or information representative of the current transmission resources allocated to the contention channel RACH and DAMA On Demand Reservation Access Mode; each terminal (4, 6, 8) is configured to direct data packets or packet fragments over the contention channel RACH via a contention access or a reserved channel on demand via access to the DAMA request according to the the size of the packets and their class of service, and information representative of the current transmission resources allocated to the RACH contention channel and the DAMA request reservation access mode, The information representative of the current allocated transmission resources being provided and transmitted at the terminals of the plurality on a return channel.
[14" id="c-fr-0014]
A data packet or packet fragment transmission system according to claim 13, wherein the GW gateway (12) is configured to implement the steps of continuously estimating on a width observation window. predefined and from reception measurements in said expected burst observation window a first measured probability of reception of an empty expected burst Pe, or a pair of measured probabilities formed by the first measured probability Pe and a second measured probability of successful reception of a burst Ps, or a third measured probability of a salvo having suffered a Pc collision; determining a current magnitude Gr monotonically responsive to the external load of the contention channel RACH from the first estimated probability Pe or the third probability Pc or from the pair of probabilities (Pe, Ps) and parameters defining the protocol access to restraint; then when a crossing of a first upper threshold SH by the current magnitude takes place once or more consecutive times away from the value of the magnitude corresponding to the nominal external load, increasing the current capacity of the transmission channel by releasing additional communication resources in terms of additional frequencies and informing on a return path the terminals of the new composition of the enhanced capacity transmission channel; and / or when a crossing of the second lower threshold S1 takes place by the current sensing magnitude once or more consecutive times away from the value of the magnitude corresponding to the nominal external load, decreasing the current capacity of the channel of transmission by withdrawing communication resources in terms of frequencies from the transmission resources currently available and by informing the return channels of the new composition of the reduced capacity transmission channel.
[15" id="c-fr-0015]
The data packet or packet fragment transmission system according to claim 14, wherein the connection gateway (12) and the terminals (4, 6, 8) are configured to implement a flow control mechanism. and a congestion control mechanism through the regular and frequent provision by the connection gateway of a current list of terminal classes authorized to transmit and terminal classes not authorized to transmit.
[16" id="c-fr-0016]
16. An uplink transmission terminal of data packets or fragments of packets of data packets or fragments of packets, switched between a first contention access mode using a contention channel RACH and a second access mode to reservation on request DAMA using a channel reserved on request DAMA, the terminal (202) being characterized in that it comprises: a first access (204) with contention RA and a second access (206) to the request DAMA respectively comprising a first RA queue (230) connected to a first RA access output terminal (232) and a second DAMA queue (234) connected to a second DAMA output terminal (236); and .- a first uniform set (208) of queues connected exclusively to the second demand access (206); and a second (218) mixed set of queues connectable separately and selectively over time to one of the two accesses from the first contention access RA (204) and the second access to the request (206). DAMA; and a packet classification and first referral unit (228) configured to classify packets according to their size and service class in terms of quality of service (QoS), and to route packets based on this classification. either towards the first uniform set of queues, or towards the second mixed set of queues.
[17" id="c-fr-0017]
A transmission terminal according to claim 16, further comprising a processing and convergence unit (242) connected upstream to an input terminal (248) of the packets at the first and second sets (208, 218) of signal queues. waiting and upstream at the first and second ports (204, 208), and a resource management agent (244) of the RA and DAMA ports connected between a signaling signal receiving return port and the processing unit The access resource management agent (244) is configured to: * monitor information representative of the current transmission resources available on the RACH contention channel and the access mode to the DAMA request, and. * initiating resource requests based on the filling of the queues of the first and second sets; The processing and convergence module is configured to: * fragment the packets, outputted from the queues of the second mixed set, into one or more packet fragments according to the size of the packets, and then. packets or fragments of packets according to the respective priorities associated with the packets and determined by the quality of service classes of said packets, then. * pre-allocating the packets or fragments of packets through pre-assignment information access mode mode, on an access mode, taken from the first RA access and the second DAMA access, based on information representative of the current transmission resources allocated to RA and DAMA accesses and of a predetermined type of convergence , taken from partial convergence and total convergence, then. * encapsulate packets or packet fragments according to an encapsulation protocol that depends on type of convergence, then. * direct packets or fragments of packets to one of the two accesses taken from the RA contention access and access to the DAMA request according to the pre-assigned access mode.
[18" id="c-fr-0018]
18. Computer program comprising instructions for implementing the transmission method defined according to any one of claims 1 to 13, when the program is executed by one or more processors of a transmission system defined according to the one of claims 13 to 15.

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FR2925808A1|2009-06-26|COMMUNICATION METHOD IN A NETWORK COMPRISING A PRIMARY NETWORK AND A SECONDARY NETWORK

---

EP2608466B1|2017-02-01|System and method for an optimised retransmission of a message in a satellite communication

---

AU2766300A|2000-10-19|Method for improved transmission efficiency between data networks and wireless communications systems

---

FR3042081A1|2017-04-07|"METHOD FOR CONTROLLING A PACKET DATA COMMUNICATION SYSTEM AND COMMUNICATION SYSTEM IMPLEMENTING THE METHOD"

---

EP1172948B1|2011-10-05|Resource administrator device for a satellite telecommunication system

---

EP3637845A1|2020-04-15|Communication method

---

EP3151627B1|2017-12-20|Method for dynamically adapting the capacity of a contention-based transmission channel

---

FR2991531A1|2013-12-06|SHIELDING FRAME OF SHORT DURATION IN PHYSICAL LAYER

---

Cruickshank et al.2009|Bsm integrated pep with cross-layer improvements

---

EP3563494B1|2021-08-18|Method and device for reallocating satellite resources

---

WO2019077247A1|2019-04-25|Method of exchanging data frames, and wi-fi stations associated therewith

---

EP2645647A1|2013-10-02|Method for optimising the downstream rate of an asymmetric subscriber line, corresponding device, computer program product and storage medium

---

EP2476225B1|2014-02-26|Method and system for controlling the routing of a data stream from a class of service through a meshed and encrypted network

---

Wu et al.2004|Dynamic congestion control for satellite networks employing TCP performance enhancement proxies

同族专利:

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公开号 | 公开日

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US20170099675A1|2017-04-06|

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FR3042087B1|2017-12-01|

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CA2943498A1|2017-04-02|

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EP3151623A1|2017-04-05|

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EP3151623B1|2018-05-16|

引用文献:

---

公开号 | 申请日 | 公开日 | 申请人 | 专利标题

---

EP1686746A1|2005-01-31|2006-08-02|Agence Spatiale Europeenne|Packet datatransmssion over a shared transmission channel|

---

FR3004306B1|2013-04-05|2015-03-27|Thales Sa|A CONGESTION CONTROL METHOD FOR A CONTENT ACCESS NETWORK|US9871610B2|2015-10-30|2018-01-16|Citrix Systems, Inc.|Method for packet scheduling using multiple packet schedulers|

---

WO2017101011A1|2015-12-15|2017-06-22|华为技术有限公司|Configuration method and apparatus for scheduling resources, user equipment and enodeb|

---

CN108184214A|2016-12-08|2018-06-19|中兴通讯股份有限公司|A kind of method and device of determining data sender's formula|

---

US10645029B1|2017-03-20|2020-05-05|Barefoot Networks, Inc.|Fast reconfiguration of the data plane of a hardware forwarding element|

---

US10467261B1|2017-04-27|2019-11-05|Intuit Inc.|Methods, systems, and computer program product for implementing real-time classification and recommendations|

---

US10528329B1|2017-04-27|2020-01-07|Intuit Inc.|Methods, systems, and computer program product for automatic generation of software application code|

---

US10705796B1|2017-04-27|2020-07-07|Intuit Inc.|Methods, systems, and computer program product for implementing real-time or near real-time classification of digital data|

---

US10467122B1|2017-04-27|2019-11-05|Intuit Inc.|Methods, systems, and computer program product for capturing and classification of real-time data and performing post-classification tasks|

---

US10614224B2|2017-05-15|2020-04-07|International Business Machines Corporation|Identifying computer program security access control violations using static analysis|

---

WO2018217512A1|2017-05-24|2018-11-29|Motorola Mobility Llc|Performing an action based on a number of transmissions reaching a threshold|

---

US10499432B1|2018-05-08|2019-12-03|T-Mobile Usa, Inc.|Interactive spectrum management tool|

---

US10499252B1|2018-11-19|2019-12-03|T-Mobile Usa, Inc.|Dynamic spectrum sharing|

---

CN110365541B|2019-07-31|2021-06-15|腾讯科技（深圳）有限公司|Method for generating corresponding relation in gateway, and method and device for sending instruction|

---

CN111372213B|2020-02-24|2021-08-31|云南大学|Two-layer system of random multiple access and polling multiple access protocol based on FPGA|

法律状态:
2016-09-28| PLFP| Fee payment|Year of fee payment: 2 |

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2017-04-07| PLSC| Publication of the preliminary search report|Effective date: 20170407 |

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2017-09-29| PLFP| Fee payment|Year of fee payment: 3 |

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2018-09-28| PLFP| Fee payment|Year of fee payment: 4 |

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2020-10-16| ST| Notification of lapse|Effective date: 20200910 |

优先权:

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申请号 | 申请日 | 专利标题

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FR1502051A|FR3042087B1|2015-10-02|2015-10-02|METHOD FOR TRANSMITTING SWITCHED DATA PACKETS BETWEEN A CONTENTION CHANNELAND A RESERVE CHANNEL ON DEMAND |FR1502051A| FR3042087B1|2015-10-02|2015-10-02|METHOD FOR TRANSMITTING SWITCHED DATA PACKETS BETWEEN A CONTENTION CHANNELAND A RESERVE CHANNEL ON DEMAND |

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EP16189786.3A| EP3151623B1|2015-10-02|2016-09-20|Method for transmitting switched data packets between a contention-based channeland a demand assigned channel |

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US15/270,999| US20170099675A1|2015-10-02|2016-09-20|Method for transmitting data packets switched between a random access channeland a demand assigned multiple accesschannel|

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CA2943498A| CA2943498A1|2015-10-02|2016-09-28|Method for transmitting data packets switched between a random access channeland a demand assigned multiple accesschannel|