MXPA01011464A - Apparatus and method for efficient tdma bandwidth allocation for tcp ip satellite based networks. - Google Patents

Abstract

A communication system balances message traffic between return channel groups and within the groups, so that the user does not control the specific transmission frequency used. Uplink frequencies and bandwidths for the return channels are set by the system in a return channel control message in the broadcast signal so as to account for system and return channel group laoding, and to account for user message backlogs. An initial transmission from a remote user may be made using an ALOHA type burst signal that provides a message backlog to the control station, and is made on a frequency determined from a randomly weighted, load based frequency selection process. The system, and not the individual users determine the frequency and channel allocations. For large backlogs or priority users, periodic bandwidth is provided. A method for balancing loads among and between groups of return channels in the communication system includes requesting return channel bandwidth in an uplink message from a remote user to a control station. The uplink message may include both a backlog indicator and a bandwidth allocation request provided to a Network Operations Center (NOC) which can be used to set the return channel bandwidth and frequency for the remote uplink. A user message is transmitted on the designated return channel frequency using bandwidth allocated in accordance with the backlog indicator and a bandwidth allocation request so that traffic loads are maintained in balance between established return channel frequency groups, and within each return channel frequency group.

Description

'APPARATUS AND METHOD FOR THE EFFICIENT DISTRIBUTION OF TDMA BANDWIDTH FOR NETWORKS BASED' TCP / IP SATELLITE '< FIELD OF THE INVENTION This invention relates generally to a distribution scheme of bandwidth for Time Division Multiple Access (TDMA) systems, and specifically to an efficient distribution of bandwidth for control protocol systems of Transmi s ion / Internet Protocol (TCP / IP) in a satellite network based on TDMA.

"I * sji- 15 BACKGROUND OF THE INVENTION The use of satellites for Internet and Intranet traffic, in particular the digital video signaling by the use of Digital Video Transmission (DVB) and 20 bidirectional broadband communication. It has recently received a lot of attention, satellites can help alleviate Internet congestion and bring the Internet and interactive applications to countries that do not have an existing network structure, as well as provide interactive broadband application support. a means to utilize satellite technology in this developing field, very small aperture terminals (VSATs) provide fast and reliable satellite-based telecommunications among an essentially unlimited number of geographically dispersed sites VSAT technology has established effective tools for work on the internet via LANs, transfer of images ult media, interactive and interval data transmission, interactive voice, transmission data, mute data, and? ,% - s video communications. Internet Protocol (IP) is the most commonly used mechanism for transporting data from multiple sources. Examples of satellite networks capable of transporting IP data include the VSAT system of the Personal Earth Station (PES) of the Hugues Network System and the DirecPC® system of the Hugues Network System. Combining VSAT transmission with standards-based IP multilanguage ensures Y? to users a less expensive and more flexible approach to achieve a high-quality real-time transmission. Satellite Digital Video Transmission (DVB) and Internet Protocol (IP) technology have converged ("IP / DVB") to allow users transparent access to a variety of bandwidth content, including video in I live, large software applications, and web sites with a lot of media content. In support of these developments, VSAT systems, such as the aforementioned Personal Terrestrial Station, allow commercial users to access one of a generally limited number of satellite back channels to support bidirectional communication. The return or arrival channel selection is generally restricted to only a group of only a few of the possible channels preconfigured by a combination of hardware and / or software limitations. Some commercial systems may use a VSAT system terminal for Internet access in order to receive HTTP responses through the satellite transmission channel radio frequency (RF) channel without interference-when distributing unique time slots to each user on each channel . Access is controlled using a frame-based approach, and precise system synchronization is necessary to allow multiple users to access the bandwidth (ie, time-slot access) necessary to transmit the information in a multiplexed manner. the return channel. The transmissions are grouped into frames, with a sync signal ("sync") generally provided at the beginning of each frame. Following the synchronization of the frame, there is a certain number of "fractions" of time within the frame for transmissions-in burst. In the simplest case, a fraction of time that represents a fixed amount of bandwidth is distributed to each of the users who need to transmit information. Each TDMA user \ gets a specific time interval (or intervals) on the channel, and that the time interval for the user is set during transmission. In more complicated systems, the multiple time fractions become available to users based on the need for transmission or in a hierarchy scheme After all the time fractions have elapsed, another signal is transmitted. However, even if the user has nothing to transmit, the time frame is still reserved, resulting in an inefficient use of the available bandwidth.The TDMA requires a method to synchronize the times of burst transmission to reduce burst overlap and the consequent "collisions" of transmissions of different users, in addition, to provide each remote user with access to the uplink bandwidth required (essentially equivalent to interval access). ) becomes more difficult when you "share a larger number of incoming or uplink channels" re a large number of users. With the TDMA, each VSAT accesses a control node through the satellite by sending bursts of digital information on its assigned radiofrequency carrier. Each VSAT sends bursts in its allotted time with relationship to the other VSATs in the network. Splitting access in this way - by time intervals - allows VSATs to make the most efficient use of the available satellite bandwidth. As with most TDM-based protocols, the bandwidth is available to the VSAT in fixed increments whether necessary or not, as described above. It is difficult to establish an equitable distribution of uplink bandwidth for each of the incoming or uplink users due to the non-uniform load (ie, that •• fluctuates between heavy or light) within a group of uplink channels. uplink, and due to the relatively non-uniform load between groups of uplink channels. Figure 1 provides an exemplary conventional satellite communications system * 100 which limits each of the possible "k" remote users 140 to a group of return channel 160 from among "n" available groups. Each of the n back channel groups 160 the consumer market, the industry has been dedicated in addition to the internet work of < ? multiple satellite transmission networks and their associated uplink or incoming ("inbound") channels. Customized > * that the market expands, the number of possible uplink users also increases, and the above approaches for the distribution of channel bandwidth back to users in predetermined, fixed uplink channel groups necessarily requires hardware and additional system complexity to accommodate increasing uplink demand. If the return channel groups base their frame synchronization on a particular satellite transmission which is not common to all remote users in the return channel groups, then it is necessarily limited to the users to their preassigned channel back group. , thus limiting flexibility. In addition, this approach becomes progressively inefficient both in terms of hardware distribution, cost, and uplink bandwidth utilization, because many of the available groups of upstream channels can be heavily or lightly loaded or subjected to a load imbalance in relation to other incoming groups. This could be the result that each user must be configured in an * non-flexible way to access a specific incoming channel, or only a limited number of channels, due to hardware or software limitations, or synchronization considerations. plot previously described. This problem is exacerbated by the burst-like nature and somewhat unpredictable nature of such transmissions, which can result in inefficient use of the available bandwidth. Various solutions for the distribution of bandwidth are available for "casual use", or non-critical uplink systems, and can '%. used in satellite communications 100 - * $ ' conventional ones shown in Figure 1. For example, known ALOHA techniques are used to minimize the overhead associated with bandwidth distribution to users where data is not transmitted. ALOHA was developed to coordinate and arbitrate access to a shared communications channel. Although originally applied in terrestrial radio broadcasting, the system has been successfully implemented in satellite communications systems. An average access method, such as ALOHA, aims to prevent two or more systems from transmitting at the same time in a shared medium. There must be some method to handle the so-called "collisions". In the ALOHA system, a system transmits at any time that the data are available. If another system transmits at the same time, a collision occurs, and the frames that were transmitted are lost. However, a system can listen to transmissions in the middle, including its own, or wait for a recognition from the destination station to determine if the frames were currently transmitted. However, the so-called pure ALOHA has a bandwidth efficiency of approximately seven percent, meaning that it must be distributed approximately 14 times However, the usu fraction of the second time interval before they can transmit. Also, data may be lost if users contend for the same interval, but not as much data as would be lost in pure ALOHA would be lost. However, tests have shown that interval ALOHA has a performance advantage, and that it is more suitable for short, "burst-type" messages in applications that require fast response times, such as a card verification process. point of sale credit and ATM transaction. This containment technique allows VSATs to transmit at any time, and continue transmitting if they receive recognition that no other station is sending. However, this method requires that the channel utilization be maintained at approximately 18 to 36 percent. Other systems use an interval reservation access mode, in which the guest reserves intervals for each user to transmit an assigned number of packets. When allocating allocated message bandwidth, use of random access ban width, consequently improving process and transfer performance. A disadvantage of this method is that more time is required for channel configuration, adding an additional delay, and there may be too few or too many packets allocated for the 10 transmission of the message for each user, leading to at least some inefficiency in the use of bandwidth. In addition, the dynamic redistribution of bandwidth is not carried out efficiently using this approach. Even if a channel access scheme of the ALOHA type is successfully used to acquire access to the bandwidth for the uplink, there is still the problem of over or underloading the back channels, and also of having an imbalance between the channels. channel groups of vue 1 ta. Therefore, what is needed is an apparatus and method for dynamically allocating the uplink bandwidth depending on the of user demands for return channel access. What is also needed is an apparatus and method for balancing the uplink loads between the return channels that share a common uplink channel pool, and this also balances the load between the groups of uplink channels. that share the common frame synchronization. \ BRIEF DESCRIPTION OF THE INVENTION The present invention solves the aforementioned problems to provide a system, apparatus, and method for allocating uplink bandwidth depending on the user's demand for the * »? return channel access, and to ensure that a balanced load condition is maintained between the return channel groups. and - In one aspect of the invention, a control station for bidirectional satellite communications includes an RF section for transmitting a transmission signal and receiving a return channel from a remote user. A channel subsystem temporarily outgoing user message «Il until it is transmitted. A transmitter uplinks the outgoing user for a period assigned after the initial transmission frame time using an assigned transmission frequency determined by a group status message received in the transmitted signal. If necessary to achieve a load balance, the transmission frequency can be changed to a different transmission frequency within a current channel group, or changed to a frequency within a different channel group, depending on the relative load of the channel. the two groups of return channel, and the requirement of remote user bandwidth, as reported in the status message. of group received from the transmitted signal. The ability to assign the transmission to another frequency in a group of back channel * - * •! different is result, at least in part, to share a common system frame synchronization between all the channel back groups. In a third aspect of the invention, a method for controlling a return channel from a control station includes transmitting a transmission signal, receiving a reverse channel uplink from a remote user, and establishing a bandwidth and return channel frequency with a return channel controller which provides a distribution message on the transmission signal to be received by the remote users. The bandwidth and frequency of the return channel are established by evaluating an accumulation indicator provided by the remote user, and by evaluating the relative loads of all the return channel groups and individual transmission frequencies within the channel groups back. In a fourth aspect of the invention, a method for transmitting a frame synchronized message from a remote user includes receiving a control node synchronization message in a signal * 20 transmitting, determining an initial time frame of the return channel using the control node synchronization message, temporarily storing an outgoing user message, and transmitting the user message * 25 outgoing on a transmission frequency »E during an assigned period after the initial time of the return channel frame. The i transmission frequency and the assigned bandwidth can be determined by an incoming assignment message received in the transmission signal. The remote user can transmit micially on a back channel configured to support a burst signal of the ALOHA type. This burst signal includes an indication of the message traffic accumulation of the remote user to the control node. The remote user can then move to a return channel which shares access with another remote user, or which provides dedicated uplink access, depending on the available resources of the system and the requirement of the remote user's bandwidth. The initial ALOHA-burst uplink is sent on a transmission frequency selected locally by the remote user using a randomly weighted frequency selection process based on the load of the system or group reported by the transmission signal. In a fifth aspect of the invention, a communication system for balancing the traffic on a plurality of return channels - "α-" includes a control station for transmitting 77., a transmission signal to a remote user.

The transmission signal includes a real-time frame marker, a synchronization message, and a return channel control message. A receiver at the remote user receives the transmission signal and determines an initial channel frame time back v using the non real time frame marker and the synchronization message. A transmitter on the remote user uplinkes a user message on one of the return channels for a predetermined period after the initial time of the return channel frame. An uplink frequency and bandwidth of the return channel are determined by the control message of the return channel in order to give a reason for the § loading of the system and the channel group of: return, and to account for the accumulations of user messages. An initial transmission from the remote user can be made using a burst signal of the ALOHA type which provides an indication of < accumulation of messages. This transmission < Initialization can be made at a given frequency from a load-based frequency selection process in order to and ensure the dynamic balance between the return channel groups. In a sixth aspect of the invention, a method for balancing the loads between the groups of return channels in a communication system includes requesting the bandwidth of the return channel in an uplink message from a remote user to a station. of control. The uplink message may include an accumulation indicator and a bandwidth distribution request. A bandwidth of the back channel can be distributed to the remote user when processing the accumulation indicator and a channel distribution message is provided from the control station to the remote user in the transmission signal. The channel distribution message can also distribute the bandwidth of the return channel. Is a user message transmitted on a channel? return according to the channel distribution message. The present invention in all its modalities, collectively and individually, has a certain number of characteristics that distinguish it from conventional bandwidth distribution schemes. For example, the present invention allocates bandwidth dynamically based on how much users require, and directs the changes of the uplink frequency to balance the traffic load. The approach of the apparatus, system and method of the present invention not only balances the load between the return channel groups, but also within each group of return channel, ensuring an optimized bandwidth distribution scheme. The system is configured to automatically balance the load each time a remote user starts a new uplink session, and carries out the goal of having just the same number of uplink users who share each incoming channel, even with a number large and progressive system users. This approach is particularly for TCP / IP satellite traffic, and is a highly desirable component for operating an efficient TCP / IP system by a TDMA-based satellite system, which includes multiple satellites working in a network with the Support ground infrastructure required. Finally, the method and system of the present invention allow the expansion to an essentially unlimited number of users on the same return channels without excessive hardware and software modifications, and allows all users to have access approximately equal to capacity, or bandwidth, of the 7 channel back. This capability originates, at least in part, by sharing the system frame synchronization between all the return channel groups, regardless of the transmission source of the return channel control information sent from the control station, which possibly includes such mute tisatelí links. The system preferably shares a common non-real time reference provided to all remote users, regardless of whether they are recited and the advantages of the more easily apparent from the detailed description given below. However, it should be understood that the detailed description and specific examples, while indicating a preferred embodiment of the invention, are determined only by way of illustration, since various changes and modifications within the spirit and scope will become apparent. of the invention by this detailed description for those skilled in the art.

BRIEF DESCRIPTION OF THE INVENTION The features and advantages of the invention will be more easily understood after consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings in which: Figure 1 represents a satellite communication system; Figure 2 shows the bidirectional satellite communications system 200 for accessing any of the groups of return channel 15, 260, and the limitation of the conventional transceiver 150 of only the "m" channels available in its assigned channel return group. Figure 2 also illustrates two NOCs 210, ie NOCÍ 210a and NOC2 210b, which each provide at least one DVB Transport Stream 220 (eg, 220a and 220b) to satellite 230 for additional X retransmission. The DVB 25 transport stream retransmitted from satellite 230 is shown 2 only as the transport stream of DVB 220 for clarity. Each NOC 210 in the system of the present invention can provide support for various reception channels or projections. The symbol synchronization reference of the system 270 preferably provides symbol synchronization common to each NOC 210 in the system, so that the synchronization information used to derive the uplink frame start times can be recovered by all the remote users 240. The NOC 210 preferably also provides access to the internet or an intranet through a network access 170. However, the application of the method and system of the present invention is not intended as & limited to a system that has a specific number of NOCs 210 or remote users 240. In addition, the NOC 210 in Figure 2 is distinguished from NOC 110 in Figure 1 by each NOC 210 that has the ability to support traffic return channel of reception and processing from remote users 240 that is transmitted according to a common system synchronization scheme.

Multiprotocol (MPE). A preferred superframe message 300 is shown in Figure 3, in which a superframe marker is periodically transmitted. However, the superframe marker can be transmitted only every integral number of frames, such as every eight frames, for example. The stream preferably has MPEG-2 format adaptable to DVB which supports multiple MPE messages in a single MPEG frame. The transport stream may include MPEG 204 packets of fixed size, which may contain 188 bytes of user traffic and 16 bytes of error correction data in advance (FEC), for example. Preferably, an MPE header may also include specific media access control (MAC) data fields to indicate the type of media or traffic contained in the data stream, for example, the superframe numbering packet (SFNP), unidifusion, mui tdii ion, conditional access, i- 'back channel messages, or back channel group messages, and other data fields to indicate, for example, if the packet is encrypted. Correction can also be supported * £ * »! , »», E. Error in advance (FEC) at various rates, * * for example, the FEC rates of 1/2, 2/3, 3/4, 5/6, or 7/8. Also, the header of each plot '? J- can also contain a packet identifier (PID) to distinguish between the elementary flows in the transport stream of DVB 220 so that the remote user 240 can filter the message by the PID. For ease of description, the transport stream of DVB 220? V * 10 will hereinafter be referred to simply as "transmission". As regards the thrust of the present invention, the distribution of bandwidth and frequencies to the return channels as well as the functions of system monitoring and control can be carried out by means of the use of a series of messages. : contents in various bytes of the transmission stream transmitted to remote users 20 2 4 0. For example, the DVB MPE protocol layer is preferably provided for the MAC fields which support various MAC addresses as described above. In particular, the messages of MPEG-2, digital audio and files. The transceiver 250 provides a high speed, air return channel as an alternative to Y - and a low speed terrestrial return channel. The transceiver 250 contains the receiver (RCVR) 410, the processor 420, the RF transmitter (RF XMTR) 430, the synchronization recovery section 440, and the Transmission Unit. "(TU) 450. RF XMTR 430 modulates and transmits, preferably in burst mode, the arrival carrier to satellite 230 and NOC 210. RF XMTR 430 can operate with, and be controlled by, the TU 450 and the RCVR. 410 by the processor 420, "which can also govern the RCVR 410 15 by using, for example, a universal serial bus (USB) adapter (not shown). The y 'configuration parameters and arrival data from the processor 420 can be input to the RF XMTR 430 through a serial port 20 (not shown), and the transmitter status information from the RF XMTR 430 can also be provided to through the serial port to the processor 420. The TU 450 conditions the output data signal by incorporating the 25 signal protocols and the modulation scheme - > * 4 - . 4 - appropriate, for example the IP / DVB protocol and the TDMA using QPSK techniques, which include Displacement QPSK (OQPSK). The RCVR 410 receives transmission 220 • »5 from satellite 230 through the * X antenna section 460, and retrieves and provides appropriate signals related to synchronization to the synchronization recovery section 440. The synchronization recovery section 440 corrects or compensates for the reception time of the received frame marker according to synchronization information \ 7 contained in the received transmission signal, for example, in an SFNP. The section of Synchronization recovery 440 further enables RF XMTR 430 through processor 420 and TU 450 to transmit at the appropriate time according to a TDMA time slot distribution scheme. '~ Finally, the antenna (ANT) 460 propagates and receives the signals to / from the satellite 230. A description of the nature, approach and operation of the bandwidth and frequency distribution of the system and method of the present is given below. invention. The '-. Figure 5 shows the NOC 210. The (RCS) 510 in the N section of the sync processor section of the NO RCS 510 reen users re-turn and a re shown) in post-frame processing in transmission time to used finalm 'link Ascending derives from a channel pulse from the controller of c also the anc with frame figuration to the desm (BCD) 530. The n the RCS 510 is arranged to redundant for at least 28 return channels.

XY 1 Multiple sets of back channel subsystems 510 can be provided in a network array working (not shown) at each NOC 210 to allow processing of a large number of back channels, preferably up to 100,000 or more, per example. The return channel traffic from the remote users provided by the RF section of the NOC (not shown) and the incoming receiver of the NOC (not shown) and routed through the signal distribution section 540 of the NOC applies to one or more BCD 530 to demodulate the return channel data received from the remote users, as directed by the return channel controller 520. In addition, the return channel controller 520 provides frame pulses to the synchronization section 550 of the NOC. The synchronization section 550 of the NOC preferably includes the appropriate means (not shown) for measuring and comparing packet delays associated with both internal NOC delays and satellite delays of the NOC, respectively. The synchronization section? . uplink which is synchronized j preferably through the bidirectional satellite communication system 200. The equipment, signals and subsystems within each NOC 210 and transceiver 250 are preferably interconnected through one or more local area networks (LAN) 1 (not shown) and, even more preferably, f are interconnected according to an open system architecture approach which allows modifications and updates to be carried out more easily as improvements as they become available or desirable to improve in the software and hardware. The fundamental synchronization approach of the present invention which allows the distribution of bandwidth and frequency in a large number of return channels to be carried out in different groups of return channel is to provide information to the RCVR 410 so that the transceiver 250 YY can accurately synchronize its burst transmission time as a displacement of ... the superframe header received. The superframe header received in a superframe numbering packet (SFNP) transmitted in the transmission is used by each remote user 240 to synchronize its start of > transmission of the frame marker to the pulse of 5 superframe marker generated by the return channel controller 520. This superframe numbering packet (SFNP) is? used to ensure network synchronization J t for the return channels, and as a beacon to identify which network is connected. This packet is transmitted by the MAC address of "Superframe Numbering Package" (see Table 1). However, the reception of the SFNP is not sufficient by itself because there are 15 delays arising from the time that the return channel controller 520 generates the superframe header until the time receiver 410 currently receives the SFNP. The additional correction is applied by the receiver 410 to account for the outgoing delay of the internal NOC, a delay of the satellite transmission time of the NOC, and a delay of transmission from the satellite to each of the specific remote users 240, 25 preferably based on the parameters ? - »í- * 550 of the NOC, and therefore l # is also transmitted in a subsequent SFNP message to the remote users 240. Knowing the initial synchronized uplink frame time 5, and preferably sharing the same time initial uplink frame between all remote users 240, allows the NOC 210 to efficiently control the distribution of the 10 bandwidth and the frequency assignments among all remote users 240, both between and in the return channel groups 260 The operation of the communications synchronization system of the present invention will now be described. The NOC 210 takes formatted data packets and transmits them to the transport stream of DVB 220 to the satellite 230 for further retransmission to the remote users 240. The data stream or information of * < " 20"Useful load" is transmitted following a header and vector of micialization of properly formatted MPEs, if the packets are encrypted. Included in the DVB 220 transport stream is the SFNP which provides a superframe marker, as well as the i-t-r -i ret arr sup ant SFN sup sec 240 enl tra rec te re tra ct to the rec rec des raz with ini axis 410 finds out about the available A turn channel groups upon receiving the * s¿ | IGDP messages (see Table 2). The X 3 > 'f 240 remote user will use only one return channel if your TU 450 and RF XMTR 430 are available. 3) Range Determination: If the remote user 240 has not configured his synchronization from his current position 10, he will request a range determination session from the NOC 210 when sending a range determination request through a determination burst. rank. A closed-loop process is used to fine-tune timing and power. 4) Request bandwidth: Once the range of the site has been determined and the data is about to be transmitted, a burst of ALOHA is used to transmit the data. An accumulation indicator will be used to activate the NOC 210 in order to distribute the bandwidth. 4 Send Traffic The remote user 240 sends the user traffic through a return channel 3. -J distributed in one of the groups of 5 return channel 260 using the bandwidth of "flow" distributed, that is, the bandwidth that essentially devotes the entire transmission frame of TDMA to the remote user. 10 240. The IGDP package (see Table 2) is preferably used to define the channels < "- back in a group of return channel 260 and its availability, and to allow the selection 15 of the groups of return channel for the user traffic (using ALOHA for the", configuration) and determination of rank. The "- -". Back channel groups can also be used to allow the sharing of the load i 20 between a number of return channels, and to minimize the outgoing bandwidth of the NOC 210 required to control the bandwidth distribution of the return channel. The return channel groups preferably limit the amount of information that needs to be placed in the associated memory or processed by the receiver 410. The IGDP is preferably sent by the MAC address of the transmission of the return channel. The IGDP preferably uses one packet per channel group back by super frame, for example, 26 kbps bandwidth per 75 return channels per group, and 300 return channels. It can also be transmitted 10 for a multi-address address "Completely RCVR". Each receiver 410 preferably monitors all the IGDPs. The receiver 410 preferably filters the channel types of 15 turns that we are configured to support, and can delay the definition if it is not received by three superframe times. An incoming group table is preferably created in each receiver 410 from the information 20 contained in all those packages. This table is preferably quasi static in order to minimize the overhead processing in processor 420 required to reorganize its incoming pool table. Minimizing 25 table changes is desirable to reduce the potential interruptions to system operations 200. When the remote user 250 is active, i.e. has bandwidth, preferably he monitors his currently assigned incoming group, as well as a second incoming group near the time that moves between the incoming groups. In order to limit the latency when one of the remote users 240 needs to transmit, all inactive transceivers 250 with valid range determination information can make a randomly weighted selection, eg, every 4th branch time (in the superframe), among all incoming groups that notice an ALOHA Metric other than zero. The remote user & *? 240 will preferably start to wait until the incoming group, and the previous incoming group will preferably also monitor until all the BAPs have been received, or lost. previous By making such a weighted selection, randomization, the possibility of suddenly making a slightly loaded uplink channel is reduced if multiple remote users 240 require link access between the receivable and the 5 referenced 5 grup sali prop reco sopo 10 of l pend reco pref 15 deci for one asig tran 20 from prev reco anch 25 for : - per entry, 75 entries per group, and 300 entries, for example. Since it is preferably transmitted in the multicast address of the incoming group, each receiver 410 will only have to process 134 kbps. To try to ensure that active users do not have an impacted performance, or data lost by any load balancing in a return channel subsystem 510, it is desirable to observe the following rules by the remote user 240: 1) At least five frames above to move the remote user 240 to a different incoming group, but on the same * return channel subsystem 510, it must and * be notified to the remote user 240, so that it can start to buffer both incoming group flows, and will require continue the monitoring of the * i flows until all outstanding incoming acknowledgment packets (IAPs) are received or lost. See below Table 5 for a description of IAP. 2) There must be at least one frame time that does not have bandwidth distributed among the bursts that are assigned to the different inputs. This is to ensure that the remote user 240 will be able to * fill in all their assigned intervals, and that he will have at least one frame time to adjust to the new frequency. This requirement applies preferably for bursts that are defined in consecutive BAPs, and when they move between the incoming groups in the same RCS 510. There must preferably be at least one frame without bandwidth 15 distributed between the normal bursts and the bursts of rank. This is to ensure that the transceiver 250 will be able to fill all its assigned ranges, and that it will have 20 at least one frame time to adjust the transmission parameters. After the BAP that moves the remote user 240 to a different incoming group is sent, the RCS 510 25 will continue to receive bursts under the Old incoming group during a time in excess of the round trip delay. The RCS 510 preferentially accepts and recognizes these frames, and the remote user 240 must continue to recognize the acknowledgments derived from the old incoming group, the remote user 204 must not have its bandwidth moved to a different incoming group 10 while X it still finds a previous incoming group that it has moved recently Transceiver 250 will only be assigned multiple bursts during a single frame time if they are all in the same input, and are all reciprocally connected in the frame, but without the 20 burst overload on and Yi off the RF XMTR 430 for each packet, and all bursts, except the last one, k. preferably they are large enough for the size package maximum (largest multiple of the interval size <256, for example), but only the first will have an overburst / burst aperture included «* > % 5 in its size. 8) Once the ID of the Assignment (see Tables 3a-3d) to a transceiver 250 in an incoming group will not change while transceiver 10 remains active, except as part of the being moved between the incoming groups. 9) Once an Assignment ID is assigned to a transceiver 250 in an incoming group, it should preferably be left empty for five superframe time after it is no longer in use. The incoming acknowledgment packet 20 (IAP) in Table 5 is preferably used to explicitly recognize each incoming packet for the allocated bandwidth with a valid cyclic redundancy code (CRC), regardless of the presence of any encapsulation data 25, to allow a recovery > * -more rapid of incoming packet errors. The range determination packets are not 'k: -? Distributed and ALOHA are explicitly recognized • (see Table 5). The IAP preferably uses one packet per incoming group, P per frame, or approximately 57 bandwidth for 25 Active Users per entry, 75 entries per group, and 300 entries, for example. Because the IAP is preferably transmitted in the multipath direction of the incoming group, each receiver 410 will only have to process approximately 15 . If the IAP is lost f, the transceiver 250 can automatically retransmit the packet. Could the loss of the IAP for a particular input group be detected by the following IAP packet? 7 received, or if the IAP is not received during four times, for example. As for the transmission of back channel messages, the burst data frame has structures specific to the ALOHA bursts (i.e., undistributed bandwidth), and when the bandwidth is distributed. Examples of the different types of packet headers preferably used for these two data frame structures are provided in Tables 6 and 7, respectively. Two different header structures can be used to maximize the efficiency of distributed bandwidth messages by minimizing the size of. the required message headers. The RCS 510 can detect the burst type from the frame numbering information in the packet header. The incoming packet format can consist of a variable size header and 0 or more bytes of encapsulated datagrams. The encapsulated datagrams are sent as a continuous stream of bytes of concatenated datagrams, preferably unrelated to the incoming packet. Proper interpretation requires reliable processing, in order, of all data bytes, preferably only once. To solve the problems due to the loss of data in the input, a sliding window protocol of selective recognition can be used. As is the case for such sliding window protocols, the sequence number space must be at least double the size of the window, and the data outside the window is dropped by the receiver. - < # > For distributed flows, that is, where the bandwidth has been distributed to a remote user 240 (see Table 7), the incoming burst data will preferably be retransmitted if it is not recognized in the IAP for that frame number, or if that recognition is lost. If synchronization problems occur, the RCS 510 can force the transceiver 250 to be inactive by eliminating the bandwidth distribution. This preferably causes the transceiver 250 to reset its sequence number and datagram counter to 0, and start at the beginning of a new datagram. Since the sequence number is preferably reset each time the transceiver 250 is set to active, any data sent in the undistributed range determination bursts or ALOHA can be doubled due to retransmissions, if the recognition is lost, and also because to the Aloha of diversity, previously described.

When the reciprocally connected bursts are distributed to the same transceiver 250, it preferably does not turn off the unit, and will use the saved overload associated with the burst processing to send extra "payload", or user message traffic. This will help to maintain a desired mapping of 1 to 1 of the bursts of distributed packets. In the system, the apparatus and method of the present invention, and with a preferred channel and back-channel addressing scheme, there are essentially no limitations on the number ("k") of remote users 240 that can uplink data in a return channel. Preferably a minimum of 224 (~ 16 million) transceivers are supported by the addressing scheme incorporated within the DVB stream, and, even more preferably, up to 228 (-256 million) transceivers are supported. In addition, because the return channel is preferably a substantially lossless channel, compression techniques can be efficiently employed to reduce the bandwidth requirements. The compression of ** __Í- IP header has the potential to deliver a tremendous improvement in bandwidth, since "? 4 such compression eliminates 10-15 bytes per IP packet." 5 Although a preferred modality has been previously described in terms of of a TDMA range or bandwidth distribution approach, this preferred embodiment is in no way considered to be limiting, and is provided only by way of example, as a further example, the method and system for providing bandwidth and frequency distributions. Frequency can be carried out in any type of communication system that has multiple users sharing the same means, and can find particular application in any time system at intervals requiring bit synchronization, eg, a frequency-time system that uses a phase locked circuit (PLL) or frequency blocking circuit (FLL) based on the same standard d and synchronization. In addition, although the present invention provides benefits for using TCP / IP applications, the system, apparatus and method of the present - = -invention is not limited to this, 'i * selection of protocols. It will be obvious that the present invention can be varied in many ways. Such variations should not be considered as a departure from the spirit and scope of the invention, and all such modifications as will be obvious to those skilled in the art are intended to be included within the scope of the following claims. Therefore, the breadth and scope of the present invention are limited by the scope of the appended claims and their equivalents.

Table 1 Superframe Numbering Package Format < '(SFNP) -Ss- 'Table 2 Incoming Group Definition Package Format (IGDP) t y #c 4 - 10 15 20 25 and I 3H Table 3a Recognition of Aloha * ¥ Table 3d - Command Change inbound group 10 fifteen twenty 25 Table 4 Bandwidth Distribution Package Format (BAP) 10 fifteen 20 «s, 4 25 useful ? r Table 4a - Burst Distribution Record Format -I -t and -A- Table 7 - Incoming Package Format t? »(Distributed) -« .fe you ,"*.

Claims (1)

1. * - 76-burst channel demodulator. The control station according to claim 2, characterized in that the return channel controller dedicates the burst channel demodulator to the remote user based on a request for distribution of bandwidth provided by the return channel information. The control station according to claim 1, characterized in that the return channel controller establishes the user bandwidth of the return channel when evaluating a user accumulation indicator provided by the remote user in a return channel message. . The control station according to claim 5, characterized in that the return channel message is a burst message of ALOHA. The control station according to claim 6, characterized in that the burst message of ALOHA contains a request for distribution of bandwidth. 8. The control station according to claim 7, characterized in that the f back channel handler assigns the remote user periodic bandwidth in response to the bandwidth distribution request. The control station according to claim 6, characterized in that the ALOHA burst message contains an information packet of a predetermined interval size. The control station according to claim 5, characterized in that the back channel controller distributes bandwidth if the user accumulation indicator is greater than a threshold value. The control station according to claim 1, characterized in that the return channel controller also assigns a frequency of the return channel. The control station according to claim 11, characterized in that the back channel controller allocates the frequency of the back channel through an incoming allocation packet provided to the remote user through the transmission signal. -. ?? M 13. The control station according to the indication 11, characterized in that the return channel controller changes the frequency of the return channel from the first frequency to a second frequency, the first and second frequencies being within a first group of return channel. and a second group of return channel, respectively. 14. The control station according to claim 1, characterized in that the return channel controller changes a ^ frequency of the return channel. 15. The control station according to the reign indication 14, characterized in that the return channel controller changes the frequency of the return channel from a first frequency to a second frequency, the first and second frequencies 20 being within the same group. of return channel. The control station according to claim 1, characterized in that the transmission signal is a DVB transport stream asynchronous. 25 1 7 The counting operation according to claim 1, characterized in that the return channel information is provided by a TDMA signal. ^ "- * - - - - 18. The control station according to claim 1, characterized in that the return channel controller distributes a return channel of flow access to the remote user based on a request for distribution of bandwidth. provided by the return channel information 19. The control station according to the indication 18, characterized in that the return channel controller distributes a dedicated frequency to the remote user 20. The control station according to claim 18, characterized in that the return channel controller changes an assigned frequency of the remote user 21. The control station according to the rei indication 1, characterized in that the return channel controller establishes the user bandwidth of the return channel by providing a Bandwidth distribution package to the remote user through the transmission signal. 22. The control station according to claim 1, characterized in that the return channel controller assigns the frequency of the return channel when evaluating a user accumulation indicator provided by the remote user in a return channel message. The control station according to claim 1, characterized in that the RF section receives a plurality of back channels from a plurality of remote users, and wherein the back channel subsystem processes the back channel information of the plurality of return channels and establishes the respective user bandwidths in each of the pluralities of return channels. 24. The control station according to claim 23, characterized in that a subset of the plurality of return channels is configured to support the ALOHA burst transmissions. 25. The control station according to claim 23, characterized in that the return channel subsystem also includes a * incoming group definition packet provided to the remote user through the transmission signal. 29. A transceiver for transmitting a synchronized frame message to a control node, characterized in that it comprises: a receiver which detects a control node synchronization message in a received transmission signal; a synchronization recovery section which uses the control node synchronization message to determine an initial transmission frame time; a message buffer for storing an outgoing user message; and a transmitter adapted to uplink the outgoing user message on a transmission frequency during a period assigned after the initial transmission frame time; the transmission frequency being determined by a first incoming group definition packet received in the transmission signal, in which the first incoming group definition packet is * and find associated with a first group of return channel. X 30. The transceiver according to claim 29, characterized in that it further comprises a processor which provides an indicator of accumulations of traffic included in the outgoing user message. 31. The transceiver according to claim 29, characterized in that the transmission frequency is in the first turn channel group 32. The transceiver according to claim 31, characterized in that the transmission frequency is changed to a different transmission frequency. in the first back channel group based on the first incoming group definition packet received in the transmission signal 33. The transceiver according to claim 31, characterized in that the receiver receives a second incoming group definition packet in the transmit signal and the transmission frequency is changed to a different transmission frequency in a second second channel group based on the second incoming group definition packet 34. The transceiver according to claim 33, characterized in that the 5 receiver monitors both the incoming group definition packets first and second in the signal of tr ansmission after the uplink bandwidth has been distributed by the control node. 35. The transceiver according to claim 33, characterized in that the transmission frequency is changed to a predetermined number of frames after the receiver receives the second packet of incoming group definition. 36. The transceiver according to claim 31, characterized in that the transmission frequency is changed to a different # * transmission frequency in a second group of back channel using a random weighting based on a channel group load factor of return. 37. The transceiver according to the re-indication 29, characterized in that the assigned period includes at least one TDMA interval after the initial time of the transmission frame. yey? f ° 38. The transceiver according to claim 37, characterized in that the allocated period is determined by a distribution packet of received bandwidth in the transmission signal. 39. The transceiver according to claim 37, characterized in that the bandwidth distribution packet distributes a flow bandwidth in which a total of TDMA slots in a message frame are dedicated to the outgoing user message. 40. The transceiver according to claim 29, characterized in that the assigned period is determined by a predetermined traffic load established by the control node. 41. The transceiver according to claim 29, characterized in that the received transmission signal is an asynchronous DVB transport stream. 7 42. The transceiver according to claim 29, characterized in that the return channel groups. 43. The transceiver according to claim 42, characterized in that the transmission frequency is assigned to be in the first group of return channel based on a group load factor received in the transmission signal. 44. The transceiver according to the rei indication 42, characterized in that the The transmission frequency is changed to be in a different back-channel group with 15 basis in a group load factor received in the transmission signal. 45. The transceiver according to claim 42, characterized in that the transmission frequency is changed to a group 20 different from the plurality of return channel groups based on a random weighting factor provided in the transmission signal. 46. The transceiver according to claim 29, characterized in that the the 7? ntra compression without losses. 48. The transceiver according to claim 29, characterized in that the outgoing user message is transmitted in a return channel without losses. 49. The transceiver according to the indication 29, characterized in that the outgoing user message is modulated by the transmission frequency using a QPSK modulation scheme 15. 50. The transceiver according to claim 49, characterized in that the QPSK modulation scheme is a Displacement scheme of QPSK (OQPSK). 51. The transceiver according to claim 29, characterized in that the outgoing user message is limited to a maximum bandwidth by the control node. 25 52. E l t ra n s c ep t o r s 7.; ~ Y and claim 29, characterized in that the outgoing user message is in the ALOHA burst format. 53. The transceiver according to claim 52, characterized in that the ALOHA burst transmits the outgoing ~ user message at least twice. 54. The transceiver according to claim 52, characterized in that the ALOHA burst is retransmitted a maximum number of times indicated by a message received in the transmission signal. 55. The transceiver according to claim 52, characterized in that the outgoing user message contains a request for distribution of bandwidth. 56. The transceiver according to claim 52, characterized in that the ALOHA burst is a burst of ALOHA of intervals aligned with the initial time of the transmission frame. 57. The transceiver according to claim 52, characterized in that the outgoing user message has a smaller size than a predetermined threshold value. *. « of threshold. 62. The method according to claim 60, characterized in that the back channel uplink is a burst message of the ALOHA type. 63. The method according to claim 62, characterized in that the ALOHA type burst message is an interval ALOHA message. 64. The method according to claim 58, characterized in that the transmission signal is an asynchronous DVB transport stream. 65. The method according to claim 58, characterized in that the uplink of the return channel is a TDMA signal. 66. The method according to claim 58, characterized in that the back channel controller controls an uplink frequency of the back channel through an allocation message provided to the remote user through the transmission signal. 67. The method according to claim 66, characterized in that the controller of the return channel changes the frequency of the uplink of the return channel from a first frequency to a second frequency, ?FOR" . the first and second frequencies being found within a first group of return channel. 68. The method according to claim 66, characterized in that the return channel controller changes the frequency of the uplink of the return channel from a first frequency to a second frequency, the first and second frequencies being within a first channel group. back and a second group of return channel, respectively. 69. The method according to claim 58, characterized in that the bandwidth of the return channel is established according to a request for distribution of received bandwidth in the uplink of the return channel. 70. The method according to claim 69, characterized in that the return channel controller allocates periodic bandwidth to the remote user. > 71. The method according to claim 70, characterized in that the return channel controller assigns a flow bandwidth to the remote user. 72. The method according to claim 71, characterized in that the return channel controller allocates a dedicated back-channel uplink frequency to the remote user. 73. The method according to claim 58, characterized in that it further comprises: receiving a plurality of back channel uplinks from a plurality of remote users; and establishing a bandwidth of the return channel for each of the pluralities of back channel uplinks with the back channel controller. 74. The method according to claim 73, characterized in that the back channel controller controls a frequency of each of the pluralities of the back channel uplinks through an allocation message. 75. The method according to claim 73, characterized in that it establishes a bandwidth of the return channel for each of the pluralities of upstream channel backlinks includes predetermining a load of , * and i return channel traffic. 76. The method according to claim t + ¡73, characterized in that a bandwidth of the back channel is established for a portion of the plurality of back channel uplinks using a predetermined back channel traffic load, and a bandwidth of the return channel for at least one of the pluralities of the return channel uplinks is established based on a request for distribution of transmitted bandwidth in at least one of the pluralities of the uplinks of the return channel. 77. The method according to the rei indication 73, characterized in that it establishes a frequency of the return channel for each of the pluralities of uplinks of channel-return is based on evaluating a traffic load for each of the pluralities of uplinks of the return channel. 78. The method according to claim 73, characterized in that a group load factor for each of the plurality of back channel groups is transmitted periodically in the transmission signal. 79. The method according to claim 78, characterized in that a frequency for each of the plurality of back channel uplinks is determined by a corresponding group load factor. 80. The method according to claim 78, characterized in that a bandwidth for each plurality of back channel uplinks is determined by a load factor of 'h. corresponding group. 4 »81. The method according to claim 73, characterized in that establishing a back channel group for each plurality of back channel uplinks is based on evaluating a traffic load for each plurality of back channel groups. 82. A method for transmitting a frame synchronized message, characterized in that it comprises: receiving a control node synchronization message in a transmission signal; determining an initial back channel frame time using the control node synchronization message; store an outgoing user message; and transmitting the outgoing user message during an assigned period after the initial frame time of the return channel, wherein the transmission frequency is determined by an assignment message received in the transmission signal. 83. The method according to claim 82, characterized in that it further comprises * evaluating the stored outgoing user message and transmitting an indicator of traffic accumulations. 84. The method according to claim 82, characterized in that the assignment-* message is associated with a first group of return channel, and the transmission frequency is in the first group of return channel. 85. The method according to claim 84, characterized in that the transmission frequency is changed to a different transmission frequency in the first turn channel group based on the allocation message. 6 T he m e t odo s s s s s s e s J 84, characterized in that the transmission frequency is changed to a different transmission frequency based on a traffic load factor. "« You »." • * > 87. The method according to rei indication 82, characterized in that the transmission frequency is changed from a first group of channel back to a different transmission frequency in a second group of channel back. 88. The method according to the rei indication 82, characterized in that it further comprises changing the transmission frequency to a different transmission frequency based on a random weighted frequency selection based on a traffic load factor. 89. The method according to claim 82, characterized in that it further comprises monitoring a previous back channel group and a current back channel group after the transmission frequency has been assigned to the current back channel group. 90. The method according to the indication rei 82, characterized in that the transmission frequency is changed to a frequency of bandwidth. ': XJ 96. The method according to the rei indication 82, characterized in that it also comprises the outgoing user message. 97. The method according to claim 82, characterized in that the outgoing user message is transmitted in a TDMA format. * 98. The method according to claim 97, characterized in that transmitting the outgoing user message includes transmitting an interval ALOHA burst message aligned with the initial time of the return channel frame. 99. The method according to claim 97, characterized in that the allocated period includes at least one time interval after the initial time of the return channel frame as determined by a distribution message of received bandwidth in the signal of, t ransmi s ion. 100. The method according to claim 82, characterized in that it further comprises comprising the outgoing user message using a lossless compression standard. 101. The method according to claim 82, characterized in that transmitting the message * Outgoing user includes modulating the transmission frequency using a Q.SK modulation St.yi scheme. X • 102. The method according to the rei indication 82, characterized in that it further comprises limiting the outgoing user message up to a maximum bandwidth less than the flow bandwidth. 103. A communication system for balancing the traffic on a plurality of return channels, characterized in that it comprises: a control station for transmitting a signal to a remote user, the transmission signal including a non-real time frame marker, a synchronization message, and a return channel control message; a receiver at the remote user to receive the transmission signal and determine an initial time frame of the return channel using the non-real time frame marker and the synchronization message; and a transmitter on the remote user to uplink a user message on a return channel of the plurality of channels A », back for a predetermined period after the initial frame time of the return channel, in which an uplink frequency on a back channel is determined by the back channel control message. « 104. The communication system according to claim 103, characterized in that a bandwidth of the return channel is determined by the return channel control message. 105. The communication system according to claim 103, characterized in that it further comprises a return channel controller at the control station, the back channel controller providing the return channel control message. The communications system according to claim 105, characterized in that the return channel controller further provides a message of distribution of bandwidth in the transmission signal which establishes a bandwidth of the return channel. 107. The communication system according to claim 106, characterized in that the bandwidth of the return channel is established <; based on a predetermined load factor. 108. The communication system according to claim 105, characterized in that the bandwidth of the return channel is established 5 when evaluating an indicator of accumulations of - «user transmitted by the remote user to the control station. * 109. The communication system according to the indication 108, characterized in that the bandwidth of the return channel is established in a flow bandwidth. 110. The communication system according to claim 108, characterized in that the uplink frequency of the 15-turn channel is established at a dedicated frequency based on an evaluation of the user accumulation indicator. 111. The communication system according to claim 105, characterized in that the back channel controller changes the uplink frequency to a different frequency within a first back channel group. 112. The communication system according to claim 105, characterized in that the • Back channel controller changes the uplink frequency to a different frequency within a second group of back channel. 113. The communication system according to claim 112, characterized in that the < The return channel controller changes the uplink frequency to a different frequency based on a load factor of the system. 114. The communication system according to claim 103, characterized in that a bandwidth of the return channel is determined by a bandwidth distribution request included in the user message uplinked by the remote user. 115. The communication system according to claim 114, characterized in that the user message is a burst transmission 20 of the ALOHA type. 116. The communication system according to claim 115, characterized in that the user message includes the request for distribution of bandwidth and an additional user message, having the message of «. 4kY & additional user a size smaller than the default threshold size. 117. The communication system according to claim 103, characterized in that the transmission signal is an asynchronous DVB transport stream. 118. The communication system according to claim 103, characterized in that it further comprises a plurality of remote users sharing the plurality of return channels and a return channel controller, wherein the return channel controller controls the link frequency. ascending of each plurality of return channels by the return channel control message. 119. The communication system according to claim 118, characterized in that the back channel controller controls a distribution of bandwidth for each? plurality of return channels. 120. The communication system according to claim 118, characterized in that a subset of the plurality of back channels are burst channels of ALOHA, and in which the back channel controller changes a "£ upstream user uplink - * from an ALOHA burst channel to a non-ALOHA burst channel according to the burst channel control message. 121. The communication system according to claim 120, characterized in that the # ALOHA burst channel is selected from the subset of the plurality of return channels by the remote user using a random weighted frequency selection criterion. 122. The communication system according to claim 120, characterized in that the non-ALOHA burst channel is selected by the control station using a group load factor. 123. The communication system according to the indication rei 103, characterized in that the transmission signal is encapsulated in an IP / DVB protocol layer. . and i 124. The communication system according to claim 103, characterized in that it further comprises a communications satellite for transmitting the transmission signal transmitted to the receiver. 125. A method for balancing loads between the groups of return channels in a communication system, characterized in that it comprises: requesting the bandwidth of the return channel in an uplink message coming from a remote user to a control station, including the uplink message an accumulation indicator; distribute at least one bandwidth of the back channel for the remote user when processing the accumulation indicator; providing a channel distribution message from the control station to the remote user in a transmission signal, wherein the channel distribution message allocates at least the bandwidth of the return channel; and transmitting a user message on a return channel according to the channel distribution message. *? 126. The method according to claim 125, further characterized in that it comprises distributing a back channel uplink frequency. 127. The method according to claim 1? A * turn channel uplink frequency includes skipping the frequency of an uplink frequency between a predetermined number of uplink frequencies according to a dynamic system traffic load. 133. The method according to claim 132, characterized in that distributing the uplink frequency of 10-turn channel by frequency hopping further depends on a plurality of accumulation indicators from a plurality of remote users. 134. The method according to claim 15 132, characterized in that the predetermined number of uplink frequencies is assigned to a back channel group. 135. The method according to claim 20 132, characterized in that skipping the frequency balances a traffic load within a first group of return channel. 136. The method according to claim 125, characterized in that requesting bandwidth of the return channel includes transmitting a * J5 ALOHA burst transmission from ** * J% * - «remote user. 137. The method according to the indication f 125, characterized in that the bandwidth of the allow a message e user smaller than a predetermined threshold size to link up. 138. The method according to claim .'- " 10 125, characterized in that a portion of available return channels are return burst channels of ALOHA. 139. The method according to claim 125, characterized in that the control station 15 periodically transmits a% load factor. group for each of the groups of channels of the • turn. 140. The method according to claim 125, characterized in that requesting the bandwidth of the return channel includes transmitting a first ALOHA burst transmission from the remote user in an ALOHA channel. 141. The method according to the indication 25 125, characterized in that it also comprises that the remote user sele of one of the groups use a base factor in a load of tr SUMMARY A communication system balances the message traffic between the groups of channel back-t and within the groups, so that the user does not control the specific transmission frequency used. The uplink frequencies and bandwidths for the return channels are established by the system in a control message of the back channel in the transmission signal in order to account for the load of the channel group of the return and the return channel. system, and to account for the accumulations of user messages. An initial transmission from a remote user can be made using a burst signal of the ALOHA type which provides a message accumulation to the control station, and is done at a certain frequency derived from a frequency selection process based on the load, compensated randomly. The system, and not the individual users, determines the frequency and channel distributions. For large accumulations or priority users, a bandwidth is provided or. { periodic lim. A method for balancing loads between the groups of back channels in the communication system includes requesting back channel bandwidth in an ascending message from a remote user to a control station. The uplink message may include both an indicator of accumulation as a request for distribution of bandwidth provided to a NOC Network Operations Center 'which can be used to establish the bandwidth and frequency of the return channel for the remote uplink. A user message is transmitted on the frequency of the designated return channel using the bandwidth v distributed according to the accumulation indicator and a bandwidth distribution request so that the loads of the traffic on the balance are maintained between the set back channel frequency groups, and within each frequency group of back channel