MXPA05002000A - Scheduler for a shared channel. - Google Patents

Abstract

A method, system and apparatus for scheduling data to subscriber stations from a base station over a shared channel. Data destined for each subscriber station is placed into queues at the base station. The base station allocates a portion of the shared channel to each particular queue based upon that queue's priority value. The priority value for each queue is determined by an adjusted QoS value and an adjusted throughput value. The QoS value indicates whether a subscriber station has been receiving data according to an agreed-upon QoS level. The throughput value indicates the data rate that can be achieved by transmitting to that subscriber station. These two values are examined by a scheduling policy at the base station. Scheduling policies can include scheduling data to emphasize fairness between subscriber stations, scheduling data to improve overall throughput, and scheduling data to achieve a balance between fairness and throughput.

Description

WO 2004/017650 A2 INI U NI 1 1 II li II III MUI 1: 1 I! III II I II Fortwo-letter codes and other abbreviations, referred to the "Guid-ance Notes on Codes and Abbreviations" appearm 'g atthe begin-ning or each regular issue of the PCT Gazette.

PROGRAMMER FOR A SHARED CHANNEL FIELD OF THE INVENTION The present invention relates to a system, a method and an apparatus for programming information in a network. More specifically, the present invention relates to a system, a method and an apparatus for programming information traffic in a shared channel.

BACKGROUND OF THE INVENTION In a network that includes a shared channel to deliver information traffic to multiple receiving stations of a single transmitting station, a transmitting station must determine how to allocate its link capacity between receiving stations. Examples of such network include networks and wireless information networks based on CATV such as the AMOSPHERE ™ system sold by the assignee of the present invention, etc. In the latter system, a transceiver of the base station will service a plurality of subscribed stations through an air interface that provides shared and dedicated link channels (base station to subscriber station). Because the transmission capacity of such systems is limited (typically by the bandwidth available), the allocation of available capacity among the users to ensure the efficient use of the transmission capacity and provide levels of 2 Acceptable service can be difficult. Consequently, such systems may benefit from programming transmissions appropriately in the compacted link (s). One of the simplest programming methods is the programming of all against all. The programming of iods against all provides each subscribing station with an equal amount of transmission time on the shared channel. Although this may be an advantageous method in some circumstances, in many networks, such as those that use radio-based links, not all subscriber stations will have the same information reception rates, due to factors such as signal-to-noise ratios (SNR) different. Thus, the division of all against all does not really provide an equal delivery of information in the shared link for each subscribing station. This inequality can result in unsatisfied subscribers, particularly those subscribers who use subscriber stations on the edge of the service area who have substantially lower average information rates than subscribers with subscriber stations located near the base station. In addition, this inequality requires that the service provider be conservative when announcing the operating capabilities offered by the system. Another known method of programming, division provides justly, provides each subscriber station with an adjusted amount of channel capacity in the shared link, where each subscriber station receives a part of the channel that is allocated to it.

It adjusts for its information reception rates, so that each subscribing station receives approximately the same average amount of information. Although fair proportional division can provide a better degree of equality between subscriber stations, it can also lead to a global drop in total system production, since the base station must devote a large amount of channel capacity to service a small minority. of subscriber stations with poor SNRs. In contrast to the two previous methods that focus on providing equal service to the subscriber stations, some other methods focus on achieving optimal production throughout the entire system, at the cost of impartiality between subscriber stations. In his article "CDMA / HDR: A Bandwidth-Efficient High-Speed Wireless Data Service for Nomadic Users" (IEEE Communication Magazine, July 20Q0 pp. 70-78), Bender and collaborators demonstrate how the unequal latency between subscriber stations with different information reception capacities (ie, different SNRs) can increase the total production in the lower link in the network. By providing a larger portion of channel capacity in the shared link to subscriber stations with better instant SNRs, the base station can transmit more global traffic. This method increases the total system ou, clearing potential delays and improving the overall performance of the network, but also creates latency and a lower information rate for subscriber stations with poorer average SNRs. For 4 To ensure that all subscriber stations have at least one tolerable individual information index, the system limits the maximum permitted value to subscriber stations with poorer SNR rates. Liu and colleagues in their article "Transmission Programming Timely Restrictions on Resource Division in Wireless Networks "(IEEE Journal on Selected Areas in Communication, Vol. 19, No. 10, October 2001, pp. 2053-2064) discuss the potential for improving wireless resource efficiency by exploiting variances in channel conditions, while still maintaining a level of impartiality between subscriber stations In its model, each subscriber station is allocated with a fraction of transmission time.The information packets are stored in traffic queues for each subscriber station until it arrives However, the base station continuously measures the quality of the link (which may vary over time) at each subscriber station, and transmits to the subscriber station as best as possible at that time. still provides an average index of information required to each subscriber station. Timely transmission can provide an increase in both total and individual production, not without its disadvantages. One disadvantage is that timely programming can increase the latency for subscriber stations as the base station waits for the opportune moment to transmit them to them. Another disadvantage is that 5 this method assumes a constant level of information to be transmitted, such as a WAP session on a cell phone. Nor does the opportune method contemplate intentional differences in the treatment of subscribers, such as those provided by different qualities of service (QoS), or for treatments of different types of media information. For example, a base station can service subscriber stations with different priorities, so that a subscriber using a Voice-over service? (VolP) intolerant to the latency receives a guaranteed service, while another subscriber is surfing the network and will be provided only with a service of the best effort by the base station. In their article "providing quality of service in a shared wireless link" (IEEE Communication Magazine February 2001, pp. 50-54), Andrews and colleagues describe a new programming algorithm, Modified Largest Weighted Delays First (M-LWDF) that It alleviates some of the previous ventures. The M-LWDF is similar to timely programming because it programs transmissions to take advantage of the fluctuations of the SNR. However, traffic flows in particular (traveling in the lower link to their respective subscriber stations) are given preferential treatment over other traffic flows by virtue of their QoS level. For each time slot (t), the base station calculates a value for each traffic queue, this value consisting of the product of the packet delay multiplied by the channel capacity for that subscribing station 6 multiplied by an arbitrary value. The traffic queue with the highest derived value is programmed. Mathematically, each time slot (t) serves a waiting pack queue (j) for which the function 7jWj. { t) rj. { t) is maximum. W (t) is the current waiting time for packets stored in queue j, r, (t) is the capacity of the channel, or index of information, for the flow / information, and y, is an arbitrary value. If y is the same for each packet queue, then all subscriber stations have the same QoS level. U na pack tail with a higher value for? Do you have a higher level of service than a packet queue with a lower value for? If r (t) is the same for each packet queue, then all subscriber stations have the same index of information. A packet queue with a higher value for r (t) thus transmits an average information index greater than another packet queue that has the same value of?. Although M-LWDF provided some advantage over the prior art, it also has its limitations. A key disadvantage is that M-LWDF does not provide a means to provide an impartiality policy between subscriber stations with different channel quality. Another disadvantage is that the M-LWD F can schedule traffic for only one subscriber station for a period of time. This creates a significant amount of latency (x number of time slots) for other subscribers waiting for package delivery. Furthermore, since each period of time carries information traffic for a single subscribed station, it is possible that some of the capacity of that time slot will be depleted due to the loss of time.

Internal fragmentation Therefore, it is desired to provide an information transmission scheduler that provides differentiated QoS service to subscriber stations while offering service providers the ability to implement programming policies designed to provide sector production, impartiality among their signers, or some combination of the two. It is also desirable to implement a programmer for transmitting information that is timely and that can take advantage of the variance in the facets of receiving information from subscriber stations served by the transmitter. Finally, the programming mechanism must be flexible enough to accommodate a wide variety of computing capabilities at the base station.

B REVE DESCRITION OF THE INVENTION It is an object of the present invention to provide a novel information transmission program that obviates or mitigates at least some of the previously identified disadvantages of the prior art. According to a first aspect of the present invention, there is provided a method for programming information for transmission from a base station in a shared channel to a plurality of subscriber stations, said method comprising: Determine a factor of impartiality from a number of 8 possible impartiality factors, where a first end of said range indicates a policy to program information with maximum impartiality between said plurality of subscriber stations and a second end of said range indicates a policy to program information for maximum information traffic in said shared channel. For each subscriber station in said plurality of subscriber stations to which said base station has information to be delivered: Determine a quality of service priority value, said quality of service priority value indicating a priority of said subscriber station in relation to to other subscriber stations in said plurality of subscriber stations; Determine a production value, said production value that indicates the amount of information that is to be moved to said subscriber station if information is programmed to said subscriber station; To determine a total priority value, said total priority value is the sum of said quality of service priority adjusted according to said impartiality factor and said production value adjusted in inverse manner according to said impartiality factor; and scheduling information in a portion of said shared channel for at least one of said plurality of subscriber stations, beginning with the subscribing station with the total priority value 9 higher. According to another aspect of the present invention, there is provided a system for transmitting information, comprising: A plurality of subscriber stations each having a processor, a meter, a radio and an antenna, each subscribing station operable to transmit a request for a dedicated information channel from a base station; and A base station having a processor, a modem, a radio and an antenna, and operable to receive said requests for a dedicated information channel from said subscriber stations and to program information for transmission to said plurality of subscriber stations in a shared channel in accordance with a programming policy that varies priorities between programming for impartiality between subscriber stations and for improved production for said plurality of subscriber stations. The present invention provides a method, a system and an apparatus for programming information for a plurality of subscriber stations from a base station in a shared channel. The information destined for corpus subscriber station is placed in individual queues in the base station. The base station allocates a portion of the shared channel to transmit the information in each particular queue based on a priority value it assigns to that queue. The priority value for each queue is determined by a value of the QoS and a production value, where each of these two values is adjusted by a factor of impartiality. The value of 10 QoS indicates if a subscribing station has been receiving in-fonnation from the base station according to an agreed QoS level. The production value indicates the index of information that can be achieved by the base station. that transmits that subscribing station. The impartiality factor represents a programming policy in the base station. Programming policies can include information scheduling to emphasize impartiality between subscriber stations at a particular QoS level, schedule information to maximize production in the shared channel, and schedule information to achieve a balance between impartiality and maximum production.

BRIEF DESCRIPTION OF THE DRAWINGS Now embodiments of the present invention will be described, by way of example only, with reference to the accompanying figures, wherein: Figure 1 is a schematic representation of a wireless network according to an embodiment of the invention; Figure 2 is a representation of a communication link as shown in Figure 1, constituted by multiple channels; Figure 3 is a schematic representation of the base station shown in Figure 1; Figure 4 is a schematic representation of one of the 11 Subscriber stations shown in Figure 1; Figure 5 is a schematic representation of a programmer for a shared channel running in the base station shown in Figure 3; Figure 6 is a flowchart showing how the lower-broadcast broadcast channel programmer shown in Figure 5 manages (to schedule delayed traffic flows to the shared channel.

DETAILED DESCRIPTION OF THE INVENTION Referring now to Figure 1, a wireless network for transmitting information is generally indicated at 20. The network 20 includes a radio base station 24 and a plurality of subscriber stations 28a, 28b ... 28n. In a currently preferred mode, the radio base station 24 is connected to at least one information telecommunications network. (river shown), such as a switched information network based on landline, a packet network, etc. , through an appropriate gate and one or more retracements (not shown), such as a land line link T1, T3, E1, E3, OC3 or other suitable link, or it may be a satellite or other radio or channel link microwave or any other suitable link for the operation as a backlash as it may occur to those skilled in the art. The base station 24 is co mmunicated with subscriber stations 28 12 which can be fixed, nomadic or mobile devices. The number "n" of subscriber stations that receive service from a base station 24 may vary depending on the amount of radio bandwidth available and / or the configuration and requirements of the subscriber stations 28. As illustrated in the Figure 1, the geographic distribution of the subscriber stations 28 with respect to the base station 24 need not be symmetric nor the subscriber stations that are physically located close to each other will necessarily experience the same or similar indexes of information reception, due to the relationships Signal-to-radio frequencies (SNRs) experienced at subscriber stations 28 due to a variety of factors including the geographical environment (the presence or absence of buildings that can reflect or mask the signals), the radio environment (the presence or absence of sources of radio noise), etc. Thus, in most circumstances the subscriber stations 28 served by a base station 24 may have significantly different SNRs and these S N Rs may change over time. As is known to those skilled in the art, the stations of their cryptoses 28 can be divided geographically into different sectors 36, formed by means of directional antennas in the base station 24 to increase the number of subscriber stations 28 that can be be served from a single base station location. In such a case, each sector 36 acts essentially as 13 a different base station and base station 24 may administer the resources of the network in each sector 36 independently of each other sector 36. Although Figure 1 shows only one base station 24, it will be apparent to those skilled in the art as well. The network 20 may contain multiple geographically distributed base stations 24, with coverage of overlapping sector 36 of subscriber stations 28, and where each subscriber station 28 in a coverage area of overlap sector 36 may select which base station 24 will give it service A communication link 32 is established in each sector 36 between the base station 24 and each subscriber station 28 in sector 36 via radio. AND! communication link 32a carries information to be transferred between base station 24 and subscriber station 28b, communication link 32b carries information to be transferred between base station 24 and subscriber stations 28c and 28d, etc. The communication link 32 can be implemented using a variety of multiple access techniques, including TD A, FDMA, CD MA or hybrid systems such as GS M, etc. In a current mode, information transmitted by link 32 of communication is transmitted using CD MA as a multiple access technology and the information is in the form of packets, transmitted in spaced time frames, whose details will be discussed with more detail below. As it is in the present, the terms "package", "packaged" 14 and "packaging" refers to the overall arrangement of the transmission of the information packaged for reception at a intended recipient of destination. The packaging of information may include, without limitation, applying different levels of codes (from non-coding to high levels of coding and / or different coding methods) of forward error correction (FEC), employing several levels of symbol repetition , employing different modulation schemes (4-QAM, 16-QAM, 64-QAM, etc.) and any other techniques or methods to arrange transmission of information with a selection of the amount of radio resources (or other physical layer) required , the information regime and the probability of transmission of errors that are appropriate for the transmission. For example, the information can be packed with a rate of ¼ FEC coding (each 1-bit information is transmitted in 4 bits of information) and 16-QAIvl modulation for transmission to a first destination receiver and packed with a régimen FEC scheme of 64-QAM coding and modulation for transmission to a second destination receiver which has a better reception quality than the first. The communication link 32 operates in both link directions above (from a subscriber station 28 to the base station 24) and link down (from a base station 24 to subscriber stations 28). The method for providing both link directions above and link down is not particularly limited, and in the present embodiment the communication link 32 operates by duplexing the frequency division (FDD). However, within 15 According to the invention, there are other methods for providing both an up link and a down link address, such as time division duplex (TDD) and hybrid schemes. Referring now to Figure 2, in the present embodiment, the communication link 32 is constituted by a plurality of channels, which in the present CDMA implementation, is achieved with the orthogonal coding of the link 32. In the link address abajó, the base station 24 uses a shared channel, referred to as the broadcast information channel (BDCH) 38 to carry variable and full rate traffic (consisting mainly of signaling traffic and Internet) through a sector 36. The BDCH 38 makes use of adaptive FEC to maximize link capacity below and contains multiple packets or, more commonly, information packet segments of various subscriber stations 28 all multiplexed in time together into a single frame. In the present modality, the BDCH 38 can be configured with extension factor 4, where 8 blocks of information can be sent in a frame of 10 milliseconds, the extension factor 8 where 4 blocks of information can be sent in one frame, or extension factor 16 where 2 blocks of information can be sent in a frame. Also, in the present embodiment, the base station 24 can support one or more BDCH 38 per sector 36 at any time. In the link-up address e) information traffic is carried from the subscriber station 28 to the base station 24 using a 16 dedicated information channel (DDCH) 44, A separate DDCH 44 is established between the base station 24 and each subscriber station 28 with an active communications link 32. The traffic signaling is carried from the subscriber station 28 to the base station 24, typically in band using DDCH 44. The subscriber stations 28 measure their received SNR, or another metric of their ability to receive information from the base station 24 and report this information again to the base station 24 or on a regular basis in its DDCHs 44 using a higher layer signaling protocol. The subscriber stations 28 with high SNRs require less channel coding and can use higher order modulation than the subscriber stations 28 with lower SNRs and thus, each block transmitted in BDCH 38 using a different type of block (i.e., different type packaging). of FEC, FEC regime, modulation, etc.). Figure 3 shows an example of a base station 24 in greater detail. For the sake of clarity, the base station 24 shows an example of a single-sector base station. However, multiple-station base stations 24 are also within the scope of the invention. The base station 24 comprises an antenna 50, or antennas, for receiving and transmitting radiocommunications on the communication link 32. In turn, the antenna 50 is connected to a radio 52 and a modem 54. The modem 50 is connected to a microprocessor router assembly 16 such as a system based on a Pentium processor from Intel Corporation using a conventional operating system such as 17 Linux The 56 microprocessor router assembly is responsible for traffic programming of all stations 28 subscribers in its section 36 and for radio resource management. It will be understood that the assembly 56 may include multiple microprocessors, as desired and / or that the router may be provided as a separate unit, if desired. The router within the microprocessor router assembly 56 is connected to a rear carrier 58 in any suitable manner, which in turn connects the base station 24 to an information network (not shown). Referring now to Figure 4, a subscriber station 28 is shown in more detail. The subscriber station 28 comprises an antenna 60, or antennas, for receiving and transmitting radiocommunications on the communication link 32. In turn, the antenna 60 is connected to a radio 64 and a modem 68, which in turn is connected to a microprocessor assembly 72. The microprocessor ehsamble 72 may include, for example, a StrongARM processor manufactured by Intel Corporation, which performs a variety of functions, including the implementation of conversion from A / D to D / A, filters, encoders, decoders, information compressors, decompressors and / or disassembly of packages. The myroprocessor assembly 72 also includes dampers 74 that store queued information traffic awaiting transport of the communication link 32. As shown in Figure 4, the microprocessor assembly 32 interconnects with a modem 68 and a port 76 of 18. information, to connect the subscriber station 28 to an information client device (not shown), such as a personal computer, a personal digital assistant or the like which is operable to use the information received by the communication link 32. Accordingly, the microprocessor assembly 72 is operable to process information between the information port 76 and the modem 68. The microprocessor assembly 72 is also interconnected with at least one telephony port 80, to connect the subscriber station 28 to a telephone device, (not shown) such as a telephone. In some cases, particularly in the case of a mobile subscriber station 28, the customer information device may be integrated with the subscriber station 28. Referring now to Figure 5, the logical architecture of a shared channel, such as a. BDCH programmer. The scheduler 100 is responsible for allocating queued information packets destined to be transmitted from the base station 24 to the subscriber stations 28 in the bitstream of the BDCH 38 while maintaining any agreed upon QoS terms for each subscriber station 28 and implementing a programming policy based on a factor of impartiality provided by a network operator (and discussed in more detail below) in order to provide varying degrees of impartiality priority between subscriber stations 28 and global production at BDCH 38 A method for programmer 100 to implement a programming policy and program packets in the queue is described below with reference to Fig. 6. In the current mode, the scheduler 100 is a software program that runs in the base station 24 in the microprocessor assembly 56. However, other implementations, such as a hardware or firmware implementation, are also within the scope of the invention. The information 102 pasted for each subscriber station 28 is formed in traffic queues 104 before being sent downstream in the BDCH 38 to several subscriber stations 28. Each information flow 102 may contain a variety of different types of information such as web pages, FTP information, classified media, voice in IP information, or other types of information as will occur to those skilled in the art. The traffic queues 104 for the subscriber stations 28 are set for each subscriber station 28 which is known to, and is connected to, the base station 24 by the communication link 32. The example of Figure 5 shows a scenario with 4 traffic queues 104, each serving a flow for a corresponding subscriber station 28 (for example, queue 104a contains limited traffic for subscriber station 28a, etc.). ). In the example shown in the Figure, the traffic queue 104a has five queued packets, the 104b has no queued packets, the traffic queue 104c has three queued packets, and the traffic queue 104d has four packets queued. The traffic queues 104a, 104c and 104d therefore have delayed flows (eg, queues of non-zero length) while that the queue '104b of traffic has no delayed flow. In addition to containing the traffic queues 104n, the scheduler 100 stores the link quality parameter 108n, the negotiated service share parameter parameter 112n, and the measured service share parameter 116n, parameters for each station 28n active subscriber with a flow of traffic. In addition, programmer 100 stores a factor of fairness. As described in more detail below, there is at least one instance of fairness factor 120 per sector 36. The link quality parameter 108n contains an adequate measurement of the reception quality experienced in subscriber station 28n. (subscription 2ßp subscriber) - In a present embodiment, the value of link quality parameter 108 is the subscribed 2ß = |¾ estimated signal-to-noise (SNR) assertion of at least one suitable channel, where Ec represents the BDCH channel signal energy per chip in the antenna of the subscriber station 28, and Nt represents the total noise received in the antenna 60 of the subscriber station 28, the total noise that is equal to the sum of the average density of the subscriber station. noise, the interference of other cells and interference sectors, plus the interference of multiple trajectories. In the present embodiment, each subscriber station 28n periodically updates its value for the link quality parameter 108 by transmitting its received SNR by a link channel above such as DDCH 44. The negotiated service share parameter 112n stores the value for a quality agreed on service level 21 (F? ßß) for station 28n subscriber. In this modality, the negotiated service participation parameter represents a guaranteed information rate (bits / s); however, other definitions of a negotiated service share such as maximum delay before transmitting a standby packet, or a combination of guaranteed information rate and maximum delay, are within the scope of the invention. The subscriber stations 28 with higher values for the negotiated service share parameter 112 will receive better service than the subscriber stations 28 with a lower negotiated service share parameter 112. In the present embodiment, the negotiated service share parameter 112 is negotiated between the base station 24 and each subscriber station 28 when the subscriber station 28 is contacted.; to the base station 24. However, the means for determining the negotiated service share parameter 112 are not particularly limited. For example, the negotiated service share parameter 112 may be determining by means of the service provided on the basis of the type of media to be transmitted to the subscriber station 28, a monthly subscription agreement for subscriber station 28, a payment per service, etc. Other methods for determining the negotiated service participation parameter 112 will occur to those skilled in the art. Measurement service parameter 116n stores the value of the measured service share (< ¾, ed) for station 22 28n subscriber. ?? measured shared service is the portion of BDCH 38 that has transported packets destined for that particular subscriber station. Thus, a larger value for parameter 1 16n of participation < Metered service indicates a higher average information regime delivered to that subscriber station. The median service share parameter 1 16n can be matched to the average bit rate in a fixed time interval for a particular subscriber station 28n. Finally, the fairness factor 120 is an adjustable parameter (F) that represents the programming policy and this parameter controls the equilibrium between impartiality of in-bound fl ow versus global production by the communication link 32. There may be either an impartiality factor 120 presence per sector 36, which is established by a network operator, or there may be an impartiality factor 1 20 presence per BDC H 38 (in cases where there is more than one BDCH 38 per sector 36). In the current mode, F is normalized and fluctuates from zero to one. A setting of zero indicates a policy that gives priority to the programming of the flows 1 02 of information to give priority to the production in the link below programming information to the stations 28 subscribers with the best SN Rs, without taking into account account the provision of impartiality between subscriber stations. An establishment of one that indicates a policy that gives priority to the flow schedule 1 02 to provide impartiality between subscriber stations 28 so that all stations 28 subscribers in the 23 Same level of QoS will receive the same information regime, regardless of their respective SNRs. Once the packets in a traffic queue 104 are programmed by the scheduler 100, they are moved to the frame blocks 128 of the BDCH 38. Normally the extension factor of a BDCH 38 is predetermined by a network operator and is fixed for each subscriber station 28 that is serviced by a particular BDCH 38. In a current embodiment, a tension factor of 4 is preferred (thus providing eight blocks 128 per frame 124). As is known to those skilled in the art, the structure of a block 128 may vary according to the differences in order of modulation, repetition of symbols, etc. The number of information bits carried in each block 128 may vary according to the block structure used. In a current mode, each block 128 may carry between three hundred and twenty-nine thousand seven hundred and fourcientbs bits of information. Generally, blocks 128 with smaller information advancements use lower order modulation and higher symbol repetition to provide greater redundancy for noisy or otherwise poor communication links 32 experienced by subscriber stations 28 with low SNRs. Communication with subscriber stations 28 with better SNRs can employ a block structure that carries more bits of information. In a current mode, blocks 128 with different structures of 24 block can be carried in the same frame 124. Referring now to Figure 6, a flow chart of an information transmission programming method for a BDCH 38 is shown starting at 200. In the current mode, the method described later it is run once by frame 124 programmed. However, the frequency of the method is not particularly limited and can be run more or less frequently than what is described herein, if desired. In step 200, a scheduling policy is determined by setting a value for the impartiality factor 120 for sector 36 (between 0 and 1) in the base station 24. As described above, a value of 0 indicates a programming policy where the programmer 100 gives priority to the production of the sector on the impartiality between the subscriber stations 28 and a value of 1 indicates a programming policy where the programmer 100 transmits queued packets with maximum impartiality to the subscriber stations 28. It is contemplated that, in most deployments, a factor of fairness of approximately 120 between the two limits of this range (zero and one) will be preferable. For example, an establishment of 0.5 would provide a policy that provides a reasonable degree of impartiality for most subscriber stations 28, while still taking advantage of SN variances to maximize link production below. It should be noted that even when the impartiality factor 120 is set at 25 one (indicating maximum impartiality, the subscriber stations 28 with different levels of QoS 112, will be programmed differently according to their QoS levels, since the impartiality factor of 120 determines the impartiality in the programming only with respect to SN s In order to provide totally equal service, the QoS levels 112 must be the same for all subscriber stations 28. In step 204, the scheduler 100 receives link quality parameter 108 for each subscriber station 28 delayed traffic (ie, any subscriber station 28n whose corresponding traffic queue 104n has at least one packet in it). Link quality parameter 108 can be updated in each repetition through the method, or it can be updated in intervals appropriate lengths In step 208, the scheduler 100 calculates a value for the priority (qf) based on QoS for each tail 104 of traffic that has at least one packet in the queue for this frame. q is a positive number between 0 and 1, with the highest values indicating a higher priority for that queue 104. A value for qf greater than 0.5 indicates that the information in queue 104 is lagging (i.e., parameter 116 of measured shared service is less than the shared service negotiated in negotiated shared service parameter 112) and a value of qr less than 0.5 indicates that that particular queue 104 is at the top in service (i.e., shared service parameter 116) measured is greater than the shared service negotiated in service parameter 112 shared negotiated). A higher value implies that the information in queue 1 04 requires faster service. The value for is derived first by subtracting a shared service required from the shared service measured, dividing the difference between two after adding 0.5: Both y (described further below) are defined as fluctuating between zero and one, so that it is always a number between zero and one. The required shared service represents the quantity of the shared service required to achieve a negotiated service participation parameter 1 12. For each frame that queue 104 is delayed, the service share required increases. In the current mode, it is calculated as follows: where the numerator is the product of the number of frames delayed for the flow 1 02 in a frame sliding interval (w / -) and is the parameter 12 of negotiated service share, negotiated in the installation. The absolute value notation is used to indicate the length of the vector, and B (n) is the indexes of the flows that are delayed 27 during frame n. The denominator is the sum of negotiated service parts of all queues 104 delayed in the same frame sliding interval. The measured service (< Pfraed) participation is determined by taking all bits transmitted in the BDCH 38 for the queue 104 selected during a sliding window interval, and dividing it among all the bits transmitted in the BDCH 38 during the same sliding interval of window for each queue 104. In the current mode, < Pfmetj is calculated as follows: ? * »). where bf (n) is the number of bits transmitted from the flow f during the frame n. In step 212, the scheduler 100 calculates the production priority (tf) for each queue 104 delayed for this frame. ff is a normalized interpretation of Ja SNR for a particular flow 102 (f), giving a value between 0 and 1, where 0 indicates a minimum SNR ratio and 1 indicates the maximum possible SNR. Mathematically: blfXa < S)) - b (p! Mi!) Tf - -j e b [asaxj-b (C (mJa) where b (x) is the number of bits in block 128 to x SNR, as determined by the block structure. In step 216, the programmer 100 calculates the function of 28 total priority (pf) for each queue 104 delayed by calculating a value derived from adding the QoS priority (qf, as determined in step 208) to the production value (tf, as determined in step 212), where each priority is multiplied by the impartiality factor 120 or an inverse of the impartiality factor 120, respectively. In the current mode, pf is calculated as follows: where B is the set of all tails 104 delayed. In the previous equation, F is the factor of impartiality 120. When the impartiality factor 120 is zero, then the product of F and q, is zero and the term. { a! SS (f) (1 -F)), which is the production value, is maximum. When the fairness factor 120 is one, then qf is maximum and the production value is multiplied for a product of zero. In step 220, all delayed tails 104 are sorted by the total priority function (? ') Determined in step 212 in descending order, in step 224, starting with queue 04 with the value p' (1) of highest total priority, the programmer 100 calculates the maximum number of blocks 128, referred to herein as (m '(¡)), which will be allocated to this queue 104 by calculating a percentage of available blocks 128 for that, based on the priority of this queue 104 relative to the sum of all the total priority values for all delayed queues. IVLás specifically, the programmer 100 29 multiply the number of blocks 128 in frame 124 (M) by the priority function (pf) for this queue 104 (as determined in step 212), dividing the result by the sum of all priority functions (also determined in step 212) for all delayed queues. In the current mode, the maximum number of blocks 128 m '(i) is determined as follows: m '(i) ~ round where the round operator () rounds the number of programmed blocks, m '(i), to the nearest integer. In step 228, starting with the highest priority queue 104. { p '(1)), programmer 100 places up to m' (1) blocks 128. Very few blocks 128 are placed if the number of bits available to program for queue 104 (p '(1)) requires less than m' (1) blocks 128. Step 220 is repeated for all delayed 104 queues (p '(2)), p' (3)), etc., until either all delayed 104 queues are cleared or all blocks 128 in frame 124 are programmed. Once step 220 is completed, the method returns to step 204 to program the next frame 124. The method continues as long as information is present to be programmed for transmission. Although the embodiments discussed herein are directed to specific implementations of the invention, it will be understood that the combinations, subsets and variations of the embodiments are within the scope of the invention, for example, in the embodiment of the invention.

Currently, only one queue is programmed for each traffic block 128. However, multiple queues can be programmed in a traffic block 128 and are within the scope of the invention. If multiple subscriber stations 28 are programmed in the same block 128, the block structure must be adequate to satisfy the SNR requirements of all scheduled subscriber stations. One way to ensure this, for example, is to only place subscribers that have an SNR that is greater than the first subscriber that is placed in the block. It is contemplated that the scheduler 100 may run less frequently when the total amount of traffic on all the queues 104 is below a certain threshold (representing a low amount of information traffic volume), such as to reduce the latency for the assembly. microprocessor router. Alternatively, when the total amount of traffic is below a certain threshold, the scheduler 100 may choose to suspend its programming method (as described with respect to Figure 6) and instead of program traffic according to some other method of programming such as FIFO, in order to reduce the latency for each queue 104. It is further contemplated that the scheduler 100 may run more frequently than once per frame 124, where the programming frequency is an integer multiple of the * duration of the block 128. This will allow the programmer to function well in situations where the coherence time of the flute is smaller, such as when the carrier frequency is greater or if there is a greater amount of pedestrian movement or other traffic near the subscriber or base station. It is also not intended that the present invention be limited to use with the particular radio-based system described above, nor to radio-based systems in general, and it is believed that the present invention can be advantageously employed with any system for programming information for transmission. from a single node to one or more of a plurality of other nodes in a shared communication link. Use is contemplated with optical communication links, with wire and other shared links. The above described embodiments of the invention are intended to be examples of the present invention and alterations and modifications may be made thereto by those skilled in the art, without departing from the scope of the invention which is defined solely by the claims attachments to this.

Claims (25)

32 CLAIMS

1. A method for programming information for transmission from a base station in a shared channel to a plurality of subscriber stations, said method comprising: determining a factor of impartiality from a range of possible impartiality factors, where a first end of said range indicates a policy for programming information with maximum impartiality between said plurality of subscriber stations and a second end of said range indicates a policy for scheduling information for maximum information traffic in said shared channel; • for each subscriber station in said plurality of subscriber stations for which said base station has to deliver information to: determine a service priority value quality, said quality of service priority value indicating a priority of said subscriber station with disclosure to other subscriber stations in said plurality of subscriber stations; determining a production value, said production value indicating the amount of information to be moved to said subscriber station if the information is programmed for said subscriber station; determine a total priority value, said total priority value is the sum of said adjusted priority service quality of 33 according to said factor of impartiality and said production value adjusted inversely according to said factor of impartiality; and program information in a portion of said channel! shared to at least one subscriber station of said plurality of subscriber stations, beginning with the subscriber station with the highest total priority value. The method of claim 1, wherein said quality of service priority value is determined by comparing said negotiated service share with said measured service share, wherein said quality of service priority is greater when said negotiated service share is greater than said measured participation and said quality of service priority value is low when said measured participation is greater than said negotiated service participation. 3. The method of claim 1, wherein said production value is calculated by determining the largest block format that can be received at said subscriber station in said plurality of subscriber stations. The method of claim 3, wherein said determining the largest block format that can be received in said each subscriber station occurs by determining the signal to noise ratio received in said subscriber station of said plurality of stations Subscribers The method of claim 4, wherein said portion of said shared channel programmed for said at least one Subscriber station of said plurality of subscriber stations is proportional to said total priority value for said at least one subscriber station. The method of claim 5, wherein said method occurs at least once per frame in said shared channel. 7. A system for transmitting information, comprising: a plurality of subscriber stations, each having a processor, a modem, a radio and an antenna, each subscriber station operable to receive information traffic from a base station; and a base station having a processor, a modem, a radio and an antenna, and which can be operated to receive said requisitions for a dedicated information channel from said subscriber stations and to program information for transmission to said plurality of subscriber stations in a shared channel according to a programming policy that varies priorities between programming for impartiality between subscriber stations and to improve production for said plurality of subscriber stations. The system of claim 7, wherein each subscriber station of said plurality of subscriber stations can be operated to negotiate with said at least one base station a negotiated service share of said shared channel for information traffic limited to said each station. Subscriber 9. The system of claim 8, wherein said station 35 base determines a quality of service priority value for each subscriber station and said plurality of subscriber stations by comparing a service share negotiated for said each subscriber station with a service share measured for said each subscriber station. The system of claim 9, wherein said base station determines a production value for said each subscriber station in said plurality of subscriber stations by determining the largest block format that can be received in said subscriber station in said plurality of subscribers. Subscriber stations. The system of claim 10, wherein said base station determines the largest block format that can be received in said each subscriber station occurs by determining the signal to noise ratio received in said subscriber station of said plurality of subscribing stations. The system of claim 11, wherein said subscriber station of said plurality of subscriber stations transmits an indication of their signal to noise ratio to said base station. 13. A system for transmitting information, comprising: a plurality of subscriber stations, each having a processor, a modem, a radio and an antenna, each subscriber station operable to receive information traffic from a base station; and 36 at least one base station, said at least one base station having a processor, a modem, a radio and an antenna, and which can be operated to program information traffic for each of said plurality of subscriber stations in a channel shared in accordance with the method described in claim 1. 14. The system of claim 13, wherein each subscriber station of said plurality of subscriber stations can be operated to negotiate a service share with said at least one base station. negotiated from said shared channel for information traffic limited to said each subscribing station. The system of claim 14, wherein said base station determines a quality of service priority value for each subscriber station in said plurality of subscriber stations by comparing a service share negotiated for said subscribing station with a service share measured for said each subscribing station. The system of claim 15, wherein said base station determines a production value for said each subscriber station in said plurality of subscriber stations by determining the largest block format that may be received in said subscriber station in said plurality of subscribers. Subscriber stations. 17. The system of claim 16 > wherein said base station determines the largest block format that can be received in said each subscribing station occurs determining the ratio of 37 signal to noise received at said subscriber station of said plurality of subscriber stations. The system of claim 17, wherein said subscriber station of said plurality of subscriber stations transmits an indication of their signal to noise ratio to said base station. The system of claim 18, wherein said base station schedules information traffic for each of said plurality of subscriber stations in a shared channel according to the method described in claim 1 provided that the total amount of information traffic reach at least one predetermined threshold and program information traffic for each of said plurality of subscriber stations according to another method as long as the total amount of information traffic is below said predetermined threshold. 20. A base station having a microprocessor, a modem, a radio and an antenna and operable to schedule information traffic for a plurality of subscriber stations in a shared channel according to the method described in claim 1. 21 The base station of claim 20, wherein said base station determines a quality of service priority value for each subscriber station in said plurality of subscriber stations by comparing a negotiated service share for said subscribing station with a service share 38 measure for each subscribing station. 2

2. The base station of claim 21, wherein said base station determines a production value for said each subscriber station in said plurality of subscriber stations by determining the largest block format that can be received in said each subscriber station in said subscriber station. plurality of subscriber stations. 2

3. The base station of claim 22, wherein said base station determines the largest block format that can be received at said subscriber station occurs by determining the signal to noise ratio received at said subscriber station. of said plurality of user stations. 2

4. The base station of claim 23, wherein each subscriber station of said plurality of subscriber stations transmits an indication of their signal to noise ratio to said base station. 2

5. The base station of claim 24, wherein said base station programs information traffic for each of said plurality of subscriber stations in a shared way according to the method described in claim 1 provided that the Total amount of information traffic reaches at least a predetermined threshold and programs information traffic for each of said plurality of stations its scriptors according to another method provided that the total amount of information traffic is below dich or default threshold.