MXPA99011941A - Dynamic bandwidth allocation to transmit a wireless protocol across a code division multiple access (cdma) radio link - Google Patents

Abstract

A technique for transmission of wireless signals across CDMA radio links. Bandwidth is allocated dynamically within a session to specific CDMA subscriber unit based upon data rate determinations. Specifically, a dynamic bandwidth allocation algorithm operates from limits calculated based upon available ports per subscriber, expected user bandwidth, and parallel user bandwidth versus throughout. Provisions for priority service, unbalanced forward and reverse spectrum utilization, voice prioritization, and band switching are also made.

Description

DIN MICA ASSIGNMENT OF BANDWIDTH TO TRANSMIT A WIRELESS PROTOCOL TO THROUGH AN ACCESS RADIO LINK MULTIPLE BY CODE DIVISION (CDMA) BACKGROUND OF THE INVENTION The increasing use of wireless phones and personal computers by the general population has led to a corresponding demand for advanced telecommunication services that were once considered only for use in specific applications. For example, in the late 1980s, wireless voice communication such as that available with mobile telephony has been the exclusive domain of the businessman due to the high expected subscriber costs. The same was also true for accessing remotely distributed computer networks, so that until very recently, only business people and large institutions could acquire the necessary computers and wireless access equipment. However, the general population now wants more and more to not only have access to networks such as the Internet and private intranets, but also to access networks of this type in a wireless way. This is particularly a concern of the users of laptops, folding laptops, manual digital personal assistants and the like, who would prefer to access such networks without being linked to a telephone line. There is not yet a widely available solution available to provide high-speed, low-cost access to the Internet and other networks using existing wireless networks. This situation is most likely an artifact of several unfortunate circumstances. For example, the typical way of providing high speed data service in the business environment over the cable line network is not easily adaptable to the voice grade service available in most homes or offices. Additionally, such standard high-speed data services do not by themselves lead to efficient transmission over standard cellular wireless handsets either. Additionally, the existing cellular network was originally designed only to provide voice services. At present, the wireless modulation schemes in use continue their focus on supplying voice information with maximum data rates only in the 9.6 kbps range that is readily available. This is because the cellular switching network in most countries, including the United States, uses analog voice channels that have a bandwidth from approximately 300 to 3600 Hertz. A low frequency channel of this type does not by itself directly lead to transmit data at speeds of 28.8 kilobits per second (kbps) or even the speed of 56.6 kbps that is now commonly available using cheap cable line modems , and whose speeds are now considered to be the minimum data rates acceptable for Internet access. Switching networks with higher speed building blocks are just beginning to be used in the United States. Although certain cable line networks, called Integrated Services Digital Networks (ISDN), capable of higher speed data access have been known for some years, their costs have only recently been reduced to the point where they are attractive to the public. residential customer, even for cable line service. Although such networks were known at the time when cellular systems were originally deployed, for the most part, there is no provision for providing ISDN grade data services over cellular network topologies. European Patent Application EPO 719 062 A2 describes a system and network architecture for providing dynamic allocation of bandwidth / channel. In this system, the bandwidth supply is dynamically adjusted according to the selected service levels. For example, basic telephone service, ISDN service without links, wireless data service, wireless multimedia service, and other services such as broadcast video, are supported within the system by assigning a suitable number of channels to support each of them. said service demands.

COMPENDIUM OF THE INVENTION The present invention provides high speed voice and data service over standard wireless connections through a unique integration of existing cellular signaling and protocols as is available with Modulated Code Division Multiple Access (CDMA) systems. The present invention achieves high data rates through more efficient allocation of access to CDMA wireless channels. In particular, a number of subchannels are defined within a standard CDMA channel bandwidth such as by assigning different codes to each subchannel. The bandwidth requirements at each time of each online subscriber unit are satisfied by dynamically assigning multiple subchannels of the RF carrier on a basis according to the needs for each session. For example, multiple subchannels are granted during times when subscriber bandwidth requirements are relatively high, such as when web pages are loaded and released during times when the content of the line is relatively light, such as when the subscriber is reading a Web page that has previously been loaded or is performing other tasks. The subchannel allocation algorithms can be implemented to offer several priority service levels to particular subscribers. These can be assigned based on the available ports per subscriber, the user's expected bandwidth, service fee payments, etc. According to another aspect of the invention, some part of the available bandwidth is initially allocated to establish a communication session. Once the session has been established, if a subscriber unit does not have data to be presented for transmission, namely, if the data path remains inactive for some period of time, the previously assigned bandwidth is unassigned. Additionally, it is preferable that not all the previously assigned bandwidth be unassigned, but that at least some portion be kept available for use by a subscriber who is in session. If the inactivity continues for an additional period of time, then even the remaining portion of the bandwidth can be unassigned from the session. A logical session connection in a protocol- of the network layer is still maintained even if sub-channels are not assigned.

In a preferred device, an individual sub-channel is maintained for a predetermined minimum idle time for each connection of the network layer. This helps a more efficient management of the establishment and interruption of the channel.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of the preferred embodiments of the invention, as illustrated in the accompanying drawings, in which reference characters similar refer to the same parts throughout different views. Figure 1 is a block diagram of a wireless communication system that makes use of a bandwidth management scheme according to the invention. Figure 2 is a layered protocol diagram of the Open System Interconnection (OSI) type showing where the bandwidth management scheme is implemented in terms of communication protocols. Figure 3 is a diagram showing ~ how many subchannels are allocated within a given radio frequency (RF) channel. Figure 4 is a more detailed block diagram of the elements of a subscriber unit. Figure 5 is a diagram of the state of operations by "a subscriber unit for dynamically requesting and releasing subchannels." Figure 6 is a block diagram of a portion of a base station unit needed to serve each subscriber unit. .

Figure 7 is a high-level structured Spanish description of a process performed by the base station to manage the bandwidth dynamically according to the invention.

DETAILED DESCRIPTION OF THE INVENTION Turning now to the drawings in a more particular way, Figure 1 is a block diagram of a system 100 for providing high speed voice and data service over a wireless connection by continuously integrating such a digital data protocol such as, for example, Integrated Services Digital Networks (ISDN) with a digitally modulated wireless service such as Code Division Multiple Access (CDMA). The system 100 consists of two different types of components, including the subscriber units 101, 102 and the base stations 170. Both types of these components 101 and 170 operate to provide the necessary functions in order to achieve the desired implementation of the system. the invention. The subscriber unit 101 provides wireless data services to a portable computer device 110, such as a portable laptop, portable computer, personal digital assistant (PDA) or the like. The base station 170 cooperates with the subscriber unit 101 to allow data transmission between the portable computer device 110 and other devices, such as those connected to the Public Switched Telephone Network (PSTN) 180. More particularly, the services of Voice and / or data are also provided by the subscriber unit 101 to the portable computer 110 as well as to one or more other devices, such as telephones 112-1, 112-2 (collectively referred to herein as telephones 112). (Telephones 112 can connect themselves, in turn, to other modems and computers that are not shown in Figure 1). In the usual ISDN language, the portable computer 110 and telephones 112 are referred to as terminal equipment (TE). The subscriber unit 101 provides the functions referred to as a network termination type 1 (NT-1). The illustrated subscriber unit 101 is intended in particular to operate with a so-called basic rate inferred-type ISDN connection (BRI) which provides two carriers or "B" channels and an individual data channel or "D" channel with the designation usual that is 2B + D. The subscriber unit 101 itself consists of an ISDN modem 120, a device referred to herein as the protocol converter 130 which performs the various functions according to the invention, including interference 132 and bandwidth management 134, a transceiver CDMA 140, and a subscriber unit antenna 150. Various components of the subscriber unit 101 can be realized in discrete devices or as an integrated unit. For example, an existing conventional ISDN modem 120, such as that which is readily available from any number of manufacturers, can be used in conjunction with existing CDMA transceivers 140. In this case, the unique functions are fully provided by the protocol converter 130. that can be sold as a separate device. Alternatively, the ISDN modem 120, the protocol converter 130, and the CDMA transceiver 140 can be integrated as a complete unit and sold as an individual subscriber unit device 101. The ISDN 120 modem converts data and voice signals between the equipment terminal 110 and 112 in the format required by the standard "U" ISDN. The inferred U is a reference point in ISDN systems that designates a point of the connection between the termination of the network (NT) and the telephone company. The protocol converter 130 performs the interference 132 and the functions of the basic bandwidth management 134, which will be described in greater detail below. In general, the interference 132 is to ensure that the subscriber unit 101 appears in the terminal equipment 110, 112 that is connected to the public switched telephone network 180 on the other side of the base station 170 at all times. The bandwidth management function 134 is responsible for assigning and unassigning CDMA radio channels 160, As required. The bandwidth management also includes the dynamic management of the bandwidth allocated to a given session by dynamically assigning sub-portions of the CDMA channels 160 in a manner that is described more fully below. The CDMA transceiver 140 accepts the data from the protocol converter 130 and reforms this data appropriately for transmission through a subscriber unit antenna 150 over CDMA radio link 160-1. The CDMA transceiver 140 can operate on a single individual MHZ 1.25 radio frequency channel or, alternatively, in a preferred embodiment, it can be tuneable on multiple assignable radio frequency channels. The transmissions of the CDMA signals are then received at the base station and processed by the equipment of the base station 170. The equipment of the base station 170 typically consists of multi-channel antennas 171, multiple CDMA transceivers 172, and a bandwidth management functionality 174. Bandwidth management controls the allocation of CDMA 160 radio channels and subchannels. The base station 170 then couples the demodulated radio signals to the Public Switched Telephone Network (PSTN) 180 in a manner that is well known in the art. For example, the base station 170 may communicate with the PSTN 180 over any number of different efficient communication protocols such as primary rate ISDN, or other LAPD-based protocols such as IS-634 or V5.2. It should also be understood that the data signals are bi-directionally moved through the CDMA radio channels 160, i.e., that the data signals originating from the portable computer 110 are coupled to the PSTN 180, and the data signals received from the the PSTN 180 is coupled to the laptop 110. Other types of subscriber units, such as the unit 102, can be used to provide higher speed data services. Such subscriber units 102 typically provide a service referred to as nB + D type service which may use a so-called Primary Rate Inferred (PRI) type protocol to communicate with terminal equipment 110, 112. These units provide a speed service higher such as 512 kbps through an inferia. The operation of the protocol converter 130 and the CDMA transceiver 140 are similar for the subscriber unit of type nB + D 102 as previously described for the subscriber unit 101, with the understanding that the number of radio links 160 that supports the subscriber unit 102 are larger in number or each one has a larger bandwidth. Turning now to Figure 2, the invention can be described in the context of a multilayer protocol diagram of Open Systems Interconnection. The three protocol stacks 220, 230, and 240 are for the ISDN 120 modem, the protocol converter 130, and the base station 170, respectively. The protocol stack 220 used by the ISDN 120 modem is conventional for ISDN communications and includes, on the terminal equipment side, the analog-to-digital conversion (and digital-analog conversion) 221 and the digital data formatting 222 in one layer, and an application layer 223 in layer two. On the side of the inferred U, protocol functions include the Basic Rate Inferred (BRI) as per the standard 1,430 in layer one, a LAPD protocol stacking in layer two, as specified by the Q.921 standard, and higher-level network layer protocols such as Q.931 or X.227 and high-end signaling 228 from end-user to end-user required to establish network-level sessions between modes . The lower layers of the protocol stack 220 add two carrier channels (B) to achieve an individual data rate of 128 kilobits per second (kbps) in a manner that is well known in the art. Similar functionality can be provided in a primary speed inferiase, as used by the subscriber unit 102, to add multiple B-channels to achieve up to a data rate of 512 kbps during the inferred U. The protocol stack 230 associated with the protocol converter 130 consists of a speed inferiase. basic layer one 231 and a LAPD layer two 232 inferred on the side of the inferium U, to join the corresponding layers of the ISDN 220 stacking. At the next higher layer, usually referred to as the network layer, a bandwidth management functionality 235 extends both on the underside U side and the CDMA radio link side of the protocol converter stack 230. On the CDMA 160 radio link side, the protocol depends on the type of CDMA radio communication in use. An efficient wireless protocol referred to herein as EW [x] 234, encapsulates the ISDN protocol stacks of layer one 231 and layer two 232, such that terminal equipment 110 can be disconnected from one or more CDMA radio channels without interrupt a session of the highest network layer ... The base station 170 contains the union of the CDMA 241 and EW [x] 242 protocols as well as the bandwidth management 243. On the PSTN side, the protocols may be converted back to the basic speed 244 and LAPD 245 or may also include higher-level network layer protocols such as Q.931 or V5.2 246. The call processing functionality 247 allows the Network layer establish and interrupt the channels and provide other processing required to support end user to end user session connections between the nodes as is known in the art. The interference function 132 performed by the EW [x] 234 protocol includes the functions necessary to maintain the U inferrence for the adequately maintained ISDN connection, even in the absence of the availability of a CDMA 160 radio link. This is necessary because ISDN, which is a protocol originally developed for cable line connections, envisages sending a continuous stream of synchronous data bits regardless of whether the terminal equipment at either end actually has data to transmit. Without the interference function 132, radio links 160 of sufficient bandwidth would be required to support at least one data rate of 192 kbps during the entire time of an end-to-end network layer session, whether or not they are not really present the data. EW [x] 234 therefore implies that the CDMA transceiver 140 has to retrace these synchronous data bits over the ISDN communication to interfere with the terminal equipment 110, 112 in the belief that a communication link is continuously available without sufficiently wide threads 160. However, only when data is actually present from the terminal equipment to the wireless transceiver 140 is wireless bandwidth assigned. Therefore, unlike the prior art, the network layer does not need to allocate the assigned wireless bandwidth for the entire communication session. That is, when no data is presented about the terminal equipment to the network equipment, the bandwidth management function 235 initially allocates the allocated radio channel bandwidth 160 and makes it available to another transceiver and another subscriber unit 101. In order to better understand how the management of the width of the band 235 and 243 achieves dynamic allocation of the radio band width, attention is now turned to Figure 3. This figure illustrates a possible plane of frequencies for the wireless links 160 according to the invention. In particular, a typical transceiver 170 can be tuned through command to any channel -1.25 MHZ within a much larger bandwidth, such as up to 30 MHZ. In the case of location in existing cellular radio frequency bands, these bandwidths are typically made available in the range from 800 to 900 MHZ. For wireless systems of personal communication systems (PCS) type, the bandwidth is typically allocated in the range from about 1.8 to 2.0 GigaHertz (GHz). Additionally, there are typically two active bonding bands simultaneously, separated by a protection band, such as 80 MHz; the two binding bands form direct and reverse complete double bonds. Each of the CDMA transceivers, such as the transceiver 140 in the subscriber unit 101 and the transceivers 172 in the base station 170, are capable of being tuned at any given point in time to a radio frequency channel 1, 25 MHZ given. It is generally understood that such a 1.25 MHZ radio frequency carrier provides, at most, a maximum total data rate transmission equivalent of approximately 500 to 600 kbps within acceptable bit error rate limitations. In the prior art, it was therefore generally understood that in order to support an ISDN-type connection that can contain information at a rate of 128 kbps, at most, only subscriber units of about (500 kbps) could be supported. / 128 kbps) or only 3 ISDN. Contrary to this, the present invention subdivides the available bandwidth of 500 to 600 kbps into a relatively large number of subchannels. In the illustrated example, the bandwidth is divided into 64 subchannels 300, each providing a data rate of 8 kbps. A given subchannel 300 is physically implemented by encoding a transmission with a number of different assignable pseudorandom codes. For example, the 64 subchannels 300 can be defined within a single CDMA RF carrier using different orthogonal Walsh codes for each defined subchannel 300. The basic idea underlying the invention is to allocate subchannels 300 only when necessary. For example, multiple subchannels 300 are granted during instants in which a particular ISDN subscriber unit 102 is requiring large amounts of data to be transferred. These subchannels 300 are released during the instants in which the subscriber unit 101 is relatively lightly loaded. Before describing how subchannels are preferably assigned and de-allocated, it will help to understand the description of a typical subscriber unit 101 in greater detail. Turning now to Figure 4, it can be seen that an exemplary protocol converter 130 consists of a microcontroller 410, a reverse link processing 420, and a forward link processing 430. The reverse link processing 420 further includes a device of ISDN 422 reverse interference, a speech data detector 423, a speech decoder 424, a data manipulator 426, and a channel multiplexer 428. The forward link processing 430 contains analogous functions operating in the reverse direction, including a channel multiplexer 438, a voice data detector 433, a speech decoder 434, a data manipulator 436, and a front interference device ISDN 432. In operation, the reverse link 420 first accepts the channel data from the modem ISDN 120 over the inferium U and forward them to the ISDN 432 reverse interference device. The repetitive, redundant "echo" bits are they limit the received data and, once extracted, they are sent to the direct interference device 432. The remaining layer three and the highest level bits are, therefore, the information that needs to be sent over a wireless link. This extracted data is sent to the speech decoder 424 or to the data manipulator 426, depending on the type of data being processed. Any of the D-channel data from the ISDN modem 120 is sent directly to the voice data detection 423 for insertion into the D-channel inputs to the channel multiplexer 428. The voice data detection circuit 423 determines the content of the D channels by analyzing the commands received in the D channel. The commands of the D channel can also be interpreted to control a class of wireless services provided. For example, the controller 410 can store a customer parameter table that contains information about the desired service class of the clients., which may include parameters such as maximum data rate and the like. The appropriate commands are, therefore, sent to the channel multiplexer 428 to request one or more required subchannels 300 on the radio links 160 for communication. Then, depending on whether the information is voice or data, either the speech decoder 424 or the data manipulator 426 begin to feed the data inputs to the channel multiplexer 428. The channel multiplexer 428 can make additional use of the signals of control provided by the voice data detection circuits 423, depending on whether the information is voice or data. Additionally, the CPU 410 controller, which operates in connection with the channel multiplexer 428, contributes to providing the necessary implementation of the EW [x] 234 protocol between the subscriber unit 101 and the base station 170. For example, the subchannels, the establishment of the channel, and the channel interruption commands are sent through commands placed in the wireless control channel 440. These commands are intercepted by the equivalent functionality in the base station 170 to cause the proper allocation of subchannels 300 to the sessions of the particular network layer. The data manipulator 426 provides an estimate of the data rate required for the controller of the CPU 410 so that appropriate commands can be sent on the control channel 440 to assign an appropriate number of subchannels. The data manipulator 426 may also perform a set of packets and a temporary storage of the three layer data in the appropriate fashion for transmission. The direct link 430 works analogously. In particular, the signals are first received from the channels 160 by the channel multiplexer 438. In response to the reception information in the control channels 440, the control information is routed to the voice data detection circuit 433. After from the determination that the received information contains data, the received bits are routed to the data manipulator 436. Alternatively, the information is voice information, and is routed to the speech decoder 434. The data and voice information is then sent to the ISDN 432 direct interference device for construction in an appropriate ISDN protocol format. This set of information is coordinated with the reception of echo bits from the ISDN inverse interference device 422 to maintain the appropriate expected synchronization in the U-inferred with the ISDN 120 modem. It can now be seen how a communication session of the layer of the The network can be maintained even when the width of the wireless band initially assigned for transmission is reassigned to other uses when there is no information to be transmitted. In particular, the reverse interference devices 422 and direct 432 cooperate to retrace the loop of signals that do not carry information, such as indicator patterns, sync bits, and other necessary information, to interfere with the data terminal equipment connected to the ISDN modem. 120 which continues to operate as long as the wireless path assigned over the CDMA 150 transceiver is continuously available. Therefore, unless there is a real need to transmit the information from the terminal equipment that must be presented to the channel multiplexers 428, or that actual information is being received from the channel multiplexers 438, the invention can initially deallocate the sub-channel assigned 300, thereby making it available to another subscriber unit 101 of the wireless system 100. The CPU410 controller can also perform additional functions to implement the EW [x] 234 protocol, including error correction, storage temporary packages, and the measurement of percentages of binary errors. The functions necessary to implement the bandwidth management 235 in the subscriber unit 101 are performed in combination with the EW [x] protocol typically by the CPU 410 controller operating in cooperation with the channel multiplexers 428, 438, and the data manipulators 420, 436. In general, the bandwidth allocations are made for each session of the network layer based on the data rate needs of short duration measured. One or more subchannels 300 are assigned based on these measurements and other parameters such as the amount of data that is in the queue or the priority of the service that is assigned by the service provider. Additionally, when a given session is inactive, an end user to end user connection is still preferably maintained, albeit with a minimum number of assigned sub-channels, such as an individual sub-channel. For example, this individual subchannel may eventually be removed after a predetermined minimum idle time is observed. Figure 5 is a detailed view of the process by which a subscriber unit 101 can request subchannel assignments 300 from the base station 170 according to the invention. In a first state 502, the process is in an inactive state. At some point, the data is ready to be transmitted and the state 504 is entered, where the fact that the data is ready to be transmitted can be detected by a data entry buffer in the data manipulator 426 indicating that the data is ready . In state 504, a request is made, such as through a control channel 440, for the assignment of a sub-channel to the subscriber unit 101. If a sub-channel is not immediately available, a regulation state 506 can be introduced, wherein the subscriber unit simply waits and queues his request to be assigned a subchannel. Eventually, a subchannel 300 is granted by the base station and the process goes to state 508. In this state, the data transfer can then begin using the assigned individual sub-channel. The process will continue in this state as long as the individual sub-channel 300 is sufficient to maintain the data transfer required and / or is being used. However, if the input buffer is empty, as reported by the data manipulator 426, then the process will go to a state 510. In this state 510, the subchannel will remain assigned in case it is resumed again the data traffic. In this case, such as when the input buffer begins to be filled again and the data is again ready to be transmitted, then the process returns to state 508. However, if from the 510 state a low traffic clock expires, then the process goes to state 512 in which the individual sub-channel 300 is released. The process then returns to the inactive process 502. In state 512, if a queue request is pending from states 506 and 516, the sub-channel is used for satisfy such a request instead of releasing it. Returning to state 508, if, instead, the content of the input buffer is beginning to fill at a rate exceeding a predetermined threshold indicating that subchannel 300 is insufficient to maintain the necessary data flow, then it is introduced a state 514 in which more subchannels 300 are required. A subchannel request message is sent again on the control channel 440 or through an already assigned subchannel 300. If the additional sub-channels 300 are not immediately available, then a regulation status can be entered and the request can be attempted again by returning to state 514 and 516, as required. Eventually, an addition subchannel will be granted and the processing may return to state 508. With the additional subchannels now available, the processing goes to state 518, where the data transfer can be performed on a multiple N of the subchannels. This can be done at the same time through a channel binding function or other mechanism to allocate the input data between the N subchannels. As the contents of the input buffer are reduced below an empty threshold, then a wait state 520 may be entered. However, if a buffer filling speed is exceeded, then state 514 may be entered, whereby again more sub-channels 300 are required. In state 520, if a High traffic clock has expired, then one or more of the additional subchannels are released in state 522 and the process returns to state 508. Figure 6 is a block diagram of the equipment components of base station 170 of the system 100. These components perform analogous functions with respect to those already described in detail in Figure 4 for the subscriber unit 101. It should be understood that a direct link 620 and a reverse link 630 are required for each subscriber unit 101 and 102, which must be supported by the base station 170. The base station direct link 620 operates analogously with respect to the reverse link 420 in the subscriber unit 100, including a reverse multiplexer 6 22 of sub-channel, the voice data detection, the speech decoder 624, the data manipulator 626, and the ISDN interference device 622, with the understanding that the data travels in the opposite direction in the base station 170 Similarly, the reverse link 630 of the base station includes components analogous to those described in the direct link of the subscriber 430, which includes an ISDN deinterference device 632, voice data detection 633, speech decoder 634, data manipulator 636, and subchannel multiplexer 638. The base station 170 also requires a CPU controller 610. A difference between the operation of the base station 170 and the subscriber unit 101 is in the implementation of the management functionality of the width of the band 243. This can be implemented in the CPU controller 610 or in another process in the base station 170. A high level description of a software process performed by the r the channel dynamic allocation portion 650 of the bandwidth management 243 is contained in Figure 7. This process includes a main program 710, which is executed continuously, and includes requests for processing ports, release of the width of the processing base band, bandwidth requests, and then location and interruption of unused subchannels. The processing of port requests is more detailed particularly in a code module 720. These include receiving a port request, and reserving a sub-channel for the new connection, preferably chosen from the least used section of the bandwidth of the port. radio frequency. Once the reservation is made, an RF channel code and frequency assignment is returned to the subscriber unit 101 and a table of subchannel assignments is updated. Otherwise, if the subchannels are not available, then the port request is added to a port request queue. An expected timeout can be estimated in accordance with the number of priorities and pending port requests, and an appropriate wait message can be returned to the requesting subscriber unit 101. In a band width releasing module 730, it is notifies the binding function of the channel running in multiplexer 622 in the direct link the need to release a sub-channel. The frequency and code are returned to an available subchannel group and a radio record is updated. The next request module for the bandwidth 740 may include selecting the request that has the highest priority with the use of the lowest bandwidth. Next, a list of available subchannels is analyzed to determine the maximum available number. Finally, subchannels are assigned based on need, priority, and availability. A function of joining the width of the channel band is reported within the multiplexer of the sub-channel 622 and the radio register that maintains the sub-channels that are assigned to the respective connections is updated. In the bandwidth demand algorithm, probability theory can typically be used to manage the number of available connections or ports, and the spectrum needed to maintain the expected overall size and frequency of subchannel assignments. There may be provisions for priority service based on subscribers who have paid a fee for their services. It should be understood, for example, that in the case of a 128 kbps ISDN subscriber unit can be allocated in a given time even more than 16 x 8 kbps subchannels. In particular, a larger number, such as 20 subchannels, may be allowed to compensate for the delay and reaction in the assignment of subchannels. This also allows dealing with bursts of data in a more efficient manner as typically experienced during the loading of Web pages. Additionally, voice traffic can be prioritized in relation to data traffic. For example, if a voice call is detected, at least one sub-channel 300 can be activated at all times and assigned exclusively to the voice transfer. In this way, the probability of blocking voice calls will be decreased.

EQUIVALENTS Although the invention has been particularly shown and described with references to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details thereof may be made without departing from the spirit and scope of the invention. invention, as defined by the appended claims. For example, instead of ISDN, other digital cable line protocols can be encapsulated by the EW [x] protocol, such as xDSL, Ethernet, and X.25, and therefore the dynamic subchannel allocation scheme can be advantageously used. wireless described here. Those skilled in the art will recognize or be able to know, using only routine experimentation, many equivalents with respect to the specific embodiments of the invention specifically described herein. Such equivalents are intended to be included in the scope of the claims.

Claims (10)

Claims

1. A method for providing wireless communication of digital signals, the digital signals being communicated between a plurality of wireless subscriber units and a base station, the digital signals being communicated using at least one radio frequency channel through radio signals. modulated Radio Code Division Multiple Access (CDMA), the digital signals also having a given nominal data rate, the method comprising the steps of: a) making available a plurality of subchannels within each CDMA radio channel, where the data rate of each subchannel is much smaller than the nominal data rate of the digital signals; b) establishing a session of the network layer between the terminal equipment connected to the subscriber unit through the base station to another terminal equipment connected to the base station; and c) during the network layer session, allocate available subchannels only on a basis as needed, the number of assigned subchannels being changed thus changing during the period of a given session.

2. A method according to claim 1, wherein a plurality of subchannels are made available on an individual radio frequency carrier by assigning orthogonal codes for each subchannel.

A method according to claim 1, wherein step b) further comprises: i) after establishing a session of the network layer, initially assign an individual sub-channel; and ii) when a session requires additional bandwidth to maintain the transmission of the digital signals, assign additional subchannels.

4. A method according to claim 1, wherein the digital signals include a digitized representation of a speech signal, further comprising the step of: maintaining the allocation of sub-channels sufficient to meet the requirements of the bandwidth of the signal of voice during the connection time of the session.

5. A method according to claim 1, wherein the digital signals include a digitized representation of a speech signal, further comprising the step of: selecting a sub-channel bandwidth to be sufficient to transmit the signal bandwidth of voice continuously.

6. A method according to claim 1, wherein step c) further comprises: when no digital signals are present during the connection of the session, unassign the subchannels while maintaining the connection of the session in the network layer and interfere at the same time the lower physical layers in the subscriber unit behave as if sufficient bandwidth is available to continuously transmit digital signals.

7. A method according to claim 1, wherein the subchannels are allocated over a service base priority class among a number of subscriber units.

8. A method according to claim 1, wherein the digital signals are of different nominal bandwidths.

9. A method according to claim 1, wherein step (a) of making available a plurality of subchannels within each CDMA radio channel further comprises assigning multiple orthogonal codes to each CDMA channel to thereby provide multiple subchannels, supporting each subchannel only a data rate that is much lower than the data rate supported by the CDMA channel itself.

10. A method according to claim 1, further comprising the steps of: d) temporarily store the data received from the terminal equipment session until there is a minimum number of data elements that need transmission; e) requesting (504) at least one subchannel assignment for the terminal equipment session; f) transmit (508) data using the assigned subchannels; g) after a number of data elements stored in the buffer exceed a predetermined maximum threshold amount, request (514) that additional subchannels be assigned to communications from the terminal equipment session; and after a number of data elements buffered fall below a predetermined minimum threshold amount, release (522) the sub-channels of the assignment to the terminal equipment session.