JP2007043728A - Dynamic bandwidth allocation for transmitting wireless protocol across code division multiple access (cdma) radio link - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-rate data and voice service on wireless connection by integrating a digital data protocol, without joints over a digital modulation wireless service of code division multiple access (CDMA) or the like. <P>SOLUTION: Bandwidth is allocated dynamically within a session to a specific CDMA subscriber unit, based on the data rate determinations. In particular, a dynamic bandwidth allocation algorithm operates from allowable limits calculated, based on the available ports per subscriber, expected user bandwidth, and parallel user bandwidth versus throughput. Functions for priority service, imbalanced forward and reverse spectrum utilization, voice prioritization and band switching are also provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The increasing use of wireless telephones and personal computers by the general public has led to a demand for advanced communications services that were previously thought to be used only for specific applications.

  For example, in the late 1980s, wireless voice communication, which is effective for cellular telephones, was a business privilege due to high subscription fees. The same was true when accessing a distant computer network. Therefore, until recently, computers and communication line access devices that only business people and large institutions needed could be purchased.

  Today, however, the general public is increasingly wanting not only access to networks such as the Internet and private intranets, but to access wireless networks as well. This is particularly important for users of portable computers, laptop computers, handheld personal information terminal devices and the like. These users would rather access the network without connecting to a telephone line.

  There are still no widespread satisfactory solutions that can use existing wireless networks to access the Internet and other networks at low cost and high speed. This situation is none other than the product of an adverse environment. For example, the common method of providing high-speed data services in a business environment over a wired network is not easily adaptable to voice-grade services available in most homes and offices. Furthermore, such standard high-speed data services are not suitable for efficient transmission with standard cellular systems and wireless transceivers.

  Furthermore, existing cellular networks were originally designed only for voice service delivery. Even today, the wireless modulation schemes used are focused on delivering voice information at the maximum data rate only within the easily available 9.6kbps range. This is because most countries' cellular switching networks, including the United States, use analog voice channels with bandwidths of about 300 to 3600 HZ. Such low frequency channels do not lend themselves to transmitting data directly, even at a rate of 28.8 kbps (kilobits per second) or even at a rate of 56.6 kbps, which is now generally available using low cost wired modems. Such a speed is now considered the minimum allowable data transfer rate for Internet access.

  Currently in the United States, high-speed block assembly switching networks have been used. A specific wired network called ISDN (Integrated Services Digital Network), which allows high-speed data access, has been known for many years, but the charges have only recently been reduced, even for wired services in general homes The price has become attractive to users. Most of these networks were known at the time the cellular system was first developed, but are not ready to provide data services on the order of ISDN over cellular network topologies.

  ISDN is essentially a circuit switching protocol designed to synchronize between terminal nodes by continuously transmitting bits while maintaining a connection. The disadvantage is that in a wireless environment, access to channels is expensive and there is competition for them. Communication media is expected to be inherently sharable. This is different from a normal wired ISDN environment that is essentially not intended for line sharing.

  The present invention uniquely integrates the ISDN protocol with existing cellular signals that can utilize code division multiple access (CDMA) type modulation systems to provide high-speed data and voice services over standard wireless connections. It is to provide. The present invention achieves a high data transfer rate by more efficiently allocating access to the CDMA wireless channel. Specifically, a number of subchannels are defined within the standard CDMA channel bandwidth, for example by specifying separate codes, and these subchannels are typically required to support the ISDN protocol. The instantaneous bandwidth required by each online subscriber unit is accommodated by dynamically assigning multiple subchannels of RF (radio frequency) carriers to each session as needed. For example, a plurality of subchannels may be allowed during a period of relatively high subscriber bandwidth requirements, such as when a web page is downloaded, and a web page previously downloaded by the subscriber. The line is released during periods of relatively light loads, such as when reading or performing other tasks.

  The subchannel assignment algorithm can be implemented to provide various levels of priority service to a particular subscriber. These algorithms are specified based on available ports per subscriber, expected user bandwidth, service surcharge, etc.

  According to another aspect of the invention, a portion of the available bandwidth is initially allocated to establish a communication session. Once the session is established, if there is no data to be transmitted to the subscriber unit, that is, if the data path is stationary for a certain length of time, the previously specified bandwidth allocation is de-allocated. Furthermore, it is preferable to keep at least a certain portion available to the subscribers in the session, rather than deallocating all previously allocated bandwidth allocations. If the quiescent state continues for a longer time, even the remainder of the bandwidth is deallocated from the session. The logical session connection of the network layer protocol is maintained as it is even when no subchannel is specified.

  In a preferred configuration, a single subchannel is maintained for each network layer connection for a predetermined minimum idle time. This helps to efficiently manage channel setup and release.

  The above and other objects, features and advantages of the present invention will become apparent from the following description of preferred embodiments with reference to the drawings. In the accompanying drawings, the same reference numerals are used for the same parts throughout the different drawings.

  The drawings will be described more specifically. FIG. 1 is a block diagram of a system 100 that seamlessly integrates a digital data protocol such as ISDN with a digital modulation wireless service such as code division multiple access (CDMA) to provide a wireless connection. Provide high-speed data and voice services above.

  The system 100 consists of two types of components and includes subscriber units 101 and 102 and a base station 170. Both types of these elements 101 and 170 work together to provide the necessary functions and implement the present invention as desired. Subscriber device 101 provides wireless data services to portable computing device 110, such as a laptop computer, portable computer, personal digital assistant (PDA), and the like. Base station 170 cooperates with subscriber device 101 to allow data transmission between portable computer device 110 and other devices such as those connected to public switched telephone network (PSTN) 180.

  More specifically, the subscriber device 101 allows data and / or voice services such as telephones 112-1 and 112-2 (hereinafter collectively referred to as telephones 112) in addition to the portable computer 110. Also provided for one or more devices. (The telephone 112 itself may also be connected to other modems and computers not shown in FIG. 1). In normal ISDN terminology, portable computer 110 and telephone 112 are called terminal equipment (TE). Subscriber apparatus 101 provides a function called network terminal type 1 (NT-1). The illustrated subscriber unit 101 operates in particular with a so-called basic rate interface (BRI) type ISDN connection and provides two transports or B channels and one data or D channel (usually represented as 2B + D).

  Subscriber device 101 itself is referred to as ISDN modem 120, herein as protocol converter 130, a device that performs various functions according to the present invention, including spoofing 132 and bandwidth management 134, CDMA transceiver 140, It consists of a subscriber unit antenna 150. Various components of the subscriber device 101 are realized as separate devices or integrated devices. For example, an existing customary ISDN modem 120 sold by many manufacturers can be used in combination with an existing CDMA transceiver 140. In this case, the entire unique function is provided by the protocol conversion device 130 sold as a separate device. On the other hand, the ISDN modem 120, the protocol conversion device 130, and the CDMA transceiver 140 are integrated as a complete device and can be sold as a single subscriber device 101.

  The ISDN modem 120 converts data and audio signals between the terminal devices 110 and 112 into a format required by the standard ISDN “U” interface. The U interface is a reference point of the ISDN system and designates a connection point between the network terminal (NT) and the telephone company.

  The protocol converter 130 performs spoofing 132 and basic bandwidth management 134 functions and will be described in more detail later. In general, the spoofing 132 ensures that the subscriber unit 101 is shown to the terminal units 110 and 112 as if they are always connected to the public switched telephone network 180 on the opposite side of the base station 170. is there.

  The bandwidth management function 134 performs allocation and deallocation of the CDMA radio channel 160 as necessary. Bandwidth management also includes a function of dynamically specifying a sub-part of the CDMA channel 160 and dynamically managing the bandwidth allocated to a given session. This method will be described in detail later.

  The CDMA transceiver 140 receives data from the protocol converter 130 and reformats the data into a form suitable for transmission over the CDMA radio link 160-1 through the subscriber equipment antenna 150. The CDMA transceiver 140 may operate with only a single 1.25 MHz radio frequency channel or may tune to multiple assigned radio frequency channels in another preferred embodiment.

  The CDMA signal transmission is received at the base station and processed by the base station apparatus 170. The base station apparatus 170 is generally composed of a multi-channel antenna 171, a multiple CDMA transceiver 172, and a bandwidth management function 174. Bandwidth management controls the allocation of CDMA radio channel 160 and subchannels. Next, base station 170 couples the demodulated radio signal to public switched telephone network (PSTN) 180 using a conventionally known method. For example, base station 170 can communicate with PSTN 180 via a number of different efficient communication protocols, such as primary group rate ISDN, or other LAPD-based protocols (such as IS-634 and V5.2).

  It will be appreciated that data signals are transmitted bi-directionally over the CDMA radio channel 160. That is, a data signal generated by portable computer 110 is coupled to PSTN 180, and a data signal received from PSTN 180 is coupled to portable computer 110.

  Other types of subscriber devices, such as device 102, can be used to provide faster data services. Such a device 102 provides a service that is usually called an nB + D type. This service can communicate with the terminal devices 110, 112 using a protocol called Primary Group Rate Interface (PRI) type protocol. These devices provide higher speed services such as 512 kbps on the U interface. The operations of the protocol conversion device 130 and the CDMA transceiver 140 are the same as those of the subscriber device 101 described above for the nB + D type subscriber device 102. However, it will be appreciated that there are a greater number of wireless links 160 supporting subscriber unit 102, or each having a wider bandwidth.

  Next, FIG. 2 will be described. The present invention can be described in the context of an Open Systems Interconnection (OSI) multilayered protocol diagram. The three protocol stacks 220, 230, and 240 are for the ISDN modem 120, the protocol converter 130, and the base station 170, respectively.

  A protocol stack 220 used in the ISDN modem 120 is usually provided for ISDN communication. The protocol stack 220 has analog-digital conversion (and digital-analog conversion) 221 and digital data formatting 222 in the first layer and an application layer 223 in the second layer on the terminal device side. On the U interface side, the protocol functions are the basic rate interface (BRI) according to standard 1.430 in the first layer and the standard Q.2 in the second layer. LAPD protocol stack specified in 921, required to establish a network level session between modes, Q. 931 or X.I. 227 as well as higher level network layer protocols such as higher level end-to-end signal 228.

  The lower layer of the protocol stack 220 realizes a single data transfer rate of 128 kbps by combining two carrier (B) channels in a known manner. A function similar to that used in the subscriber unit 102 is provided by the primary group rate interface, and a data transfer rate of up to 512 kbps can be realized via the U interface by integrating multiple B channels. Yes.

  The protocol stack 230 incorporated in the protocol converter 130 is composed of a first layer basic speed interface 231 and a second layer LAPD interface 232 on the U interface side, and matches the corresponding layer of the ISDN modem stack 220. To do.

  In the next higher layer, usually referred to as the network layer, bandwidth management 235 spans both the U interface side and the CDMA radio link side of the protocol converter stack 230. On the CDMA radio link side 160, the protocol depends on the CDMA radio communication method used. An efficient wireless protocol, referred to herein as EW [x] 234, encapsulates the first layer 231 and second layer 232 ISDN protocol stacks and provides one terminal device 110 without interrupting higher network layer sessions. Separated from the above CDMA radio channels.

  The base station 170 has a bandwidth management 243 in addition to the CDMA 241 and EW [x] 242 matching protocols. On the PSTN side, the protocol may convert back to the basic rate interface 244 and LAPD 245, or It may have a higher level network layer protocol such as 931 or V5.2246.

  Call processing function 247 allows the network layer to set up and release channels, and also provide other processing required to support end-to-end session connections between previously known nodes.

  The spoofing function 132 performed by the EW [x] protocol 234 has the functions necessary to properly maintain the U interface for ISDN connections even when no CDMA radio link 160 is available. This function is necessary because ISDN was originally developed for wired connections, so that regardless of whether one of the terminal devices actually has transmission data, This is because a stream is predicted to be transmitted. Without the spoofing function 132, a radio link 160 with sufficient bandwidth to support a data rate of at least 192 kbps, during the duration of an end-to-end network layer session, with or without actual data present Is needed.

  Therefore, if the EW [x] 234 loops back these synchronous data bits to the CDMA transceiver 140 on the ISDN communication path and continuously uses the sufficiently wide wireless communication link 160, the EW [x] 234 Make me believe. However, wireless bandwidth is allocated only when data is actually delivered from the terminal device to the wireless transceiver 140. Thus, unlike the prior art, the network layer does not need to allocate a specified wireless bandwidth for the entire communication session. In other words, if data is not provided from the terminal device to the network device, the bandwidth management function 235 deallocates the radio channel bandwidth 160 that was initially specified, and transmits it to another transceiver and another subscriber device. 101 can be used.

  With reference to FIG. 3, it can be seen how bandwidth management 235 and 243 implements dynamic allocation of radio bandwidth. This figure shows one possible frequency scheme for a radio link 160 according to the present invention. Specifically, the regular transceiver 170 is tuned to command for any 1.25 MHz channel within a very wide bandwidth, such as up to 30 MHz. For frequency settings within existing cellular radio frequency bands, these bandwidths are typically available in the range of 800 to 900 MHz. In personal communication equipment (PCS) type wireless devices, bandwidth is typically allocated in the range of about 1.8 to 2.0 GHz. Furthermore, generally, two matching bands that are separated by a guard band such as 80 MHz operate simultaneously. The two matching bands form a forward and reverse full duplex link.

  Each of the CDMA transceivers, such as transceiver 140 in subscriber unit 101 and transceiver 172 in base station 170, can be tuned to a predetermined 1.25 MHz radio frequency channel at any time point. Such a 1.25 MHz radio frequency carrier is generally understood to be about 500 to 600 kbps maximum data rate transmission as a whole, at best, within acceptable bit error rate limits.

  In the prior art, in general, only about (500 kbps / 128 kbps) or three ISDN subscriber devices can support at best, to support ISDN-like connections with speed information of 128 kbps. Understood.

  In contrast, the present invention further divides the available bandwidth of about 500 to 600 kbps into a relatively large number of subchannels. In the illustrated example, the bandwidth is divided into 64 subchannels 300, each having a data rate of 8 kbps. In a given subchannel 300, the transmission is encoded physically with one of a plurality of different specifiable pseudorandom codes and is physically realized. For example, 64 subchannels 300 can be defined within a single CDMA RF carrier using a separate orthogonal Walsh code for each defined subchannel 300.

  The basic concept of the present invention is to assign subchannel 300 only when needed. For example, multiple subchannels 300 are allowed during a time when a particular ISDN subscriber device 101 is requesting transmission of a large amount of data. These subchannels 300 are opened during a period when the subscriber unit 101 is relatively lightly loaded.

  The preferred method of subchannel allocation and deallocation described above helps to understand the normal subscriber unit 101 in detail. Next, FIG. 4 will be described. An example of the protocol conversion device 130 includes a microcontroller 410, a reverse link processing device 420, and a forward link processing device 430. The reverse link processing device 420 further includes an ISDN reverse spoofer 422, an audio data detection unit 423, an audio decoder 424, a data processing unit 426, and a channel multiplexer 428. The forward link processing device 430 operates in the reverse direction of the reverse link processing device 420 and has a similar function, and includes a channel multiplexer 438, an audio data detection unit 433, an audio decoder 434, a data processing unit 436, and an ISDN forward spoof. It has a face 432.

  In operation, reverse link 420 first receives channel data from ISDN modem 120 via the U interface and sends it to ISDN reverse spoofer 432. With each iteration, redundant “echo” bits are removed from the received data and, once extracted, are sent to the spoofer 432. Thus, the remaining layer 3 and higher level bits are information that needs to be transmitted over the wireless link.

  The extracted data is sent to the audio decoder 424 or the data processing unit 426 depending on the type of data to be processed.

  All D channel data from the ISDN modem 120 is directly sent to the voice data detection unit 423 and input to the D channel input of the channel multiplexer 428. The voice data detection circuit 423 analyzes the command received on the D channel and determines the contents of the D channel.

  D channel commands may be decoded to control the class of wireless service provided. For example, the controller 410 may store a customer parameter table with information about customers who want a service class, including parameters such as maximum data transfer rate. In this way, appropriate commands are sent to the channel multiplexer 428 to request one or more required subchannels 300 on the radio link 160 required for communication. Thereafter, either the audio decoder 424 or the data processing unit 426 starts supplying data input to the channel multiplexer 428 depending on whether the information is audio or data.

  The channel multiplexer 428 uses a control signal provided from the audio data detection circuit 423 depending on whether the information is audio or data.

  Further, the CPU controller 410 operates in conjunction with the channel multiplexer 428 to assist in providing the necessary embodiment of the EW [x] protocol 234 between the subscriber unit 101 and the base station 170. For example, subchannel requests, channel setup, and channel release instructions are sent via commands located on the wireless control channel 440. These commands are intercepted by equivalent functional parts in the base station 170 and appropriately assign the subchannel 300 to a particular network layer session.

  The data processor 426 estimates the required data transfer rate for the CPU controller 410 so that an appropriate command can be sent on the control channel 440 to assign an appropriate number of subchannels. Data processor 426 may also perform packet assembly and buffer the third layer data in an appropriate format for transmission.

  The forward link 430 operates similarly. In particular, the signal is first received from channel 160 by channel multiplexer 438. In response to the information received on the control channel 440, the control information is transferred to the voice data detection circuit 433. If it is determined that the received information includes data, the received bit is transferred to the data processing unit 436. On the other hand, the audio information is transferred to the audio decoder 434.

  The voice and data information is then sent to the ISDN forward spoofer 432 and configured into the appropriate ISDN protocol format. In assembling this information, the echo bits received from the ISDN reverse spoofer 422 are adjusted to maintain accurate synchronization on the U interface with the ISDN modem 120.

  A method is described below for maintaining a network layer communication session even if the wireless bandwidth originally allocated for transmission is reallocated for other uses when there is no information to transmit. Specifically, the reverse spoofer 422 and the forward spoofer 432 cooperate to loop back a carrier signal having no information such as a flag pattern, a synchronization bit, and other necessary information, via the CDMA transceiver 150. It looks like a data terminal device connected to the ISDN modem 120 and continuing to operate as if the assigned wireless path is still available.

  Thus, unless there is an actual need to transmit information from a particular terminal device to channel multiplexer 428 or actual information received from channel multiplexer 438, the present invention deallocates the first designated subchannel 300. As a result, the wireless system 100 can be used for another subscriber device.

  The CPU controller 410 further has additional functions for implementing the EW [x] protocol 234, including error correction, packet buffering, and bit error rate measurement.

  This function is necessary to perform bandwidth management 235 in the subscriber unit 101, and is usually combined with the channel multiplexers 428 and 438 and the data processing units 420 and 436 in combination with the EW [x] protocol. It is executed by the operating CPU controller 410. In general, bandwidth designation is specified for each network layer session based on measured short-term data rate requirements. One or more subchannels 300 are specified based on parameters such as these measurements and the amount of data in the queue, or service priority specified by the service provider. Furthermore, if the predetermined session is idle, it is preferable that the connection is maintained between terminals even in the minimum number of subchannel holding states as in the case where a single subchannel is designated. For example, this single subchannel eventually ends after a predetermined minimum idle time has elapsed.

  FIG. 5 shows details of processing of the subscriber unit 101. The subscriber unit 101 requests the allocation of the subchannel 300 from the base station 170 according to the present invention. In the initial state 502, the process is idle. At some point, the data is ready for transmission and enters state 504. There, the fact that data is ready for transmission is detected by an input data buffer in the data processing unit 426 indicating that the data is ready.

  In state 504, a request is made, for example, via control channel 440 for assigning subchannels to subscriber unit 101. If the subchannel is not immediately available, the pacing state 506 is entered, in which the subscriber unit waits and queues a request for subchannel designation.

  Eventually, subchannel 300 is granted from the base station and processing continues to state 508. In this state, data transfer begins to use a single designated subchannel. As long as a single subchannel 300 is sufficient to maintain the requested data transfer and / or is in use, processing continues in this state. However, when the input buffer is empty, such as when notified by the data processing unit 426, the process proceeds to the processing state 510. In this state 510, when data traffic is resumed, the subchannel remains designated. In this case, the process returns to state 508 when the input buffer is refilled and data can be transmitted again. However, from state 510, if the low traffic timer expires, processing proceeds to state 512 where the single subchannel 300 is released. Thereafter, the process returns to the idle state 502. In state 512, if a queued request remains waiting from state 506 or 516, the subchannel is not released and is used to satisfy the request.

  Returning to state 508, instead, the contents of the input buffer begin to fill at a rate beyond the intended limit, indicating that the single subchannel 300 is insufficient to maintain the required data flow. State 514 is entered and further subchannel 300 is requested. The subchannel request message is sent again on the control channel 440 or through the already assigned subchannel 300. If additional subchannel 300 is not immediately available, the request is retried as necessary by entering pacing state 516 and returning to states 514 and 516. Eventually, additional subchannels are granted and processing can return to state 508.

  Using additional subchannels currently available, processing continues at state 518, where data transfer occurs over N subchannels. This is done simultaneously through channels that combine the function of allocating input data among the N subchannels and other mechanisms. A wait state 520 is entered when the contents of the input buffer decrease below the free limit.

  However, if the buffer fill rate is exceeded, state 514 is entered and subchannel 300 is requested again.

  In state 520, when the high traffic timer expires, one or more additional subchannels are released in state 522 and processing returns to state 508.

  FIG. 6 is a block diagram of components of the base station device 170 of the system 100. These components perform functions similar to those already described in detail for FIG. It will be appreciated that a forward link 620 and a reverse link 630 are required for each subscriber device 101 or 102 that needs to be supported by the base station 170.

  The base station forward link 620 functions in the same manner as the reverse link 420 in the subscriber unit 100, and includes a subchannel demultiplexer 622, an audio data detector 623, an audio decoder 624, a data processor 626, and an ISDN spoofer. However, data is transmitted in the opposite direction through the base station 170. Similarly, the base station reverse link 630 includes elements similar to those in the subscriber equipment forward link 430, including an ISDN spoofer 632, a voice detector 633, a voice decoder 634, a data processor 636, and a subchannel. A multiplexer 638 is included. Base station 170 also requires CPU controller 610.

  One of the differences in operation between the base station 170 and the subscriber unit 101 is an embodiment of the bandwidth management function 243. This is executed by the CPU controller 610 or another process of the base station 170.

  FIG. 7 shows a detailed description of software processing executed by the dynamic channel allocation unit 650 of the bandwidth management 243. This process has a main program 710 that is continuously executed, and includes port request processing, bandwidth release processing, and bandwidth request processing, and searches and releases subchannels that are not being used.

  Port request processing is described in further detail within code module 720. Port request processing reserves a subchannel for a new connection upon receipt of a port request, preferably a subchannel selected from the least utilized section of the radio frequency bandwidth. When the reservation is made, the RF channel frequency and code designation are returned to the subscriber unit 101, and the subchannel allocation table is updated. On the other hand, if the subchannel is not available, the port request is added to the port request queue. The expected waiting time is estimated based on the number of waiting port requests and priority and an appropriate waiting message is returned to the requesting subscriber unit 101.

  The bandwidth release module 730 notifies the channel combining function performed in the multiplexer 622 in the forward link that the subchannel needs to be released. The frequency and code are then returned to the available sub-channel pool and the radio record is updated.

  The next bandwidth request module 740 selects the highest priority request with the minimum bandwidth. Next, the list of available subchannels is analyzed to determine the maximum available number. Finally, subchannels are specified based on necessity, priority, and availability. The channel bandwidth combining function in the subchannel multiplexer 622 is notified and the radio record that records which subchannel is designated for which connection is updated.

  In bandwidth in request algorithms, establishment theory is generally used to manage the number of connections or available ports and the spectrum necessary to maintain the desired throughput size and subchannel frequency designation. In addition, priority services can be provided based on subscribers who pay a premium for services.

  For example, when supporting a 128 kbps ISDN subscriber device 101, it will be understood that more than 16 × 8 kbps subchannels can be allocated at a given time. In particular, a large number of subchannels such as 20 can be assigned to compensate for delay and response in subchannel designation. It can also handle burst data in a more efficient way as commonly experienced while downloading web pages.

  Furthermore, voice traffic can be prioritized over data traffic. For example, when a voice call is detected, at least one subchannel 300 is always active and a voice transfer can be assigned exclusively. In this way, the possibility of disturbing the voice call is minimized.

While the invention has been described in detail with reference to preferred embodiments, those skilled in the art will recognize that various changes can be made in form or detail without departing from the spirit and scope of the invention as defined by the claims. Will be understood.

  For example, instead of ISDN, other wired digital protocols can be used such as xDSL, Ethernet, X. It may be encapsulated with an EW [x] protocol such as 25. This can advantageously use the dynamic wireless subchannel assignment method described here.

  Those skilled in the art will readily be able to conceive and do so without equivalent experiments of the specific embodiments of the present invention described herein, without undue experimentation. Such equivalents are within the scope of the claims.

1 is a block diagram of a wireless communication system using a bandwidth management method according to the present invention. FIG. FIG. 2 is an open system interconnection (OSI) layered protocol diagram, wherein a bandwidth management method is performed by a communication protocol. FIG. 6 illustrates a method for assigning subchannels within a predetermined radio frequency (RF) channel. FIG. 2 is a more detailed block diagram of the components of a subscriber device. FIG. 6 is a state diagram of operations performed by a subscriber unit to dynamically request and release subchannels. It is a block diagram of a part of base station apparatus required in order to serve each subscriber apparatus. FIG. 6 is a highly structured illustration of processing performed at a base station to dynamically manage bandwidth according to the present invention.

Claims (11)

A method for providing wireless communication of digital signals, wherein the digital signals are communicated between a plurality of wireless subscriber units and a base station, the digital signals using at least one radio frequency channel (Code Division Multiple Access). Communicated via a CDMA) modulated radio signal, and the digital signal has a predetermined nominal data rate;
a) making available a plurality of subchannels within each CDMA radio channel, the data transfer rate being slower than the nominal data transfer rate of the digital signal;
b) establishing a network layer session between the terminal device connected to the subscriber device and the other terminal device connected to the base station via the base station;
c) A method for providing wireless communication in which, during the network session, an available subchannel is allocated only when necessary, thereby changing the number of subchannels allocated during the duration of a predetermined session.   The method of claim 1, wherein the plurality of subchannels are made available on a single radio frequency carrier by designating an orthogonal code for each subchannel. The process of claim 1, wherein step b) further comprises:
i) When establishing a network layer session, first assign a single subchannel,
ii) A method for providing wireless communication in which additional subchannels are allocated when a session requires additional bandwidth to maintain the digital signal transmission. 2. The digital signal of claim 1, wherein the digital signal has a digitized representation of an audio signal, and
A method of providing wireless communication that maintains sufficient subchannel allocation to meet the bandwidth requirements of the voice signal during the duration of a session connection. 2. The digital signal of claim 1, wherein the digital signal has a digitized representation of an audio signal, and
A wireless communication providing method of selecting a subchannel bandwidth sufficient to continuously transmit the voice signal bandwidth. The step c) of claim 1, further comprising:
When no digital signal is present during the session connection, the session connection at the network layer is maintained, and the subscriber unit is as if there is sufficient bandwidth available to continuously transmit the digital signal. A method for providing wireless communication in which the subchannel is unassigned while pretending to be the lower physical layer of the network.   2. The method of providing wireless communication according to claim 1, wherein the sub-channel is assigned according to a service priority class among a plurality of subscriber apparatuses.   The method of claim 1, wherein the digital signals are in different nominal bandwidths. A method of communicating digital data over a wireless physical medium, wherein the digital data packet is at least basic rate interface (BRI) data as received from a terminal device by an integrated services digital network (ISDN) modem. Provided at a transfer rate, the wireless physical medium uses code division multiple access (CDMA) radio frequency channel digital encoding;
a) Specify multiple orthogonal codes for each CDMA channel, thereby providing multiple subchannels that support only data rates slower than the BRI data rates supported by ISDN modems;
b) buffering the data received from the ISDN modem until the minimum number of data elements that need to be transmitted is reached;
c) requesting at least one subchannel assignment to the ISDN modem over the wireless physical medium;
d) transmit data using the assigned subchannel;
e) requesting an additional subchannel allocated to communicate from the ISDN modem when a number of buffered data elements exceed a predetermined maximum amount;
f) A digital data communication method for releasing subchannels from allocation to the ISDN modem when a number of buffered data elements do not reach a predetermined minimum limit. A method of allocating bandwidth for the digital signal transmission channel to a subscriber unit for use with a cellular digital communication network having a base station and a plurality of subscriber units to be serviced, the cellular method The digital communication network has a control channel by which a digital signal transmission channel is designated for the communication session for the subscriber unit,
a) allocating a portion of the available bandwidth to the digital signal transmission channel for use by the subscriber device during a communication session in response to a subscriber device request for the digital signal transmission channel; ,
b) Bandwidth allocation for deallocating the portion of the available bandwidth from use by the subscriber unit if no digital communication signal is generated from the subscriber unit for a predetermined amount of time during the communication session. Method. A method of allocating bandwidth for the digital signal transmission channel to a subscriber unit for use with a cellular digital communication network having a base station and a plurality of subscriber units to be serviced, the cellular method The digital communication network has a control channel by which a digital signal transmission channel is designated for the communication session for the subscriber unit,
a) in response to a request of a subscriber device for digital communication signal transmission, the available selected for use by the subscriber device during a communication session, to the extent that can meet the needs of the subscriber device Allocate a portion of the bandwidth,
b) deallocating a predetermined portion of the selected portion of the available bandwidth from the subscriber device if no digital communication signal is generated from the subscriber device for a predetermined amount of time during the communication session; Instead, a bandwidth allocation method that allows the predetermined portion of the selected portion of the available bandwidth to be used by another subscriber unit.

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