CN1905386B - The code division multiple address communication system of bandwidth is distributed according to request selecting - Google Patents

Abstract

A kind of cdma wireless digital communication system, uses minimum bandwidth to provide all types of speeches and data communication for application-specific.This system is according to user's request distribution ISDN bandwidth effectively.Initializing according to user, system is set up channel and generates required extended code to support the peak capacity channel needed for subscriber unit.Reserved part communication spectrum bandwidth is not until subscriber unit actual request.Because perform call setup from the calling of subscriber unit when starting, including the distribution of extended code, subscriber unit can obtain the partial frequency spectrum supported needed for application-specific rapidly.

Description

The code division multiple address communication system of bandwidth is distributed according to request selecting

The application is filing date on May 26th, 1998, Application No. 200510126716.7, invention entitled " according to The code division multiple address communication system of request selecting ground distribution bandwidth " the divisional application of Chinese patent application.

Cross-Reference to Related Applications

The application is the part subsequent application of provisional application No.60/049,637 that on June 16th, 1997 submits to.

Technical field

Present application relates generally to wireless communication system.More specifically, the application relates to wireless digital CDMA (CDMA) Communication system, this system includes base station and multiple users and communicates with subscriber unit foundation according to subscriber unit request or wish The request selecting ground distribution bandwidth of entity.

Background technology

With capability of wireless communication system and the raising of reliability, the application of radiotechnics is increased by telecommunications industry the most significantly Long.Once it only is considered as a kind of digit wireless communication system facilitating method sending Speech Communication and is to provide now form of ownership Communications necessary to, described communication include plain old telephone service (POTS), ISDN (ISDN), can Variable bit rate (VBR) data service, broadband services, private line service and Packet data service.Although transmitting above-mentioned all types of Business is feasible technically, but the massive band width needed for high data rate communication has made the multiple business in these business Become uneconomical.Requirement that the number of users accessing radio digital communication system has increased, width is relied on for every kind of communication Bandwidth is the most unrealistic.

Distribute to wireless communication system the most gradually appreciate for public finite bandwidth.Because can not divide for existing application Joining the extra bandwidth supporting that user increases, the many new developments in telecommunications software and hardware and software have been working on using narrower bandwidth And increase message transmission rate.

More efficiently use distributed bandwidth accordingly, it would be desirable to a kind of and support the high data identical with conventional wired networks The radio digital communication system of rate business.

Summary of the invention

The present invention is a kind of cdma wireless digital communication system, and this system uses a width of application-specific in arrowband to provide all The speech of type communicates with data.This system is according to user's request distribution ISDN bandwidth effectively.Initialize according to user, system Set up channel and generate required extended code to support the peak capacity channel needed for subscriber unit.But, real at subscriber unit Before the request of border, system is not left unused section communication bandwidth.Because holding when starting from arbitrary calling of this particular subscriber unit Row call setup, including the distribution of extended code, subscriber unit can obtain the partial frequency spectrum supported needed for application-specific rapidly.

Therefore, it is an object of the invention to provide a kind of band-spread wireless digital communication system, this system is efficiently used spread spectrum Bandwidth, supports to include the multiple telephone service of POTS and ISDN.

After the explanation understanding embodiments discussed below, other objects and advantages of the present invention will become apparent from.

Accompanying drawing explanation

Fig. 1 is the block diagram of the CDMA bandspread communication system according to the present invention；

Fig. 2 A is the block diagram of subscriber unit of the present invention and the interface of ISDN terminal；

Fig. 2 B is the block diagram of subscriber unit of the present invention and the interface of POTS terminal；

Fig. 2 C is the block diagram of subscriber unit of the present invention and the interface of block terminal；

Fig. 2 D is the block diagram of subscriber unit of the present invention and the interface of broadband connection；

Fig. 2 E is the block diagram of subscriber unit of the present invention and the interface of special line terminal；

Fig. 2 F is the block diagram of subscriber unit of the present invention and the interface of ISDN and POTS network；

Fig. 2 G is subscriber unit of the present invention and broadband and the block diagram of the interface of packet network；

Fig. 2 H is the block diagram of subscriber unit of the present invention and the interface of private line network；

Fig. 3 is the block diagram according to subscriber unit of the present invention；

Fig. 4 is the block diagram according to RCS of the present invention；

Fig. 5 is the program flow diagram for ISDN service dynamic distribution bandwidth；

Fig. 6 A and 6B is the flow chart setting up Bearer Channel for POTS business between subscriber unit and RCS；

Fig. 7 represents the layered protocol of communication between subscriber unit and RCS；

Fig. 8 A illustrates the simplification carrier conversion method originated by subscriber unit；

Fig. 8 B illustrates the simplification carrier conversion method originated by RCS；With

Fig. 9 A and Fig. 9 B is the flow chart setting up Bearer Channel for ISDN business between subscriber unit and RCS.

Detailed description of the invention

Will refer to accompanying drawing explanation preferred embodiment, in whole accompanying drawings, same label represents same parts.

The system of the present invention uses the radio link between one or more base stations and at least one remote subscriber units Local loop telephone business is provided.In the exemplary embodiments, this radio link is described as a fixed subscriber unit (FSU) communication and between a base station, but this system be equally applicable to include the system of multiple base station, described base station have to Fixed subscriber unit and the radio link of moving user unit (MSUs).Therefore, fixing and moving user unit will claim at this Make subscriber unit.

Seeing Fig. 1, base station 101 is to local switch 103 or other telephone network Fabric Interface such as subscriber exchange any (PBX) provide calling connect, and include at least one radio carrier station (RCS) 104,105 ..., 110.One or more RCS 104,105,110 being connected to radio allocation unit (RDU) 102 by link 131,132,137,138,139, RDU 102 leads to Transmission from one meridian to another telephone operator link 141,142,150 sends and reception call setup, control and information signal are right with local switch 103 Connect.Subscriber unit 116,119 is communicated with RCS 104 by radio link 161,162,163,164,165.Alternatively, this Another bright embodiment includes some subscriber units and is functionally similar to " primary user's unit " of RCS 104.Such a is implemented Example can have the connection that can also not arrive local telephone network.

Radio link 161 to 165 is at CDS1800 standard (1.71-1.785GHz and 1.805-1.880GHz), US-PCS Work in the frequency band of standard (1.85-1.99GHz) and CEPT standard (2.0-2.7GHz).Although using this in the described embodiment A little frequency bands, but present invention are equally applicable to include whole UHF and SHF frequency band and all radio frequencies from 2.7GHz to 5GHz frequency band Frequency band.Transmitting and reception bandwidth are to start with the multiple of the 3.5MHz of 7GHz and the multiple of the 5MHz starting from 10MHz respectively.Institute The system of stating includes the bandwidth of 7,10,10.5,14 and 15MHz.In the example embodiment of the present invention, up-link and downlink Between minimum guard band be 20MHz, and wish three times of at least signal bandwidth.Duplex Spacing 50 to 175MHz it Between, described invention use 50,75,80,95 and 175MHz.Other frequency can also be used.

Although this system can use the different apread spectrum bandwidths centered by a carrier wave for launching and receiving spreading channel, But the present invention is easy to expand to use multiple apread spectrum bandwidth for launching channel and multiple apread spectrum bandwidth for receiving channel System.It is alternatively possible to use same apread spectrum bandwidth for launching and receiving channel, wherein up-link and downlink will account for Use identical frequency band.The present invention is also easy to expand to multiple CDMA frequency band, each frequency band transmit different one group of message, Up-link, downlink or uplink and downlink link.

Use QPSK (QPSK) modulation and Nyquist (Nyquist) shaping pulse at radio link 161 Fat binary code element information is transmitted on 165.It is also possible, however, to use other modulation technique, including but not limited to partially Put QPSK minimum shift keying (MSK), Gauss phase-shift keying (PSK) (GPSK) and M system phase shift keying (MPSK).

Radio link 161 to 165 combines WCDMA (B-CDMA^TM) technology is as up-link and downlink Transmission mode on direction.CDMA (also referred to as spread spectrum) communication technology used in multi-address system is known, and by Donald Schilling is described in United States Patent (USP) US 5,228,056 of entitled synchronization spread spectrum communication system and method.Institute System of stating uses direct sequence spreading technology.The generation of CDMA manipulator can be the spread spectrum spreading code sequence of pseudo noise sequence, and Using extended code sequence is the plural direct sequence modulation that homophase (I) and orthogonal (Q) channel perform QPSK signal.Generation pilot tone is believed Number, the extended code of the most unused data modulation, and send together with modulated signal.Pilot signal is used for synchronizing, carrier phase recovery And for estimating the impulse response of radio channel.Each subscriber unit 111-118 include code generator and at least one CDMA modulator and demodulator, both collectively constitute cdma modem.Each RCS 104,105,110 has at least one Code generator adds enough CDMA modulator and demodulators all logic channels in subscriber unit uses.

CDMA demodulator uses and rationally processes despread signal to reduce or to eliminate multipath transmisstion effect.Radio link props up Holding data rate is 8,16,32,64,128 and a plurality of Traffic Channel of 144kb/s.The physical channel being connected with Traffic Channel with The speed work of 64k code element/second.Other data rate can be supported and Forward Error Correction (FEC) can be used to encode.For Described embodiment, uses 1/2 code rate and the FEC of constraint a length of 7.Can be used it according to coding generation technique used Its speed and constraint length.

Refer again to Fig. 1, RCS 104 by a plurality of RF link or the ground of such as 1.533Mb/s DS1,2.048Mb/s E1 Face link 131,132,137 or HDSL form dock with RDU 102 to receive and send digital data signal.Although these are Typical telephone operator standard interface, but the present invention is not limited in these digital data formats.The RCS line interface of demonstration Line coding (such as HDB3, B8ZS, AMI) is decoded and extracts or delta frame information by (not showing in Fig. 1), performs to report to the police and business Signaling capability and the special loopback of channel and parity checking function.This provides the 64kb/ for processing for RCS 104,105,110 S pcm encoder or 32kb/s ADPCM corded telephone Traffic Channel or ISDN channel, hereafter will be described in more detail.According to sequence Column-generation technology can use other voice compression technology.

The system of the present invention is also the carrier between POTS business and ISDN business support RCS 104 and subscriber unit 111 Modifying rates.Subscriber unit 111-118 can with the telephone unit 170 shown in Fig. 2 A-2E, local switch (PBX) 171, Data terminal 172, isdn interface 173 or other type of equipment interconnection.Input from telephone unit 170 can include speech, Voiceband data and signaling.Although present invention can be suitably applied between multiple subscriber unit 111-118 and multiple RCS 104-110 Communication, for simplicity hereinafter with reference to a particular subscriber unit and RCS.If the signal of input subscriber unit is not several Word, subscriber unit 111 converts analog signals into Serial No. to be transferred to RCS 104.Subscriber unit uses such as ADPCM Voice data is encoded by technology with the speed of 32kb/s or lower.RCS 104 detection rates voice band number higher than 4.8kb/s According to or facsimile data with amendment Traffic Channel bearer rate for uncoded transmission.The A rule of signal, u can be performed before being transmitted Restrain companding or do not perform.As is well understood in the art, the data compression technique for numerical data is the most empty The deletion of not busy mark can be used for saving capacity and minimizing interference.

Different close-loop power controlling methods is used to control RCS 104 and user's list for downlink with uplink direction The transmitted power level of radio interface between unit 111.Automatically forward power control (AFPC) method determines downlink transmission Power level and automatic reverse power control (ARPC) method and determine up-link transmission power level.Subscriber unit 111 and RCS 104 logical control channels being used for transmission power control information work with the renewal rate of at least 16kHz.Other embodiments can make With faster or slower renewal rate, such as 64kHz.These algorithms guarantee that user emission power is maintained at the receivable bit error rate (BER), maintain minimum system power to save power and to make the power level of subscriber unit 111 be maintained to be connect with RCS 104 On the approximately equalised level received.

In the ready mode of subscriber unit 111, native system also uses and optionally safeguards Poewr control method.When user is single When unit 111 is stand-by or shuts down to save power, sometimes responds the maintenance power control signal subscriber unit 111 from RCS104 and open Dynamic to adjust the setting of its Initial Trans level.By RCS 104 by measuring received power level and the basis of subscriber unit 111 The power level of system also calculates required Initial Trans and determines and safeguard power control signal.The method shortens user Unit 111 obtains channel to start the time of communication, and reduces the initial transmission mistake launched before power at close-loop power control The transmitted power level preventing subscriber unit 111 in journey becomes Tai Gao and disturbs other channel.

RCS 104 is from such as it is not limited to the interface circuit of E1, T1 or HDSL interface obtains clock synchronization.RCS 104 it be also possible to use agitator generates the internal clock signal of oneself, and this agitator can be by global positioning system (GPS) receiver Adjust.RCS 104 generates the overall pilot codes that can be obtained by remote subscriber units 111.All transmission channels of RCS 104 with Overall situation pilot channel synchronization.The extension code-phase of the code generator (not showing in Fig. 1) of logical channel it is used in RCS 104 Position also with the overall situation pilot channel extended code Phase synchronization.Similarly, all users receiving RCS104 overall situation pilot codes are single It is Tong Bu with overall situation pilot codes that unit 111-118 makes the extension of their code generator conciliate augmentation code phase.

Typically, the channel of prior art is counted as communication path, this communication path be interface a part and can with connect Other path of mouth distinguishes, and does not consider its content.But, for cdma communication, each communication path is come by their content Difference.All logic channels of the present invention and subchannel are mapped to the QPSK data of 64,000 public code elements (ksym/s) per second Stream.Making some channels Tong Bu with associated pilot code, this pilot code is generated and performs similar function by overall situation pilot code.System System pilot signal is not counted as logic channel.

Some logical channel are used on RF communication link between RCS 104 and subscriber unit 111.Every logic Communication channel or there is a fixing predetermined extended code or there is the extended code of a dynamic distribution.For making a reservation for and dividing The extended code joined, encoding phase is all Tong Bu with overall situation pilot codes.

Extended code is by seed (seed) appointment for generating coding.Many " main seed ", part composition is had in RDU The main seed of the overall situation, remaining composition distributes main seed.These main seeds are distributed to RCS 104 by RDU 102 as required.The overall situation Main seed generates all global channel used in a community by RCS104 codings.And distribute main seed for generating two grades Distribution seed.One main distribution seed generates 57 (57) individual secondary distribution seeds.Each secondary distribution seed is transfused to RCS 104 and subscriber unit 111 in code generator with generate one component allocating channel coding thus support every communication link.Excellent Select in embodiment, distribute each RCS104 mono-the main distribution kind of the main seed of the overall situation and two for generating global channel coding Son.Therefore, RCS 104 and its relative users unit 111-118 can at most generate 114 secondary distribution seeds.By RCS 104 Distribute each secondary distribution seed to generate for the coding of active link, thus allow enough codings for up to 114 Communication link simultaneously.

Logical channel is divided into two groups: 1) global channel；With 2) distribution channel.Global channel group include or from RCS 104 transmits to all subscriber unit 111-118 or transmits to RCS 104 from any user unit 111-118 and do not examine Consider the channel of subscriber unit 111-118 mark.Channel in distribution channel group is to be exclusively used in RCS 104 and particular subscriber unit The channel of communication between 111.

For global channel group, global channel group provides: 1) broadcast control logical channel, it is provided that point to multi--point business For to all subscriber unit 111-118 broadcasts with to subscriber unit 111-118 beep-page message；With 2) Access Control logic Channel, provides point-to-point service for subscriber unit 111-118 access system and to obtain distribution channel on global channel.This Bright RCS104 has a broadcast control logical channel and a plurality of Access Control logic channel.The subscriber unit 111-of the present invention 118 have at least one broadcast control logical channel and at least one Access Control logic channel.

The global logic channel controlled by RCS 104 is that broadcast can about which bar Traffic Channel current and which bar access channel The quick broadcast channel (FBCCH) of the information that quickly changes, and broadcast changes at a slow speed system information and beep-page message at a slow speed Broadcast channel (SBCCH).

Subscriber unit 111 uses access channel (AXCH) to start with RCS 104 and communicates and access distribution channel.Every AXCH It is furnished with the control channel (CTCH) from RCS 104 to subscriber unit 111.RCS 104 uses CTCH to confirm and response subscriber unit The access request of 111.Synchronous transfer short circuit enters pilot tone (SAXPT) and the long pilot tone (LAXPT) that accesses to initialize together with AXCH Access and provide time and phase reference to RCS 104.Power is launched to initialize access RCS when subscriber unit 111 improves SAXPT it is transmitted from when 104.Because SAXPT is relatively short coding, it allows RCS 104 quickly to detect subscriber unit 111 And avoid the power of subscriber unit 111 too high." short code is used in a cdma system entitled disclosed in December in 1998 25 days Control initialization power raise method " United States Patent (USP) US 5,841,768 in described in more detail about use SAXPT rises the more details of high emission power.Before RCS 104 detects SAXPT, subscriber unit 111 is not launched any Other signal.Once detecting SAXPT, subscriber unit 111 to start to launch to RCS 104 provides time and phase reference and allows RCS 104 determines the LAXPT of channel impulse response.

For distribution channel group, this group includes controlling patrolling of individual communications links between RCS 104 and subscriber unit 111 Collect channel.When forming distribution channel group, set up the power control logic message connected for every uplink and downlink a pair and believe One or more pairs of Traffic Channel is also set up according to connection type in road.Carrier controls the forward error needed for function executing and controls, carries Body modifying rates and encryption function.

The most each subscriber unit 111-118 has at least one distribution channel group, and each RCS 104-110 has multiple distribution channel group, and often group is gradually available for every communication link.Once it is successfully established communication link and is this Communication link sets up the distribution channel group of logic channel.This distribution channel group includes that the encryption in sending, FEC coding and multichannel are multiple With with receive in deciphering, fec decoder and DeMux.

Each distribution channel group provides one group towards the communication link of point-to-point service and specifying RCS 104 and specifying use Two-way operation between family unit 111.The distribution channel group formed for communication link can control the RF relevant to individual communications links Multiple carriers in communication channel.Multiple carriers are used for transmitting distributed data and such as but are not limited to ISDN.Distribution channel group Can be that bearer rate amendment function provides dual service channel to accelerate to be transformed into for high-speed facsimile and modem traffic 64kb/s PCM.

It is Dedicated Signaling Channel according to the distribution logic channel that success communication link is formed and is included in distribution channel group Call wire (OW), APC channel and one or more Traffic Channel (TRCH), this Traffic Channel be 8 according to supported business, 16, the carrier of 32 or 64kb/s.For voice service, can support on a traffic channel moderate rate encoded voice ADPCM and PCM.For ISDN type business, two 64kb/sTRCH form B channel and a 16kb/sTRCH formation D channel.Alternatively, APC subchannel can independently on the CDMA Channel of oneself modulate, or with Traffic Channel or OW channel time division multiplex.

Each subscriber unit 111-118 of the present invention at most can support three Traffic Channels simultaneously.Subscriber unit is the most handy Make POTS subscriber unit 112 or isdn user's unit 115.Although not supporting ISDN according to POTS subscriber unit 112 of the present invention Business, but can be any one type of service dynamic bandwidth allocation resource.Such as, POTS subscriber unit 112 can set up one add POTS circuit is also removed, or isdn user's unit 115 can dynamically increase B channel and transmits carrier or they removed.Right In the Dynamic Bandwidth Allocation of POTS business, bearer type is modified as 64kb/s not from 32kb/s by current 32kb/sADPCM business Coded data is to support facsimile transmission.Determined the appearance of facsimile call by the appearance of monitoring 2100Hz answering tone by RCS 104.

For the Dynamic Bandwidth Allocation of ISDN business, RCS 104 monitors ISDN D channel massage to determine when to ask B letter Road and when being removed.Once RCS 104 determines needs to change Bearer Channel distribution, and RCS 104 initializes dynamic carrier and divides Join process, this process is described more fully below.Three kinds of logic channels of TRCH to user data mapping as shown in Table 1:

Business	TRCH(0)	TRCH(1)	TRCH(2)
				16kb/s POTS	TRCH/16	Unused	Unused

32+64kb/s POTS (during BCM)	TRCH/32	TRCH/64	Unused
				32kb/s POTS	TRCH/32	Unused	Unused
64kb/s POTS	Unused	TRCH/64	Unused
				ISDN D	Unused	Unused	TRCH/16
Numeral LL@64kb/s	TRCH/64	Unused	Unused
				Numeral LL@2 × 64kb/s	TRCH/64	TRCH/64	Unused
Simulation LL@64kb/s	TRCH/64	Unused	Unused

Table one: the mapping of type of service to three kind available TRCH channel

Subscriber unit 200 constructed in accordance is general as shown in Figure 3.Subscriber unit 200 includes receiver section 202 With transmitter section 204.Antenna 206 receives signal from RCS 104, and this signal is filtered by band filter 208, band filter 208 have the bandwidth doubling spreading rate and the mid frequency being equal to spread spectrum system bandwidth center frequency.Made by frequency mixer 210 With constant frequency (Fc) local oscillator, the output of wave filter 208 is downconverted into baseband signal.Then by PN receiver To the output that frequency mixer 212 is one PN sequence spread spectrum decoding frequency mixer 210 of every logic channel applying in maker 214.Mixed Frequently the output of device 212 is transfused to coder 218, and this coder 218 docks with communication entity 220.

Baseband signal from communication entity 220 such as Fig. 2 A-2E shown device is adjusted by coder 218 pulse code System.32kb/s adaptive pulse code modulation (ADPCM) is preferably used.PCM signal is applied in PN transmitter maker 224 Frequency mixer 222.Frequency mixer 222 makes PCM data signal be multiplied with PN sequence for every logic channel.The output of frequency mixer 222 Being applied to low pass filter 226, its cut-off frequency is equal to system chip rate.Then the output of wave filter 226 is applied to mixing Device 228 by up-conversion suitably, determines as being applied to the carrier frequency Fc of other terminal.Then the signal after up-conversion is by band Bandpass filter 230 is to the wideband RF amplifier 232 driving antenna 234.Although illustrating two antennas 206,234, preferred embodiment Including the duplexer for launching and receive and individual antenna.Digital signal processor (DSP) 236 controls acquisition process and connects Receipts machine and transmitter PN maker 214,224.

The constructed in accordance base station 101 including multiple RCS 104,105,110 is as shown in Figure 4.For the sake of simplicity, Only one RCS 104 of diagram.Base station 101 includes receiver section 302 and transmitter section 304.Antenna 306 connects from subscriber unit Collecting mail number, this signal is filtered by band filter 308, and band filter 308 has and doubles the bandwidth of spreading rate and be equal to The mid frequency of spread spectrum system bandwidth center frequency.Frequency mixer 310 uses constant frequency (Fc) local oscillator by wave filter 308 Output be downconverted into baseband signal.Then by applying a PN sequence to frequency mixer 312 in PN receiver maker 314 Output at each modem spreading spectrum and decoding frequency mixer 310.Then the output of frequency mixer 316 is sent to RDU 318.

Baseband signal is received from RDU 318.32kb/s ADPCM signal is preferably used.ADPCM or PCM signal are launched at PN Machine maker 324 is applied to frequency mixer 322.Frequency mixer 322 makes ADPCM or PCM data signal be multiplied with PN sequence.Frequency mixer The output of 322 is applied to low pass filter 326, and its cut-off frequency is equal to system chip rate.Then the output of wave filter 326 is executed Add to frequency mixer 328 and by up-conversion suitably, as determined by the carrier frequency Fc being applied to other terminal.Then after up-conversion Signal is by the wideband RF amplifier 332 of band filter 330 to driving antenna 334.Although illustrating two antennas 306,334, Preferred embodiment includes the duplexer for launching and receive and an antenna.Digital signal processor (DSP) 336 controls to gather Process and Receiver And Transmitter maker 314,324.

This system provides wireless link between RCS 104 and multiple subscriber unit 111-118.In order to save as much as possible Bandwidth, the bandwidth needed for specific communications required for transfer rate is supported in the distribution of this Systematic selection ground.So, system guarantees effectively Ground uses bandwidth.Such as, referring again to table one, can be effective by adaptive pulse code modulation (ADPCM) channel of 32kb/s Ground transmits Speech Communication.But, high-speed facsimile or data modem unit signal demand at least 64k/bsPCM signal are with reliably Transmission communication.It addition, although subscriber unit is paid for ISDN business, this business includes the B channel and of two 64kb/s The channel of bar 16kb/s, but seldom use whole ISDN capacity always.Multiple different message transmission rate also can by originating and End-node uses.

This originate with end-node can include computer, facsimile machine, ACAU automatic calling and answering unit, data network or this Any combination of a little equipment.For the strong communication of data, before any data are transmitted, must assure that communication system is transformed into Message transmission rate needed for communication node.This system allows for effectively distributing bandwidth and according to user's request at these numbers Dynamically change according between traffic rate.Transmit from low rate (support Speech Communication) to two-forty (support encoding data communication) The amendment of speed guarantees reliably to transmit data rapidly over the communication channels.If it addition, will distribute ISDN D channel and Needing one or two B channel, this system must assure that startup code generator is to support this communication.

For POTS, there are two kinds or revise Bearer Channel (TRCH channel) or increase or remove a new bearer letter The basic condition in road.First, Bearer Channel is revised as 64kb/s noncoding PCM business from the coding ADPCM type of 32kb/s To support facsimile transmission.Second, when when carrying out OA&M calling (internal affairs, manage and safeguard) user's off-hook, or when carry out When pots call starts OA&M calling, increase or remove a new bearer channel.When carrying out OA&M silent call, Yong Hudan Unit 112 can be by the change on A/B interface between monitoring subscriber unit 112 and communicator 170 (on-hook/off-hook sensor) Determine that user is starting a new pots call.In August, 1998 is may be in about the more details for POTS dynamic bandwidth allocation United States Patent (USP) US5,799,010 entitled " CDMA (CDMA) communication system " disclosed in 25 days finds.

For ISDN business, Dynamic Bandwidth Allocation refers to select in D, D and B or D and 2B Bearer Channel configure as required Distribute to selecting property D and B channel and removed when they are idle.ISDN D channel transmits and controls message and work as isdn call Also can not be removed when carrying out.Therefore, the Dynamic Bandwidth Allocation for ISDN business only relates to increase and the dismounting of B channel.

See Fig. 5 to will be clarified in more detail according to the present invention for the process 400 for ISDN service dynamic distribution bandwidth.When When starting an isdn call, initially set up D channel (step 402).By the message on channel D from caller ISDN device to quilt It is the bandwidth (step 404) needed for ISDN device transmission application-specific.These message are passed through with HDLC form and RCS 104 These message (step 406) of HDSL interface monitor.Once RCS 104 determines how many B channel (step 408) of needs, and it starts Aloft set up these Bearer Channels (step 410) on interface.During isdn call, RCS continues to monitor on D channel HDLC message also determines whether to be switched in or out additional B channel.If additional B channel should be access in or disconnect, RCS 104 Start aloft to set up or remove Bearer Channel (step 414) on interface.

Will refer to Fig. 6 A and 6B and describe the flow chart representing that Bearer Channel sets up simplification process 600.Sending SAXPT (step Rapid 604) time, subscriber unit 111 quickly improves its transmitting power (step 602).When RCS 104 detects SAXPT (step 606) Time, business indication bit is set to " red " (step 608) on FBCCH by it, and to notify subscriber unit 111, it has been detected. RCS

104 send FBCCH (step 610).Subscriber unit 111 monitors FBCCH (step 612) and when it finds FBCCH On " business instruction " stop when reddening quickly raising (step 614).Then (step 618) subscriber unit when sending LAXPT 111 start to improve at a slow speed it launches power (step 616).When RCS obtains LAXPT (step 620), it passes through on CTCH SYNC-OK message informing subscriber unit 111 (step 622).This accomplishes the transmitting power raising part of access procedure.

After subscriber unit 111 receives SYNC-OK message on CTCH (step 624), it sends access on AXCH Request message (step 626).Upon receipt of this request (step 628), RCS 104 is with including allocated code seed on CTCH The reception (step 630) of message authentication AXCH message.Subscriber unit 111 detects on AXCH and confirms to transmit allocated code seed Carrier confirm message (step 632 and 634), RCS 104 detects this confirmation (step 636).Consult code conversion now, used Family unit 111 and RCS 104 is changed to use this allocated code (step 638 and 640) simultaneously.Now establishes Bearer Channel.

Fig. 7 represents the layered protocol of communication between subscriber unit 111 and RCS 104 and joins with open system interconnection (OSI) Examine model corresponding.Physics (PHL) layer execution following function: 1) generate CDMA coding；2) transmitter and receiver is made to synchronize；3) Carrier is provided for media interviews control (MAC) layer；4) power level specified on the CDMA coding specified by MAC and with MAC Extension and transmitted bit；5) received signal strength is measured to allow automated power to control；With 6) generate and transmit pilot signal. MAC layer execution following function: 1) it is that forward error correction (FEC) encodes and decodes；2) distribution CDMA coding；3) encrypt and decipher；4) There is provided by suitable encryption and the carrier of error correction；5) framing, error detection and difference MAC peer message and data；6) link controls (DLC) Frame；With 7) process automated power control information.Data link control layer (DLC) provides zero defect between the high level of protocol stack Link.

As shown in Figure 8 A, the signaling between subscriber unit 111 and RCS 104 relates to MAC and the DLC layer of this agreement.Once Set up Bearer Channel for POTS business as mentioned above, this business can with and keep constant until it is removed or until at the same time Facsimile transmission or the second calling it is modified to support in the case of carrying out OA&M calling or pots call.One is carried out when OA&M calling and subscriber unit 111 start a POTS service call, enter the process shown in Fig. 8 A.The figure shows by user The simplification carrier conversion method that unit 111 is initiated.Message is in the data link control layer (DLC) of subscriber unit 111, media interviews Transmit between equivalent layer in key-course (MAC) and RCS 104.First, the DLC layer of subscriber unit 111 is to subscriber unit 111 MAC layer sends a convert requests, and this convert requests is submitted to the MAC layer of RCS 104 by this MAC layer.RCS 104 is in MAC layer On to subscriber unit 111 send one confirm and to RCS 104 DLC layer send one conversion instruction.At subscriber unit 111 In, the conversion sent from RCS104 on the mac layer confirms to be sent to the DLC layer of subscriber unit 111.

Send an OA&M to same subscriber unit 111 exhale when carrying out a POTS service call and RCS 104 When crying, enter the process shown in Fig. 8 B.The figure shows the simplification carrier conversion method initiated by RCS 104.RCS 104 is at MAC A conversion instruction message is originated to subscriber unit 111 on Ceng.Then subscriber unit 111 relays this message by DLC layer.

Will refer to Fig. 9 A and 9B explanation and set up Bearer Channel for ISDN.Step 902-940 step corresponding to Fig. 6 A and 6B Rapid 602-640 is identical.But, need after subscriber unit 111 and RCS104 is all transformed into allocated code (step 938 and 940) Want some additional steps.Once subscriber unit 111 and RCS 104 is transformed into allocated code (step 938 and 940) ISDN D channel It is made available by.Here the S/T interface between subscriber unit 111 and ISDN device has been available.RCS 104 starts monitoring D channel massage (step 942) of HDLC form.Once detect that application-specific needs one or more B channel (step 944), RCS 104 starts aloft to set up these Bearer Channels on interface.Then continue with according to the process shown in Fig. 5.For this MAC with the DLC message stream of process is identical with Fig. 8 B.

It is switched in or out the Bearer Channel for POTS and ISDN by identical message stream.By the corresponding word of D channel massage Value instruction Bearer Channel in Duan is to access also to be off.Therefore the flow chart in Fig. 8 B be applied to dynamic access Bearer Channel with And dynamically disconnect Bearer Channel.

Although by describing the present invention referring in detail to some specific embodiment, these details will refer to the property led rather than limit Property processed.It should be apparent to those skilled in the art that without departing from present invention disclosed spirit and scope in instructing at this In the case of, various change can be carried out in mode of operation and structure.

Claims (9)

1., in the method for distributing bandwidth, the method includes:

Set up communication channel with communication unit, wherein transmit by using this communication channel to be transmitted with original data rate；

Monitor described communication channel, and determine that the data rate after adjustment is to transmit described in continued support；And

In response to described monitoring and determine, set up or remove extra communication channel, wherein said additional communication channels by For transmitting described transmission, and described communication channel at least one carry power time-multiplexed with business datum Control information.

Method the most according to claim 1, also includes:

Send and launch power command for the transmitted power level setting described communication channel.

Method the most according to claim 1, wherein said monitoring determines the bandwidth of needs.

Method the most according to claim 1, wherein when described extra communication channel one of them idle time, this is extra Communication channel is removed.

Method the most according to claim 1, wherein said extra communication channel is through distribution, to support from described The described transmission of communication unit.

Method the most according to claim 1, bandwidth the most as required, distribute a bandwidth to described communication unit.

Method the most according to claim 6, wherein said extra communication channel according to the bandwidth distributed by dynamically Ground increases.

Method the most according to claim 1, the extended coding of wherein said transmission and any extra communication channel is Dynamically distribute.

Method the most according to claim 1, the method also includes receiving, from described communication unit, the bandwidth that instruction is wanted Requirement.

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