CN1080979C - Semi-hard handoff in a cellular telecommunications system - Google Patents

Abstract

The present invention relates to a novel CDMA switching mode, particularly to semihard switching which is used in a CDMA honeycomb communication system which comprises a mobile exchanger (MSC), a base station (BS) and a mobile station (MS). The semihard switching generates in a border base station (BS12) which is positioned at the border of two service areas (SA1, SA2), and the two service areas are controlled by two adjacent mobile exchangers (MSC1, MSC2). The border base station is connected with the two mobile exchangers, so both the two mobile exchangers can access the border base station.

Description

Cellular communication system and semihard changing method thereof

The present invention relates to cellular communication system.Particularly a kind of for switching improved novel system between mobile radio station and the base station, these base stations are in the different mobile switching centres that are connected in the cellular communication system.

Code division multiple access (CDMA) modulation system is a kind of in the some kinds of digital communication technologies, and these technology are used for making a plurality of mobile subscribers can use same radio band jointly, and cellular communication system comes to this.The wireless access technology that other people know has time division multiple access (TDMA) and frequency division multiple access (FDMA).Very suitable really with the soft handover notion that the present invention is closely related to above-mentioned three kinds of multiple access techniques, compare with conventional hard handover approach, will increase power system capacity, reduce the calling of leakage.Yet, in CDMA, must use soft handover, because conventional direct-cut operation can cause inferior systematic function.Background of the present invention is that it is applied to a cdma cellular communication system, but should not be understood that the present invention is only limited to CDMA.An application example that CDMA is used for cellular communication system is arranged, in " code division multiple access (CDMA) being applied to the system design of digital cellular and personal communication network " literary composition, this example is had a detailed description, the paper author is Allen Salmasi and Klein S.Gilhousen., be published in the 41st IEEE mobile technology meeting, meeting was held in St. Louis, the Missouri State in 19-22 day in May, 1991.

In above-mentioned paper, a kind of direct sequence CDMA (DS-CDMA) has been described, hereinafter be abbreviated as CDMA technology, utilize some user's mobile radio stations (MS) of this technology and base station (BS, or be called the sub-district node) use the cdma wireless spread-spectrum signal, on up link (from the mobile radio station to the base station) and down link (from the base station to the mobile radio station), communicate.Fig. 1 illustrates the network configuration of a kind of typical C DMA communication system of prior art.Base station BS 10,12,14,16 will from or these cdma wireless conversion of signals of passing to user's mobile radio station 20 become can and ground communication transmission equipments, as widely used pulse code modulation (pcm) circuit arrangement, the signal of the service form that matches.The base station then passes to mobile switching centre 1 or 2 (MSC is called mobile switch or MTSO (MTSO) again) to these subscriber signals on the uplink and downlink link direction, further processes.

Above-mentioned user communications signals comprises digitized voice signal and control information (being also referred to as signaling).MSC carries out multiplexing and conversion operations to above-mentioned branch road, and sends voice signal to another user, for example the user in public switch telephone network (PSTN).MSC also generates signaling information, explains signaling information, and signaling information is reacted, and controls the whole communication links between the user thus.These communication link controlled function comprise the incident that management is relevant with general calling, as call establishment and dismounting, also comprise the incident that management is relevant with the cdma wireless link, as the decline of cdma wireless link quality and the beginning of consequential switching.

If CDMA be applied in the land mobile communication system typical in, during the large-scale sub-district, the propagation average delay time in the multi-path wireless communication environments is usually greater than the chip lengths of DS-CDMA signal.Make CDMA to work under asynchronous mode like this, consequently the orthogonality of spread spectrum multiple access access subscriber signal can't only obtain by orthogonal intersection.Therefore, the interference that the system self of influence communication brings out does not exist only among the signal from different districts, also has quite a few (to be called the interference CDMA sub-district in) within the signal of same sub-district.To such CDMA Cellular System, an important goal in overal system design is exactly the interference that reduces as far as possible the extra CDMA of generation in communication user, and, receive and be used to the energy in desired CDMA subscriber signal as far as possible.The requirement of this system design, although other access mode to cellular communication system also is a general requirement, but to FDMA and tdma system, this requirement is not as so strict to CDMA, because in these two kinds of systems, interference can utilize the intrinsic characteristic of TDMA and FDMA respectively and avoided in the sub-district, and can utilize preplanned honeycomb fashion frequency recycling method to be limited.Therefore, with FDMA, the TDMA difference, CDMA works under the mode of strict limit interferences.

Though soft handover also can increase the power system capacity of TDMA, its effect is that example illustrates the present invention with a cdma cellular telecommunication system not as cdma system below.

The mode that the above-mentioned cdma system design object of several realizations is arranged can be considered to the exemplary embodiment of above-mentioned cdma cellular telecommunication system.For example, so-called MS transmitting power close-loop control mode, its purpose is to make the signal quality of all up links of receiving in the BS to remain unanimity, and this is for the vertiginous radio propagation channel background with rapid fading and slow fading process.For this reason, the base station is measured the Eb/No value that the CDMA up link of each bar MS is come periodically, and this value has shown the quality of signal, sends corresponding power control command to MS by down link then, is used for correspondingly regulating the power of its CDMA reflector.In the ideal case, the CDMA uplink signal of all MS that BS receives has identical quality, according to predetermined quality threshold value, only needs minimum adjusting just can keep communication link.

Another embodiment that realizes the aforementioned system purpose of design is in a cdma communication process of working, the auxiliary moving soft handoff that the binding signal diversity merges, and this and the closely-related method of the present invention will be set forth below.

The auxiliary moving soft handover that the binding signal diversity merges comprises following method: on the uplink and downlink link, via first and second BS, transmit user communications signals on the span line between MS and the MSC simultaneously, carry out the signal diversifying reception to improve the subscriber signal quality at MS and MSC.The overlapping part that enters the first and second BS overlay areas as the MS that communicates by letter at first with a BS, and the 2nd BS MSC when MSC reports the signal of having received sufficient intensity just need use above-mentioned soft handover method.In the soft switching process that the binding signal diversity merges, MS can not interrupt with communicating by letter of MSC.MSC typically adopts the code speech frame selectivity of back detection/decoding, numeral to merge.

In order to realize the satellite report function of MS in the soft handover starting process, all BS will send a down link CDMA reference signal, are called pilot signal.When MS roamed in the coverage of cdma cellular communication system, with when a BS communicates by letter, periodically demodulation was therefrom derived corresponding pilot signal quality indication from the pilot signal of different neighbor bss.Moreover, the pilot signal Eb/N that measures _bBe worth, can be used as the indication of signal strength signal intensity/quality, indicate to determine a station list that can supply soft handover to select, and send to MSC in the mode of signaling information with this.It should be noted that a BS also detects carrying out the CDMA downlink signal quality continuously, and the result of these detections, send to the indication of a soft handover requirement of MSC.

Usually, if MS reports, the pilot signal of a BS not only, and second BS pilot signal quality also satisfies the predetermined thresholding of MS well enough, and MSC and the 2nd BS also can obtain to carry out the required resource of soft handover, so MSC just begins to carry out the soft handover that the binding signal diversity merges.Then, by a BS, under the commander of MSC with signaling method, MS begins soft handover, and the commencing signal diversity merges on down link.

In addition, MSC begins the additional transmission of subscriber signal via the 2nd BS, and the diversity of beginning subscriber signal merges on uplink direction.These two BS that participate in this thing carry out aforesaid close-loop power controlling method automatically.Its CDMS transmitting power of MS is set to the smaller value of two BS power demand levels, with the extra interference that reduces other cdma communication link is produced.

At last, in MS is in the coverage of the 2nd BS definitely, and the pilot signal of coming from a BS that receives has been reduced to the required threshold value of predetermined MS when following, MS gives MSC with this situation report, MSC then determines the diversity of ending soft handover and signal to merge, and only utilizes the 2nd BS to keep cdma communication then.

When MS was mobile in the coverage of cdma cellular communication system, according to the indication of measured cdm signal quality, the soft handover that this binding signal diversity merges will constantly repeatedly carry out.

Some modern TDMA cellular communication systems also utilize the help of MS, measure with corresponding M S downlink signal quality and come requirement once from the switching of a BS to the two BS as index, with aforesaid way a lot of similarities are arranged.Yet these systems usually use a kind of so-called hard handover approach, and MS is according to the instruction of MSC, cut off and the getting in touch an of BS, be tuned to come on the TDMA wireless channel of indicated the 2nd BS, recover communicating by letter of up link and down link then.MS can not communicate by letter with more than one BS simultaneously, like this, the signal diversifying that can not take place to occur in the above-mentioned soft handoff in MS and MSC merges, this conventional method for hard switching also can be applied to CDMA in a similar fashion, but because following cdma system capacity aspect is not done as far as possible like this.

In the notion relevant with soft handover and direct-cut operation, the predetermined threshold value of mentioning in the past also is known as the switching tolerance limit, and it is used for the candidate BS of measurement to determine to switch with downlink signal quality.For avoiding when MS enters the smeared out boundary of two neighbor bss wireless signal overlay areas, cause that frequent switching (be called and switch ping-pong) must use these to switch tolerance limit and time average processing method simultaneously.This frequent switching can cause that MSC handles the overload of capacity.Be the CDMA soft handover that control binding signal diversity merges, the switching tolerance limit can be selected little to about 1-3dBd, compares therewith, is the switching ping-pong of avoiding being harmful to, and conventional direct-cut operation tolerance limit usually needs 6-10dB.

The operation of CDMA of having considered aforesaid interference-limited, choosing little switching tolerance limit is the effectively necessary condition of operation of CDMA.Adopt the necessary bigger direct-cut operation tolerance limit of conventional CDMA direct-cut operation can reduce the cdma system capacity significantly.Have only under special circumstances, the cdma cellular communication system just can adopt direct-cut operation, and can not be with its general modfel as system operation.Semihard of the present invention switches the deficiency that can remedy conventional hard handover approach.

Another kind of problematic switching is the switching between the MSC, just is connected the switching between the BS on the adjacent MSC.The cellular system that prior art is shown with Fig. 1 is an example, and this situation is described.MS20 can carry out soft handover in the soft handover area SA1 of MSC1 control, also can carry out soft handover in the region S A2 of MSC2.But when it enters the intersection in these two zones, just can not carry out soft handover.For example, when MS20 is in the junctional area of BS12 and BS14, just can not carry out soft handover.Suppose that MS20 is connected with BS12, and it moves to BS14, in prior art system,, from BS12 to BS14 and from MSC1 to MSC2, must carry out the CDMA direct-cut operation between the conventional MSC so if MS20 will be switched to another soft handover area SA2 from soft handover area SA1.Because the necessary switching tolerance limit of direct-cut operation, this conventional direct-cut operation is insecure, and the CDMA capacity is had very adverse influence.

The objective of the invention is to avoid the adverse effect (as reducing power system capacity) that direct-cut operation brings between the MSC of conventional CDMA.

A part of the present invention is a cellular communication system, and it comprises:

A plurality of mobile radio stations;

One first mobile switch;

One second mobile switch;

A plurality of base stations, wherein the second group of base station that only be connected with described first mobile switch, first group of base station only is connected with described second mobile switch, in described a plurality of base stations, having a base station at least is a border base station, is connected with second mobile switch with described first mobile switch simultaneously.

Another part of the present invention is a kind of semihard switching mode, is used for communication control function is switched to described second mobile switch from described first mobile switch, and does not influence the radio communication between described mobile radio station and described at least one border base station.

According to the present invention, used a kind of new CDMA hand-off process mode, hereinafter be referred to as semihard and switch.Semihard switches to occur on the above-mentioned same base station and (hereinafter is referred to as border base station), and this base station is positioned at the intersection of the wireless coverage area that two different mobile switches (hereinafter being referred to as adjacent mobile switch) are controlled.This border base station is connected to this two adjacent mobile switches, also can be linked into this border base station from these two adjacent mobile switches.

The semihard invented switches the switching of the communication control function that is a kind of based on network, from first to second adjacent mobile switch, and does not interrupt ongoing cdma wireless communication between border base station and the mobile radio station.The semihard switching requires that conversion facility is arranged on the base station, is used for the user radio signal of communication is coupled on any adjacent mobile switch that is attached thereto, and this needs in implementing the semihard switching.

By means of the multichannel connection of adjacent mobile switch and the conversion equipment on the border base station, an overlapping soft handover service area is provided between adjacent mobile switch, this does not have in the cellular communication system of prior art.Semihard switches to occur in the overlapping soft handover service area and (is caused by border base station), has avoided the direct-cut operation of disadvantageous conventional COMA inter-exchange like this.

From the detailed description of doing below in conjunction with accompanying drawing, the features and advantages of the present invention can be more obvious.

Fig. 1 illustrates the sketch of the cdma cellular communication system of prior art;

Fig. 2 illustrates the sketch according to a cdma cellular communication system example of the present invention;

Fig. 3 is the block diagram of preferred embodiment that is used for the mobile switching centre of cdma cellular communication system;

Fig. 4 is the block diagram of preferred embodiment that is used for the base station of COMA cellular communication system.

Fig. 2 illustrates the example of a cdma cellular communication system that relates to of the present invention.The system of describing among the figure has improved the CDMA soft handover and the macrodiversity signal folding of prior art, and this has detailed description in " code division multiple access (CDMA) being applied to the system design of digital cellular and personal communication network " literary composition.The paper author is Allen Salmasi and Kleins Gilhousen, is published in the 41st IEEE mobile technology meeting, and meeting was held in St. Louis, the Missouri State in 19-22 day in May, 1991.

BS12 is a boundary B S, is connected to adjacent MSC1 and MSC2 by link 32,34, BS12 while and MSC1, and the connection of MSC2 has enlarged MSC1 effectively, MSC2 soft handover area SA1 and SA2 separately, thus produced an overlapping soft handover area OA.Other is not in the BS10 that covers junctional area, and 14, only need to be connected with single MSC (MSC1 or MSC2).The semihard switching occurs in the overlapping coverage area OA.

The use of the soft handover of semihard switching and prior art is described below.Suppose that MS20 moves to SA2 from soft handover area SA1, pass BS10 successively, 12,14 radio coverage area.

Suppose that MS20 is connected with BS10 at first, and be connected with user's (supposition is the user among the PSTN) of other system, when MS20 continues to move the radio coverage area that enters boundary B S12 by MSC1.Because BS12 is connected on the MSC1 by link 32, begin to carry out according to the soft handover of prior art.MSC1 merges point as signal diversifying, and continues controlling this connection.

When MS20 away from BS10 and near BS12, be terminated MS20 only communicate by letter (via MSC1) with BS12 according to the soft handover of prior art.

MS20 measures constantly from BS10,12,14 pilot signal strength, and return to MSC1 with the form of neighboring cell measurement reporting, interior also the continuation moved to the BS14 direction from BS10 if the intensity of these pilot signals demonstration MS20 is in the area of coverage of BS12 definitely, semihard of the present invention switches and will be started by MSC1, and its process is as follows:

-from the pilot signal quality measurement report that MS20 did, MSC1 recognizes that MS20 is in the overlay area of BS12 really, and continue away from BS10 convergence BS14.In addition, from the cellular network device configuration data, MSC1 recognizes that BS12 also can be inserted (by link 34) by MSC2.Therefore, according to predetermined threshold parameter, can determine MSC1 to switch by MSC1 to the semihard of MSC2.For this purpose, will on digital link 40, keep a circuit that leads to MSC2.MSC1 has also set up one in the down link direction and has connected along separate routes, and new line on the link 40 and branch road 42 from PSTN are coupled together.

-MSC1 sends appropriate signaling information to MSC2, and the semihard that requires to carry out to MSC2 switches, and indicates newly assigned circuit on the transmission link 40 simultaneously.MSC2 then distributes, starts to handling and controlling ongoing resource requirement of communicating by letter.These resources comprise (but being not limited to): carry out the facility that uplink users information frame (being used for the soft handover in the in the future possible SA2) diversity merges; The code conversion equipment that is used for voice communication; Mobile radio station and base station signaling link terminal and suitable control and treatment part.

-MSC2 distributes a circuit on the digital link 32 that is connected with BS12, and sends appropriate signaling information to BS12, and the semihard that requires to carry out among the BS12 switches, and indicates newly assigned circuit on the transmission link 34 simultaneously.

-BS12 utilizes its interchanger 250 (see figure 4)s, and the wireless communication signals that is transmitting between it and the MS20 is transformed in the link 34 on the newly assigned circuit.BS12 will beam back proper signal and give MSC2 then, announce this conversion and complete successfully.

-MSC2 beams back proper signal to MSC1, and announcement semihard handover success is finished.

-in MSC2 inside, signaling link and newly assigned control and treatment between it and the MS20 are partly coupled together.MSC2 sent a signaling link to MS20 immediately and resetted and indicate the second layer to the MS-MSC link this moment, to recover the consistency that signaling connects.MS20 is to its signal link context, together with MSC2, carries out initialization, with as the response that this reset operation is indicated.But this reset operation does not influence physics radio link layer (ground floor).Like this, common CDMA closed power control still can be carried out at MS20 with between as the BS12 that supports, and can any interruption not arranged because of semihard switches.In addition, it is also unaffected to relate to the signaling of call treatment (the 3rd layer).

After-MSC1 receives the announcement that semihard handover success that MSC2 transmits finishes, convert the uplink direction of link 32 uplink direction of new link 40 to, and the latter is connected with circuit on the link 42.After this operation is finished, the two-way communication full recovery of the user profile of MS20 and PSTN.MSC1 relates to release in the resource of this telex network, includes, but is not limited to: finish the facility that uplink users information frame diversity merges; The phonetic code conversion equipment that is used for voice communication; MS and BS signaling link terminal and control corresponding processing section.MSC1 also discharges the circuit that connects on the digital link 32 to BS12.MSC1 no longer relates to and calls out control like this, but still as the transit point of digital link 40 and 42, has finished semihard handoff procedure of the present invention like this.Consequently, the Radio Link controlled function has switched to MSC2 from MSC1, and does not interrupt the Radio Link between BS12 and MS20, and the closed power that does not particularly have to interrupt MS20 is controlled.By the operating in soft handover of MSC2 control, can in soft handover area SA2, carry out in the prior art, for example, when MS20 continues just can begin a soft handover from BS12 to BS14 when BS14 moves.

Like this, avoided the conventional CDMA direct-cut operation from MSC1 to MSC2, and corresponding reliability and the capacity that has improved system.

Fig. 3 illustrates the enforcement example of a MSC who is used for a cdma cellular communication system who the present invention relates to.

Digital link 120,122,124,126 are connected mobile switch MSC respectively with public switch telephone network PSTN, other mobile switch MSC, base station BS.

These digital links transmit user profile such as voice, also have signaling information in addition.The preferred embodiments of the present invention supposition signaling information and user profile are multiplexed in the same physical transfer equipment together.T1 transmission equipment and Signaling System 7(SS-7) can be used as the enforcement example of this digital link equipment together.

Utilize digital switch 112, user profile stream can exchange in aforementioned entity.Corresponding signaling information is transmitted by a packet exchanger 114, receives or relaying.Packet exchanger 114 also is connected on the MSC processor controls 110, this processor controls 110 can be respectively as the information source and the stay of two nights of signaling information.The signaling information that 110 pairs of MSC processor controls are issued it makes an explanation and reacts, and also in time sends demand signalling information to other entity.MSC processor controls 110 is gone the connection arrangement in the control figure interchanger 112 simultaneously according to call state.In addition, MSC processor controls 110 is in call setup or demolishing process, and code converter and combiner in corresponding resource storage portions the distributing equipment 100 perhaps discharge them.(a this equipment 100 that comprises code converter and combiner only is shown among the figure).

The equipment 100 that comprises code converter and combiner is used for following both conversion: the typical μ rule speech coding that promptly is used for PSTN; The low rate digitize voice coding that is used for Radio Link such as CELP.Except that the code conversion function, the equipment 100 that comprises code converter and combiner is also finished the signal diversifying merging of uplink direction and the signal replication of down link aspect.In addition, in the soft switching process that the binding signal diversity merges, the equipment 100 that comprises code converter and combiner is with following two kinds of information flows synchronously: a kind of information flow be from or be sent to and participate in the base station of communicating by letter, it is by digital link 124,126 transmission, by digital switch 112 exchanges, pass to the equipment 100 that comprises code converter and combiner by circuit 130,132; Another kind of information flow be from or be sent to PSTN, it is by digital link 120, digital switch 112 and circuit 134 transmit.(two BS of the branch diversity of only drawing among Fig. 2).

In a preferred embodiment of the invention, user communications signals comprises digitized voice signal or data, with be connected relevant signaling information with this together multiplexing, include digitized frame format in, this form is suitable for transmission on the terrestrial transmission link 124,126 between BS and MSC.Correspondingly, these frames are called as code converter/combiner frame, outside user profile, code converter/combiner frame also comprises the information relevant with signal quality that BS provides, and the signal diversifying on the uplink direction that these information are used for carrying out in the MSC merges.In addition, code converter/combiner frame also comprises the digital signal that BS and MSC provide.These signals, during the soft handover that the binding signal diversity merges, relevant with the synchronization of the synchronization link between BS and the MSC 124,126.

On the uplink and downlink link direction, respectively by circuit 130,132,134 import into or code converter/combiner frame of spreading out of all at 104 li buffer memorys of digital memory, digital processing unit 102 is the code converter/combiner frame in the read/write digital memory periodically.At uplink direction, the signal quality indication information via line 130,132 that is attached to code converter/combiner frame enters memory 104, and by checking these indication informations, according to these indications, processor 102 is carried out diversity and selected.In the down link direction, via line 134 enters the voice sampling of memory 104, carries out code conversion and assembling by processor 102, forms code converter/combiner frame.

By digital processing unit 102, comprise the equipment 100 of code converter and combiner, in code converter/combiner frame, extract or insertion subscriber signaling information, by circuit 140, provide or receive these subscriber signaling information to MSC processor controls 110.By this method, MSC processor controls 110 receives the MS signaling information, reports as the pilot signal quality measurement.MSC processor controls 110 has just obtained beginning or ends soft handover and semihard and has switched needed information like this.In addition, by this way, MSC processor controls 110 sends suitable switching command by circuit 140,130,132 and link 124,126 to MS, if necessary, can send these orders to other MSC by digital packet interchanger 114 and link 122.

Fig. 4 illustrates an enforcement example of the base station that relates to cdma cellular communication system of the present invention.

Module 200 expressions are supported the required device of single cdma communication in a base station, are called CDMA Channel equipment.Three similar Channel Elements 200A shown in Figure 4,200B, 200C.

According to the present invention, the base station is connected to mobile switch by digital link 232A and 232B respectively, for example MSC1 and MSC2.Between digital link 232A and 232B and Channel Elements 200, a digital switch 250 is arranged, it will from or be sent to Channel Elements 200A, 200B, the user profile of 200C stream exchanges between digital link 232A and 232B.This connection by digital switch 250 can be dynamic connection, and promptly it is once requiring, the circuit of instant exchange, and perhaps this exchange can be a kind of form of fast packet switching.In the preferred embodiments of the present invention, interchanger 250 belongs to the circuit types of instant exchange.Base station configuration shown in Fig. 4 is applicable to the base station 12 among Fig. 2, and base station 10 and 14 can be a similar configuration, but owing to only need a MSC link, digital switch 250 can save.

At uplink direction, the CDMA user communications signals that receives is from digital CDMA Radio Link 230, it is by 202 demodulation of CDMA demodulator, carry out deinterleaving and decoding by deinterleaving/decoder 206, for being used for terrestrial transmission, convert code converter/combiner frame to and be cached in digital memory 210, finally be transformed among selected digital link 232A and the 232B one, to MSC1 or MSC2 transmission by digital switch 250.

In the down link direction, by digital link 232A or 232B, receive code converter/combiner frame from MSC1 or MSC2, by digital switch 250 it is connected to Channel Elements 200A, 200B, among the 200C suitable one, buffer memory and convert the representation that is suitable for the base station in digital memory 210, and carry out chnnel coding by coding/interleaver 208, and carry out the CDMA modulation by CDMA modulator 204, finally send from digital radio link 230.

In the preferred embodiments of the present invention, BS has a clock source 220 that is independent of network, can provide effective CDMA operation required high accuracy reference signal, and be used for CDMA Channel equipment 200.This clock source can offer each BS in the global range from such as extracting the gps satellite signal, thereby sets up the BS network of phase mutually synchronization.

BS also comprises a BS processor controls 222, and BS control is in device 222 by being connected to digital link 232A and the 232B of MSC1 and MSC2, receives and send signaling information respectively.BS processor controls 222 is also carried out base station resource management, such as being used for distribution and the release that the user connects the CDMA Channel equipment of (calling).BS processor controls 222 will respond to the CDMA Channel request for allocation relevant with call setup, equally also to switching relevant CDMA Channel request for allocation with soft handover, semihard and respond from MSC.

At up link and downlink side upwards, digital processing unit 212 and buffer 210 together, the dismounting or the CDMA user communications signals of packing into and representing from code converter/synthesizer frame respectively with the BS internal form.In a preferred embodiment of the invention, also comprise the information that provides by deinterleaving/channel decoder 206 in aforementioned code transducer/synthesizer frame, this information offers digital processing unit 212, as the indication that receives the cdma wireless frame signal quality of coming from up cdma wireless link 230, and on uplink direction, the signal diversifying that is used in the MSC merges.

As mentioned above, the present invention relates to the switching between a kind of switch, be called the inter-exchange semihard and switch.Supposing that here these switch relevant MCS therewith, is for good and all or provisionally to link together by digital link, and the hand off signaling information between transmission user signal of communication and the MSC betwixt.

It must be understood that simultaneously method of the present invention can be applied to the TDMA cellular communication system at an easy rate.In a TDMA cellular communication system, Radio Link should be the TDMA Radio Link, and wherein time slot is used for providing communication channel to system user.In the soft handover that merges in conjunction with diversity, two (or more) time slots are used to provide parallel wireless channel, use for BS that relates to switching and MS.All other features of the present invention of mentioning remain unchanged in the TDMA cellular system.

The front description of preferred embodiments is to make or use the present invention with helping any those skilled in the art.For a person skilled in the art, the various modifications that these enforcement examples are done will be very tangible, and need not to use creativity, just the General Principle that defines can be applied to other herein and implement in example.Therefore, the present invention does not attempt to be limited to the enforcement example of enumerating, and should give and the corresponding to maximum magnitude of herein announcing as new feature of principle.

Claims (6)

1. cellular communication system, it comprises:

A plurality of mobile radio stations (MS20);

One first mobile switch (MSC1);

One second mobile switch (MSC2);

A plurality of base stations, first group (BS10) described a plurality of base stations, it only is connected with described first mobile switch (MSC1), second group (BS14) described a plurality of base stations, it only is connected with described second mobile switch (BSC2), having a base station at least is a border base station (BS12), is connected with second mobile switch with described first mobile switch simultaneously;

In described first mobile switch, to the equipment of a semihard switching of the described second mobile switch request;

In described second mobile switch, be used to distribute control and diversity to merge the equipment of resource, these resources are used for handling and control user profile by described second mobile switch;

In described at least one border base station, be used for from the equipment of described first mobile switch to the described second mobile switch converting users signal of communication;

In described second mobile switch, utilize the resource of being distributed to control the equipment of telex network;

In described second mobile switch, the equipment of relevant mobile radio station notice semihard switching in described a plurality of mobile radio stations;

In described second mobile switch, complete successfully the equipment that semihard switches to described first mobile switch announcement;

In described first mobile switch, discharge the equipment of the resource that relates to telex network.

2. according to the system of claim 1, it is characterized in that this system is a cdma system.

3. according to the system of claim 1, it is characterized in that this system is a tdma system.

4. semihard changing method that is used for cellular communication system, wherein said cellular communication system comprises:

A plurality of mobile radio stations;

One first mobile switch;

One second mobile switch;

A plurality of base stations, one through one group of described a plurality of base station, it only is connected with described first mobile switch, second group of described a plurality of base station, it only is connected with described second mobile switch, in described a plurality of base stations, having a base station at least is a border base station, is connected with second mobile switch with described first mobile switch simultaneously;

Described method is characterised in that, the control and the signal diversifying pooling function that relate to ongoing telex network, from described first mobile switch, switch to described second mobile switch, and do not interrupt relevant in a described a plurality of mobile radio station mobile radio station and the radio communication between described at least one border base station, the semihard switching comprises step:

Send the request that semihard switches by described first mobile switch to described second mobile switch;

Distribute described second mobile switch desired control and diversity to merge resource, to be used for handling and controlling described ongoing telex network;

On described at least one border base station, change described ongoing user communications signals to described second mobile switch from described first mobile switch;

Utilize the resource of described distribution, control described ongoing telex network by described second mobile switch;

Advise relevant in a station mobile radio station notice semihard to switch to described a plurality of moving;

Completing successfully semihard to described first mobile switch announcement switches;

In described first mobile switch, discharge the resource that relates to described ongoing telex network.

5. according to the method for claim 4, it is characterized in that the semihard switch application is in a cdma system.

6. want 4 method according to right, it is characterized in that, the semihard switch application is in a tdma system.

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