CN102256214A - Dynamic channel allocation method for comprehensive services and transmission characteristics of CDMA (Code Division Multiple Access) cluster system - Google Patents

Abstract

The invention relates to a dynamic channel allocation method for comprehensive services and transmission characteristics of a CDMA (Code Division Multiple Access) cluster system, in particular to a grading dynamic channel allocation method for a TD-SCDMA (Time Division-Synchronization Code Division Multiple Access) cluster system which is used for allocating resources according to the factors, such as channel state, service type, user priority, and the like in a digital cluster mobile communication system. According to the dynamic channel allocation method comprises, firstly, the services of the TD-SCDMA cluster system are classified and defined as follows: A. interactive mode and B. telemetering remote-control mode; and secondly, the related DCA (Dynamic Channel Allocation) of the TD-SCDMA cluster system comprises two basic processes, namely slow DCA process and quick DCA process, wherein the slow DCA process is used for allocating resources to the clusters by defining switching points of different application service types according to the application types of the TD-SCDMA cluster system; the slow DCA process is used for uplink resource allocation of the clusters; the quick DCA process is used for allocating physical channels to bearing services by dividing data, preserving time slots and defining changeable boundaries according to the service characteristics, the channel transmission characteristics and the service quality demands of cluster users of the TD-SCDMA cluster system; and the quick DCA process is used for downlink resource allocation of the cluster user.

Description

The dynamic channel assignment method of CDMA cluster system integrated service and transmission characteristic

Technical field

Trunking communication being by PTT signaling the seizing of power of conversing, and simultaneously the base station can obtain efficient resource occupation for this conversation distribution Uplink Shared Channel and DSCH Downlink Shared Channel, dynamic allocation of resources under limited system resource.The present invention relates generally to a kind of TD-SCDMA (Time Division-Synchronous Code Division Multiple synchronous CDMA (Code Division Multiple Access) of Access time-division) group system graduation dynamic channel allocation algorithm that in the Digital Clustering mobile communication system, carries out the resource size distribution according to factors such as channel status, type of service, User Priorities.

Background technology

China has determined that the frequency range that the Digital Clustering mobile communication is used is 800MHz in " Digital Clustering mobile communication system system ".Up-downgoing is respectively 806MHz-821MHz and 851MHz-866MHz, is total to 15MHz, and Duplex Spacing is 45MHz, and channel spacing is 25kHz.China is from April, 2003, and the professional commercial test of common network Digital Clustering is carried out in the part city at home.Wherein, former China Satcom has opened iDEN operation common network in Shanghai; The just logical company in Beijing builds TETRA and moves the government affairs common network in Beijing.The TETRA system has almost all been adopted in the communication of National urban light rail transit.The digital clustering communication system GoTa of China's independent research has built up a plurality of networks at home, and former China Railway Telecom is also in the Chongqing construction with opened GT800 system commercial test net.The current situation of China's digital cluster communication is compared with external developed regions and also is in initial stage, digital cluster system with national independent intellectual property right has also just begun development, no matter the market development from digital cluster communication still is a national industry development angle, all exist very big development space, this present situation is that to challenge also be opportunity for China's development of digital clustering communication system from now on.TD-SCDMA system based on the TDD technology, when carrying out PTT (putting call through immediately after connection) business, all technical capabilities that not only have 3G, the unique advantage that has other 3G especially and do not had: the asymmetric time slot allocation ability of the up-downgoing that TD-SCDMA possesses, can distribute the up-downgoing resource according to traffic carrying capacity, this group system to half-duplex operation is very useful.Simultaneously, TD-SCDMA wireless access technology as the 3GPP international standard, expand to digital cluster system on this basis with independent intellectual property right, both can further expand the application space and the inter-industry competition ability of TD-SCDMA technology, also meet Clustering developing direction and national interests development strategy fully.

The calling of mobile communication system all is point-to-point communication mode, a pair of signaling connects and Traffic Channel can satisfy conversation caller and called conversation demand as long as system sets up, and the Traffic Channel that system provides for the user all is the user's special use in conversing.And the calling of trunked communication system all is a point-to-multipoint mostly, and business believes and all share that at this moment the calling subscriber is one, and the called subscriber has a lot of, and everybody monitors a Traffic Channel, and the called subscriber is not distributed in the zone probably.This makes that system will signaling connects and the shared service channel for each zone be set up, simultaneously also will be according to the moving of group user, the zone of real-time service that change provides, group user to new region set up signaling connection and shared service channel.The mode of this shared channel of trunked communication system, than the mode of the dedicated channel of mobile communication, more complex, the organize content of related Radio Resource is also a lot of during change, need rethink the demarcation of a lot of resource allocation algorithms and parameter.The improvement of this algorithm and the demarcation of parameter also are processes of continuing to optimize, and also are the comparison time-consuming procedure.

The dynamic channel assignment method of TD SDMA group system integrated service characteristic

Summary of the invention

Technical problem: the present invention seeks on the basis of existing TD physical layer frame structure, to support group service, the technological difficulties that exist comprise: because the reverse link traffic channel and the downlink traffic channel of cluster all are sharing modes, up, a plurality of user time-sharing preemptive types are shared, descending, multi-user's (except that caller) shares simultaneously.This channel Mapping mode is different fully with the channel Mapping mode of common mobile communication, introduces unsteadiness easily.Moreover, because trunking communication is the half-duplex one-way channel, concerning hearer's (called), can't constitute the communication link of closed loop, also can't carry out the control of effective power, the system that makes can't the correct transmitting power of confirmation signal, obtains equilibrium at capacity with between covering.

According to analyzing the above problem that exists, the present invention distributes resource size by the factors such as channel status, type of service, User Priority of group users in the different groups are taken all factors into consideration, and designs the dynamic channel assignment method of the graduate TD SDMA group system integrated service characteristic of a kind of comprehensive customer service and transmission conditions.

Technical scheme: the invention provides a kind of TD-SCDMA group system graduation dynamic channel allocation algorithm that in the Digital Clustering mobile communication system, carries out the resource size distribution according to factors such as channel status, type of service, User Priorities.

At first, here Ding Yi term definition is as follows:

DCA: dynamic channel allocation

T _Ap: carry out the time of slow DCA again, can by on changing/frequency of downlink business adjusts

L: the timeslot number that frame is interior

L _d: descending link load

L _u: up link load

F (): according to the anticipation function to service traffics of single group user number, type of service design

: the uplink load average

NT _Ap: the current time of the DCA of group

(n-1) T _Ap: the previous moment of the DCA of group

γ: up-downgoing data service rate

t _j: j time slot in the frame

Ch _{I, j}: user i is at time slot t in the group _jLast corresponding physical channel

R _Voi: the transmission rate of voice service user i

C _{I, j}: service-user i is at ch _{I, j}On channel capacity

: service-user i is at channel ch _{I, j}The signaling channel noise ratio of last transmission

P _Ei: target packet loss or the bit error probability of service-user i

: the echo signal interchannel noise ratio that service-user i transmits on physical channel

C _i: the destination channel capacity that service-user i transmits on physical channel

: data user i is at channel ch _{I, j}The time delay of last transmission signals

T _Tari: data service user i is to the target call of time delay

α: the adjustment coefficient of service-user calculating priority level

β: the adjustment coefficient of service-user calculating priority level

A: the adjustment coefficient of data user's calculating priority level

B: the adjustment coefficient of data user's calculating priority level

C: the adjustment coefficient of data user's calculating priority level

N: n Ta _pTime, i.e. n time of carrying out slow DCA again

N _Tu: the uplink service timeslot number

N _Td: the downlink business timeslot number

Min (): in the variable set, get the expression formula that makes in the bracket and be minimum variate-value

At first, the business of TD-SCDMA group system is classified, TD-SCDMA group system type of service is defined as: the A interactive mode comprises digital dispatching, data query and transaction application; B remote measuring and controlling formula; C broadcast type three classes; Interactive provisional capital up and down needs allocation of channel resources may; The remote measuring and controlling formula need be distributed uplink channel resources; Broadcast type needs the allocation of downlink resource;

Secondly, related TD-SCDMA group system dynamic channel allocation DCA comprises two basic processes, promptly slow DCA and fast DCA; Slow DCA is the application type according to the TD-SCDMA group system, by the switching point of definition different application type of service, gives group with resource allocation, is used for the uplink resource allocation of group; Fast DCA is business characteristic, channel transfer characteristic, the quality of services for users requirement according to the TD-SCDMA cluster user, by dividing speech, data, reservation time slot and definition variable boundary, physical channel is distributed to bearer service, be used for the uplink resource allocation of group user.

Described slow DCA: for adapting to the variation of cluster communication service rate, system at first carries out slow DCA, every T _ApTime is adjusted the number of timeslots in the Uplink/Downlink; Obtain service parameter, judge that according to service parameter which kind of in A interactive mode, B remote measuring and controlling formula, the C broadcast type be the type of service of group system be;

In the A interactive application, the downlink broadcast channel is shared by all groups, only has the user of call request to initiate request in the uplink communication, need allocation of channel resources may, 6 business time-slots are only arranged, therefore in the TD-SCDMA system, up-downgoing traffic assignments rate choosing value is 2: 4,3: 3, and 4: 2; Consider the characteristics of group system, descending link load L _dBe known, the uplink load of each group is estimated by following formula:

${\stackrel{\‾}{L}}_u\left({\mathrm{nT}}_{\mathrm{ap}}\right)=f\left({\stackrel{\‾}{L}}_u\left((n-1)T_{\mathrm{ap}}\right)\right)$

Wherein, function f () is the anticipation function to service traffics according to single group user number, type of service design, that is, and and the current time nT of group _ApUplink load be according to its previous moment (n-1) T _ApAnd the estimation average that obtains of historical record empirical mean, according to the current time of estimating

Can calculate up-downgoing data service rate γ, n is the number of Tap time, i.e. n time of carrying out slow DCA again, therefore have

$\mathrm{\γ}={\stackrel{\‾}{L}}_u/L_d$

At last, according to minimizing

Principle find only uplink and downlink timeslot allocative decision, be expressed as following formula:

$(N_{\mathrm{tu}},N_{\mathrm{td}})=\underset{(N_{\mathrm{tu}}:N_{\mathrm{td}})=\left\{(2:4),(3:3),(4:2)\right\}}{\min }\left(|\mathrm{\γ}-\frac{N_{\mathrm{tu}}}{N_{\mathrm{td}}}|\right)$

In the formula, γ is a up-downgoing data service rate, N _TuBe uplink service timeslot number, N _TdBe the downlink business timeslot number, function m in () is at (N _Tu: N _Td) get in the set and make expression formula

(N for minimum _Tu: N _Td) value;

In B remote measuring and controlling formula was used, the transmission data from group user only need be collected and monitor to control desk, and therefore, in slow DCA, up-downgoing traffic assignments rate choosing value is 4: 2;

In the C broadcast type was used, control desk only was sent to message the geographic area of qualification, needn't confirm that message was retransmitted several times in a period of time, and to increase the reliability that receives, therefore, in slow DCA, up-downgoing traffic assignments rate choosing value is 2: 4.

Described slow DCA, its flow process is: as time variable t＜T _ApThe time, carry out slow DCA process, at first obtain service parameter, according to according to a preliminary estimate to service parameter, carry out application type and judge, determine current group system is to be in which kind of application, when decision-making system is in a certain class and uses, slow DCA is cut corresponding flow process, be that category-A is used if judge, enter the slow DCA flow process of category-A,, enter the slow DCA flow process of category-B if judge it is that category-B is used, if judge it is that the C class is used, enter the slow DCA flow process of C class, when having assigned, finish slow DCA, and wait for next T _ApTime.

Described fast DCA: in fast DCA, only the up channel distribution at category-A and category-B application designs, adopt the dynamic assignment of variable boundary strategy realization to channel resource, by defining two variable boundaries, three kinds of different priority criteria are distributed up channel;

Two variable boundaries: the time slot in the frame is divided according to speech, data and reservation type of service, first variable boundary is used for defining voice and reserves professional, second variable boundary is used for defining to be reserved and data service, and the definition on two borders is to determine according to the empirical value of customer service estimation in the past in the group equally;

Three kinds of different priority criteria comprise the voice user priority criteria:

The user who is both voice service determines its priority factor according to uplink physical channel transmission conditions, user's qos parameter, and time slot is at war with, and supposes that voice service user i is at j time slot t in the group _j, j=1,2 ..., the last corresponding physical channel of L is ch _{I, j}, the transmission rate of voice service user i is R _Voi, at ch _{I, j}On channel capacity be C _{I, j}, at channel ch _{I, j}The signaling channel noise ratio of last transmission is The target packet loss of voice service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio that transmits on physical channel is

Corresponding channel capacity is C _i, and

$C_{i,j}=R_{\mathrm{voi}}\log (1+{\mathrm{\γ}}_{{\mathrm{ch}}_{i,j}})$

Definition priority factor f _{I, j}As follows:

f _i，j＝α|C _i，j-C _i|+β|γ _i，j-γ _i|

Wherein, α and β be for adjusting coefficient, is the empirical value that carries out match according to data in the past;

Data user's priority criteria: the user who is both data service is at war with to time slot according to uplink physical channel transmission conditions, user's qos parameter, time of delay determining its priority factor, and tentation data service-user i is at time slot t _j, j=1,2 ..., the last corresponding physical channel of L is ch _{I, j}, the transmission rate of data service user i is R _Dati, at ch _{I, j}On channel capacity be C _{I, j}, at channel ch _{I, j}The signaling channel noise ratio of last transmission is

At channel ch _{I, j}The time delay of last transmission signals is

The target packet loss of data service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio that transmits on physical channel is

Corresponding channel capacity is C _i, the time delay of data service user i requires to be T _Tari, and

$C_{i,j}=R_{\mathrm{dati}}\log (1+{\mathrm{\γ}}_{{\mathrm{ch}}_{i,j}})$

Definition priority factor f _{I, j}As follows:

$f_{i,j}=a|C_{i,j}-C_i|+b|{\mathrm{\γ}}_{i,j}-{\mathrm{\γ}}_i|+c|T_{{\mathrm{tar}}_{i,j}}-T_{\mathrm{tari}}|$

Wherein, a, b and c be for adjusting coefficient, is the empirical value that carries out match according to data in the past;

Reserve the time slot priority criteria: the priority of voice service is higher than data service all the time, and when voice service was seized the reservation time slot, the priority height overall was in data service.When not having the speech business conversion to reserve time slot, data service is used and is reserved time slot.

Described fast DCA, its flow process is: at first the base station obtains the service parameter of up user applies channel resource, judges that according to parameter uplink service is speech or data; If voice service, check at first whether the speech time slot is full, if the speech time slot does not take, enter voice service priority criteria program and calculate current application user's distribution priority, other voice service User Priority of the request resource of the priority that calculates and synchronization is compared, carry out the distribution of speech time slot according to priority; If the speech time slot takes, then enter the time slot competition of reserving time slot, according to reserving time slot priority criteria program calculating priority level, and carry out time slot allocation by the priority factor that calculates, judge whether reserve time slot takes, if it is full to reserve time slot, apply for that then the user enters service queue, this time slot allocation finishes; If reserve time slot less than, apply for that then the user accepts to distribute indication; If judge that the user is data service, check then whether data slot is full, if data slot does not take, enter data service priority criteria program and calculate current application user's distribution priority, other data service User Priority of the request resource of the priority that calculates and synchronization is compared, carry out the distribution of speech time slot according to priority; If the speech time slot takes, then enter the time slot competition of reserving time slot, according to reserving time slot priority criteria program calculating priority level, and carry out time slot allocation by the priority factor that calculates, judge whether reserve time slot takes, if it is full to reserve time slot, apply for that then the user enters service queue, this time slot allocation finishes; If reserve time slot less than, apply for that then the user accepts to distribute indication.

Beneficial effect: the invention provides a kind of TD-SCDMA group system graduation dynamic channel allocation algorithm that in the Digital Clustering mobile communication system, carries out the resource size distribution according to factors such as channel status, type of service, User Priorities.

Achievement of the present invention belongs to autonomous innovation, Own Brand, independent intellectual property right, has international most advanced level.To fill the domestic gaps, break international monopoly, promote domestic Digital Clustering technological progress, promote the competitiveness of China's mobile communication industry, and help every profession and trade to enhance productivity, quicken development and national economy and industrial upgrading in the international market.

The invention enables the TD-SCDMA system to support the demand of trunking communication on the original basis, between multiple business, realize resource-sharing, improve resource utilization, obtain higher band efficiency.

Description of drawings

By below in conjunction with the accompanying drawing and the detailed description of carrying out, it is clearer that above and other objects of the present invention, characteristics and advantage will become, wherein;

Fig. 1 shows at group system three classes and uses the slow DCA time slot allocation diagrammatic sketch that carries out.

Fig. 2 shows the operational flowchart that group system is carried out slow DCA time slot allocation.

Fig. 3 shows the fast DCA time slot allocation diagrammatic sketch that carries out at group system two class types of service.

Fig. 4 shows the operational flowchart that group system is carried out fast DCA time slot allocation.

Embodiment

1, TD-SCDMA group system type of service:

The application of group system business can be classified as three classes: broadcasted application, transaction are used and interactive application.Broadcasted application comprises general messenger service, situation announcement and advertisement.In broadcasted application, only message is sent to the geographic area of qualification, needn't confirm.Message can be retransmitted several times in a period of time, to increase the reliability that receives.Transaction is used and is made up of two message usually, and one is solicit operation, and another is to confirm whether this operation is successful, and two message are finished the primary information exchange.Some affairs may comprise repeatedly information exchange, delivers as Card Verification, paging, voice mailbox notice, email notification and Email.Interactive application need and provide between the professional dispatching desk computer at travelling carriage carries out repeatedly message, comprises that terminal inserts main frame, database inserts and remote lan inserts.Mobile data services can be applicable to public safety, administration, communications and transportation and many industrial circles, and mobile data user's fundamental type can be divided into five big classes: digital dispatching, data query, remote measuring and controlling, browse and issue.

According to above classification, in the present invention TD-SCDMA group system type of service is defined as: interactive mode comprises digital dispatching, data query and transaction application; The remote measuring and controlling formula; Broadcast type three classes.Interactive provisional capital up and down needs allocation of channel resources may; The remote measuring and controlling formula need be distributed uplink channel resources; Broadcast type needs the allocation of downlink resource.

2, TD-SCDMA group system DCA process involved in the present invention:

TD-SCDMA group system DCA involved in the present invention comprises two basic processes, promptly slow DCA and fast DCA.Slow DCA gives group with resource allocation, is used for the uplink resource allocation of group; Fast DCA distributes to bearer service with physical channel, is used for the uplink resource allocation of group user.Below will specify algorithm and the flow process of slow DCA and fast DCA.

2.1 slow DCA

For adapting to the variation of cluster communication service rate, system at first carries out slow DCA, every T _ApTime is adjusted the number of timeslots in the Uplink/Downlink.At first, obtain service parameter, judge that according to service parameter which kind of in A interactive mode, B remote measuring and controlling formula, the C broadcast type be the type of service of group system be;

In category-A was used, the downlink broadcast channel was shared by all groups, only had the user of call request to initiate request in the uplink communication, needed allocation of channel resources may.6 business time-slots are only arranged in the TD-SCDMA system, and therefore, the optional value of up-downgoing traffic assignments rate is 2: 4,3: 3, and 4: 2.Consider the characteristics of group system, descending link load L _dBe known, the uplink load of each group can be estimated by following formula:

${\stackrel{\‾}{L}}_u\left({\mathrm{nT}}_{\mathrm{ap}}\right)=f\left({\stackrel{\‾}{L}}_u\left((n-1)T_{\mathrm{ap}}\right)\right)$

Wherein, function f () is the anticipation function to service traffics according to single group user number, type of service design, that is, and and the current time nT of group _ApUplink load be according to its previous moment (n-1) T _ApAnd the estimation average that obtains of historical record empirical mean.According to the current time of estimating

Can calculate up-downgoing data service rate γ, promptly

$\mathrm{\γ}={\stackrel{\‾}{L}}_u/L_d$

At last, according to minimizing

Principle find only uplink and downlink timeslot allocative decision, be expressed as following formula:

$(N_{\mathrm{tu}},N_{\mathrm{td}})=\underset{(N_{\mathrm{tu}}:N_{\mathrm{td}})=\left\{(2:4),(3:3),(4:2)\right\}}{\min }\left(|\mathrm{\γ}-\frac{N_{\mathrm{tu}}}{N_{\mathrm{td}}}|\right)$

In category-B was used, the transmission data from group user only need be collected and monitor to control desk, and therefore, in slow DCA, the optional value of up-downgoing traffic assignments rate is 4: 2.

In the C class was used, control desk only was sent to message the geographic area of qualification, needn't confirm.Message can be retransmitted several times in a period of time, to increase the reliability that receives.Therefore, in slow DCA, the optional value of up-downgoing traffic assignments rate is 2: 4.

2.2 fast DCA

In fast DCA, the present invention only designs at the up channel distribution of category-A and category-B application.Adopt the dynamic assignment of variable boundary strategy realization to channel resource.By defining two variable boundaries, three kinds of different priority criteria are distributed up channel.

Two variable boundaries: the time slot in the frame is divided according to speech, data and reservation type of service.First variable boundary is used for defining voice and reserves business, and second variable boundary is used for defining to be reserved and data service.The definition on two borders is to determine according to the empirical value of customer service estimation in the past in the group equally.

Three kinds of different priority criteria:

1) voice user priority criteria

The user who is both voice service determines its priority factor according to uplink physical channel transmission conditions, user's qos parameter, and time slot is at war with, and supposes that voice service user i is at time slot t in the group _j, j=1,2 ..., the last corresponding physical channel of L is ch _{I, j}, the transmission rate of voice service user i is R _Voi, at ch _{I, j}On channel capacity be C _{I, j}, at channel ch _{I, j}The signaling channel noise ratio of last transmission is

Voice service is P with target packet loss or the bit error probability of i _Ei, the corresponding echo signal interchannel noise ratio that transmits on physical channel is Corresponding channel capacity is C _i, and

$C_{i,j}=R_{\mathrm{voi}}\log (1+{\mathrm{\γ}}_{{\mathrm{ch}}_{i,j}})$

Definition priority factor f _{I, j}As follows:

f _i，j＝α|C _i，j-C _i|+β|γ _i，j-γ _i|

Wherein, α and β be for adjusting coefficient, is the empirical value that carries out match according to data in the past.

2) data user's priority criteria

The user who is both data service is at war with to time slot according to uplink physical channel transmission conditions, user's qos parameter, time of delay determining its priority factor, and tentation data service-user i is at time slot t _j, j=1,2 ..., the last corresponding physical channel of L is ch _{I, j}, the transmission rate of data service user i is R _Dati, at ch _{I, j}On channel capacity be C _{I, j}, at channel ch _{I, j}The signaling channel noise ratio of last transmission is

At channel ch _{I, j}The time delay of last transmission signals is

The target packet loss of data service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio that transmits on physical channel is

Corresponding channel capacity is C _i, the time delay of data service user i requires to be T _Tari, and

$C_{i,j}=R_{\mathrm{dati}}\log (1+{\mathrm{\γ}}_{{\mathrm{ch}}_{i,j}})$

Definition priority factor f _{I, j}As follows:

$f_{i,j}=a|C_{i,j}-C_i|+b|{\mathrm{\γ}}_{i,j}-{\mathrm{\γ}}_i|+c|T_{{\mathrm{tar}}_{i,j}}-T_{\mathrm{tari}}|$

Wherein, a, b and c be for adjusting coefficient, is the empirical value that carries out match according to data in the past.

3) reserve the time slot priority criteria

The priority of voice service is higher than data service all the time, and when voice service was seized the reservation time slot, the priority height overall was in data service.When not having the speech business conversion to reserve time slot, data service can be used the reservation time slot.

Preferential embodiment of the present invention is here described below with reference to accompanying drawings.Because known function and structure make the present invention fuzzy in unnecessary details, therefore they are described no longer in the following description.

Before describing the present invention, term definition used herein is as follows:

Three class application types: refer to A interactive mode, B remote measuring and controlling formula, three kinds of cluster application of C broadcast type.

Type of service: refer to speech and data two class types of service.

A. slow DCA

Fig. 1 shows at group system three classes and uses the slow DCA time slot allocation diagrammatic sketch that carries out.

With reference to Fig. 1, show in a 5ms subframe time slot allocation situation at the slow DCA of different cluster application.In assigning process, there are two switching points, switching point A and switching point B, switching point A .... fix, for category-A is used (step 102), switching point B carries out dynamic channel allocation according to up-downgoing traffic carrying capacity ratio, at first calculates the up average traffic load of current time

${\stackrel{\‾}{L}}_u\left({\mathrm{nT}}_{\mathrm{ap}}\right)=f\left({\stackrel{\‾}{L}}_u\left((n-1)T_{\mathrm{ap}}\right)\right)$

Wherein, function f () is the anticipation function to service traffics according to single group user number, type of service design, that is, and and the current time nT of group _ApUplink load be according to its previous moment (n-1) T _ApAnd the estimation average that obtains of historical record empirical mean.According to the current time of estimating

Can calculate up-downgoing data service rate γ, promptly

$\mathrm{\γ}={\stackrel{\‾}{L}}_u/L_d$

At last, according to minimizing

Principle find only uplink and downlink timeslot allocative decision, be expressed as following formula:

$(N_{\mathrm{tu}},N_{\mathrm{td}})=\underset{(N_{\mathrm{tu}}:N_{\mathrm{td}})=\left\{(2:4),(3:3),(4:2)\right\}}{\min }\left(|\mathrm{\γ}-\frac{N_{\mathrm{tu}}}{N_{\mathrm{td}}}|\right)$

For category-B is used (step 104), the transmission data from group user only need be collected and monitor to control desk, and therefore, in slow DCA, the optional value of up-downgoing traffic assignments rate is 4: 2.

For the C class is used (step 106), control desk only is sent to message the geographic area of qualification, needn't confirm.Message can be retransmitted several times in a period of time, to increase the reliability that receives.Therefore, in slow DCA, the optional value of up-downgoing traffic assignments rate is 2: 4.

Fig. 2 shows the operational flowchart that group system is carried out slow DCA time slot allocation.

With reference to Fig. 2, as time t＜T _ApThe time, carry out slow DCA process.At first obtain service parameter (step 210),, carry out application type and judge (step 212), determine current group system is to be in which kind of application (step 214) according to according to a preliminary estimate to service parameter.When decision-making system is in a certain class and uses, slow DCA is cut corresponding flow process, if judge it is that category-A is used, enter the slow DCA flow process of category-A (step 216), be that category-B is used if judge, enter the slow DCA flow process of category-B (step 216), if judge it is that the C class is used, enter the slow DCA flow process of C class (step 216), when having assigned, finish slow DCA (step 218), and wait for next T _ApTime.

B. fast DCA

Fig. 3 shows at group system three classes and uses the fast DCA time slot allocation diagrammatic sketch that carries out.

With reference to Fig. 3, in a frame length that comprises L time slot, time slot is divided three class time slot sections by movable border A and movable boundary B: segment of speech (302), data segment (304) and reserve section (306).Variable boundary A is used for defining voice and reserves business, and variable boundary B is used for defining and reserves and data service.The definition on two borders is determined according to the empirical value of customer service traffic carrying capacity estimation in the past in the group.Define different User Priority criterions respectively in three class time slot sections.

1, voice user priority criteria (308) definition procedure is:

The user who is both voice service determines its priority factor according to uplink physical channel transmission conditions, user's qos parameter, and time slot is at war with, and supposes that voice service user i is at time slot t in the group _j, j=1,2 ..., the last corresponding physical channel of L is ch _{I, j}, the transmission rate of voice service user i is R _Voi, at ch _{I, j}On channel capacity be C _{I, j}, at channel ch _{I, j}The signaling channel noise ratio of last transmission is

The target packet loss of voice service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio that transmits on physical channel is

Corresponding channel capacity is C _i, and

$C_{i,j}=R_{\mathrm{voi}}\log (1+{\mathrm{\γ}}_{{\mathrm{ch}}_{i,j}})$

Definition priority factor f _{I, j}As follows:

f _i，j＝α|C _i，j-C _i|+β|γ _i，j-γ _i|

Wherein, α and β be for adjusting coefficient, is the empirical value that carries out match according to data in the past.

2, data user's priority criteria (310) definition procedure is:

The user who is both data service is at war with to time slot according to uplink physical channel transmission conditions, user's qos parameter, time of delay determining its priority factor, and tentation data service-user i is at time slot t _j, j=1,2 ..., the last corresponding physical channel of L is ch _{I, j}, the transmission rate of data service user i is R _Dati, at ch _{I, j}On channel capacity be C _{I, j}, at channel ch _{I, j}The signaling channel noise ratio of last transmission is

At channel ch _{I, j}The time delay of last transmission signals is

The target packet loss of data service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio that transmits on physical channel is

Corresponding channel capacity is C _i, the time delay of data service user i requires to be T _Tari, and

$C_{i,j}=R_{\mathrm{dati}}\log (1+{\mathrm{\γ}}_{{\mathrm{ch}}_{i,j}})$

Definition priority factor f _{I, j}As follows:

$f_{i,j}=a|C_{i,j}-C_i|+b|{\mathrm{\γ}}_{i,j}-{\mathrm{\γ}}_i|+c|T_{{\mathrm{tar}}_{i,j}}-T_{\mathrm{tari}}|$

Wherein, a, b and c be for adjusting coefficient, is the empirical value that carries out match according to data in the past.

3, reserving section User Priority criterion (312) definition procedure is:

The priority of voice service is higher than data service all the time, and when voice service was seized the reservation time slot, the priority height overall was in data service.When not having the speech business conversion to reserve time slot, data service can be used the reservation time slot.

Fig. 4 shows the operational flowchart that group system is carried out fast DCA time slot allocation.

With reference to Fig. 4, at first the base station obtains the service parameter (step 410) of up user applies channel resource, judges that according to parameter uplink service is speech or data (step 412).If voice service, at first check speech time slot whether full (step 414), if the speech time slot does not take, enter voice service priority criteria program and calculate current application user's distribution priority (step 416), other voice service User Priority of the request resource of the priority that calculates and synchronization is compared, carry out the distribution (step 418) of speech time slot according to priority.If the speech time slot takes, then enter the time slot competition of reserving time slot, according to reserving time slot priority criteria program calculating priority level (step 420), and carry out time slot allocation (step 422) by the priority factor that calculates, judge whether reserve time slot has taken (step 424), if it is full to reserve time slot, apply for that then the user enters service queue, this time slot allocation finishes (step 426).If reserve time slot less than, apply for that then the user accepts to distribute indication (step 434).If judge that in step 412 user is data service, then check data slot whether full (step 428), if data slot does not take, enter data service priority criteria program and calculate current application user's distribution priority (step 430), other data service User Priority of the request resource of the priority that calculates and synchronization is compared, carry out the distribution (step 432) of speech time slot according to priority.If the speech time slot takes, then enter the time slot competition of reserving time slot, according to reserving time slot priority criteria program calculating priority level (step 420), and carry out time slot allocation (step 422) by the priority factor that calculates, judge whether reserve time slot has taken (step 424), if it is full to reserve time slot, apply for that then the user enters service queue, this time slot allocation finishes (step 426).If reserve time slot less than, apply for that then the user accepts to distribute indication (step 434).

Claims (5)

1. the dynamic channel assignment method of a TD SDMA group system integrated service characteristic is characterized in that this dynamic channel assignment method is specific as follows:

At first, the business of TD-SCDMA group system is classified, TD-SCDMA group system type of service is defined as: the A interactive mode comprises digital dispatching, data query and transaction application; B remote measuring and controlling formula; C broadcast type three classes; Interactive provisional capital up and down needs allocation of channel resources may; The remote measuring and controlling formula need be distributed uplink channel resources; Broadcast type needs the allocation of downlink resource;

Secondly, related TD-SCDMA group system dynamic channel allocation DCA comprises two basic processes, promptly slow DCA and fast DCA; Slow DCA is the application type according to the TD-SCDMA group system, by the switching point of definition different application type of service, gives group with resource allocation, is used for the uplink resource allocation of group; Fast DCA is business characteristic, channel transfer characteristic, the quality of services for users requirement according to the TD-SCDMA cluster user, by dividing speech, data, reservation time slot and definition variable boundary, physical channel is distributed to bearer service, be used for the uplink resource allocation of group user.

2. the dynamic channel assignment method of TD SDMA group system integrated service characteristic according to claim 1 is characterized in that described slow DCA: for adapting to the variation of cluster communication service rate, system at first carries out slow DCA, every T _ApTime is adjusted the number of timeslots in the Uplink/Downlink; Obtain service parameter, judge that according to service parameter which kind of in A interactive mode, B remote measuring and controlling formula, the C broadcast type be the type of service of group system be;

In the A interactive application, the downlink broadcast channel is shared by all groups, only has the user of call request to initiate request in the uplink communication, need allocation of channel resources may, 6 business time-slots are only arranged, therefore in the TD-SCDMA system, up-downgoing traffic assignments rate choosing value is 2: 4,3: 3, and 4: 2; Consider the characteristics of group system, descending link load L _dBe known, the uplink load of each group is estimated by following formula:

${\stackrel{\‾}{L}}_u\left({\mathrm{nT}}_{\mathrm{ap}}\right)=f\left({\stackrel{\‾}{L}}_u\left((n-1)T_{\mathrm{ap}}\right)\right)$

Wherein, function f () is the anticipation function to service traffics according to single group user number, type of service design, that is, and and the current time nT of group _ApUplink load be according to its previous moment (n-1) T _ApAnd the estimation average that obtains of historical record empirical mean, according to the current time of estimating

Can calculate up-downgoing data service rate γ, n is the number of Tap time, i.e. n time of carrying out slow DCA again, therefore have

$\mathrm{\γ}={\stackrel{\‾}{L}}_u/L_d$

At last, according to minimizing

Principle find only uplink and downlink timeslot allocative decision, be expressed as following formula:

$(N_{\mathrm{tu}},N_{\mathrm{td}})=\underset{(N_{\mathrm{tu}}:N_{\mathrm{td}})=\left\{(2:4),(3:3),(4:2)\right\}}{\min }\left(|\mathrm{\γ}-\frac{N_{\mathrm{tu}}}{N_{\mathrm{td}}}|\right)$

In the formula, γ is a up-downgoing data service rate, N _TdBe uplink service timeslot number, N _TdBe the downlink business timeslot number, function m in () is at (N _Tu: N _Td) get in the set and make expression formula

(N for minimum _Tu: N _Td) value;

In B remote measuring and controlling formula was used, the transmission data from group user only need be collected and monitor to control desk, and therefore, in slow DCA, up-downgoing traffic assignments rate choosing value is 4: 2;

In the C broadcast type was used, control desk only was sent to message the geographic area of qualification, needn't confirm that message was retransmitted several times in a period of time, and to increase the reliability that receives, therefore, in slow DCA, up-downgoing traffic assignments rate choosing value is 2: 4.

3. the dynamic channel assignment method of TD SDMA group system integrated service characteristic according to claim 2 is characterized in that described slow DCA, and its flow process is: as time variable t＜T _ApThe time, carry out slow DCA process, at first obtain service parameter, according to according to a preliminary estimate to service parameter, carry out application type and judge, determine current group system is to be in which kind of application, when decision-making system is in a certain class and uses, slow DCA is cut corresponding flow process, be that category-A is used if judge, enter the slow DCA flow process of category-A,, enter the slow DCA flow process of category-B if judge it is that category-B is used, if judge it is that the C class is used, enter the slow DCA flow process of C class, when having assigned, finish slow DCA, and wait for next T _ApTime.

4. the dynamic channel assignment method of TD SDMA group system integrated service characteristic according to claim 1, it is characterized in that described fast DCA: in fast DCA, only the up channel distribution at category-A and category-B application designs, adopt the dynamic assignment of variable boundary strategy realization to channel resource, by defining two variable boundaries, three kinds of different priority criteria are distributed up channel;

Two variable boundaries: the time slot in the frame is divided according to speech, data and reservation type of service, first variable boundary is used for defining voice and reserves professional, second variable boundary is used for defining to be reserved and data service, and the definition on two borders is to determine according to the empirical value of customer service estimation in the past in the group equally;

Three kinds of different priority criteria comprise the voice user priority criteria:

The user who is both voice service determines its priority factor according to uplink physical channel transmission conditions, user's qos parameter, and time slot is at war with, and supposes that voice service user i is at j time slot t in the group _j, j=1,2 ..., the last corresponding physical channel of L is ch _{I, j}, the transmission rate of voice service user i is R _Voi, at ch _{I, j}On channel capacity be C _{I, j}, at channel ch _{I, j}The signaling channel noise ratio of last transmission is

The target packet loss of voice service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio that transmits on physical channel is

Corresponding channel capacity is C _i, and

$C_{i,j}=R_{\mathrm{voi}}\log (1+{\mathrm{\γ}}_{{\mathrm{ch}}_{i,j}})$

Definition priority factor f _{I, j}As follows:

f _i，j＝α|C _i，j-C _i|+β|γ _i，j-γ _i|

Wherein, α and β be for adjusting coefficient, is the empirical value that carries out match according to data in the past;

Data user's priority criteria: the user who is both data service is at war with to time slot according to uplink physical channel transmission conditions, user's qos parameter, time of delay determining its priority factor, and tentation data service-user i is at time slot t _j, j=1,2 ..., the last corresponding physical channel of L is ch _{I, j}, the transmission rate of data service user i is R _Dati, at ch _{I, j}On channel capacity be C _{I, j}, at channel ch _{I, j}The signaling channel noise ratio of last transmission is

At channel ch _{I, j}The time delay of last transmission signals is The target packet loss of data service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio that transmits on physical channel is

Corresponding channel capacity is C _i, the time delay of data service user i requires to be T _Tari, and

$C_{i,j}=R_{\mathrm{dati}}\log (1+{\mathrm{\γ}}_{{\mathrm{ch}}_{i,j}})$

Definition priority factor f _{I, j}As follows

$f_{i,j}=a|C_{i,j}-C_i|+b|{\mathrm{\γ}}_{i,j}-{\mathrm{\γ}}_i|+c|T_{{\mathrm{tar}}_{i,j}}-T_{\mathrm{tari}}|$

Wherein, a, b and c be for adjusting coefficient, is the empirical value that carries out match according to data in the past;

Reserve the time slot priority criteria: the priority of voice service is higher than data service all the time, and when voice service was seized the reservation time slot, the priority height overall was in data service.When not having the speech business conversion to reserve time slot, data service is used and is reserved time slot.

5. the dynamic channel assignment method of TD SDMA group system integrated service characteristic according to claim 1, it is characterized in that described fast DCA, its flow process is: at first the base station obtains the service parameter of up user applies channel resource, judges that according to parameter uplink service is speech or data; If voice service, check at first whether the speech time slot is full, if the speech time slot does not take, enter voice service priority criteria program and calculate current application user's distribution priority, other voice service User Priority of the request resource of the priority that calculates and synchronization is compared, carry out the distribution of speech time slot according to priority; If the speech time slot takes, then enter the time slot competition of reserving time slot, according to reserving time slot priority criteria program calculating priority level, and carry out time slot allocation by the priority factor that calculates, judge whether reserve time slot takes, if it is full to reserve time slot, apply for that then the user enters service queue, this time slot allocation finishes; If reserve time slot less than, apply for that then the user accepts to distribute indication; If judge that the user is data service, check then whether data slot is full, if data slot does not take, enter data service priority criteria program and calculate current application user's distribution priority, other data service User Priority of the request resource of the priority that calculates and synchronization is compared, carry out the distribution of speech time slot according to priority; If the speech time slot takes, then enter the time slot competition of reserving time slot, according to reserving time slot priority criteria program calculating priority level, and carry out time slot allocation by the priority factor that calculates, judge whether reserve time slot takes, if it is full to reserve time slot, apply for that then the user enters service queue, this time slot allocation finishes; If reserve time slot less than, apply for that then the user accepts to distribute indication.

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