CN102256214B - 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 base station, for the dynamic assignment of this conversation distribution Uplink Shared Channel and DSCH Downlink Shared Channel, resource, can obtain efficient resource occupation 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 carries out the resource size distribution in the Digital Clustering mobile communication system according to factors such as channel status, type of service, User Priorities.

Background technology

China, in " Digital Clustering mobile communication system system ", has determined that the frequency range that the Digital Clustering mobile communication is used is 800MHz.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 urban carries out common network Digital Clustering business commercial test at home.Wherein, former China Satcom has opened iDEN operation common network in Shanghai; Beijing Zheng Tong company builds TETRA mobile government common network in Beijing.The communication of National urban light rail transit, almost all adopted the TETRA system.The digital clustering communication system GoTa of China's independent research is built 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 also in initial stage with external developed regions, digital cluster system with national independent intellectual property right has also just started development, no matter from market development or the national industry of digital cluster communication, develop angle, all exist very large development space, this present situation is that to challenge be also 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, the all technical capabilities that not only there is 3G, the unique advantage that there is 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, to the digital cluster system with independent intellectual property right, expand on this basis, both can further expand 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, be all point-to-point communication mode, as long as system is set up, a pair of signaling connects and Traffic Channel can meet conversation caller and called conversation demand, and the Traffic Channel that system provides for the user is all user's special use in conversing.And the calling of trunked communication system is mostly all point-to-multipoint, business believes and all shares, and 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 probably is not distributed in a zone.This makes, and system will for each zone be set up, signaling connects and the shared service channel, simultaneously also will be according to group user's movement, 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, during change, the organize content of related Radio Resource is also a lot, need to rethink the demarcation of a lot of resource allocation algorithms and parameter.The improvement of this algorithm and the demarcation of parameter, be also a process of continuing to optimize, and is also process more consuming time.

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

Summary of the invention

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

According to analyzing the above problem existed, the present invention is considered resource size is distributed by factors such as the channel status to group user in different groups, type of service, User Priorities, designs the dynamic channel assignment method of the graduate TD SDMA group system integrated service characteristic of a kind of synthetic user business and transmission conditions.

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

At first, here the term definition of definition is as follows:

DCA: dynamic channel allocation

T _Ap: re-start the time of slow DCA, can adjust by the frequency that changes the business of up/down industry

L a: 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 a frame

Ch _{I, j}: in group, user i is at time slot t _jThe physical channel of upper correspondence

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 upper 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 upper signal transmission

T _Tari: the target call of data service user i to 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 that re-starts slow DCA

N _Tu: the uplink service timeslot number

N _Td: the downlink business timeslot number

Min (): getting the expression formula made in bracket in variables collection is 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 upper and lower provisional capital needs allocation of channel resources; The remote measuring and controlling formula need to 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, i.e. 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, resource is distributed to group, for the uplink resource allocation of group; Fast DCA is business characteristic according to the TD-SCDMA cluster user, channel transfer characteristic, user's quality of service requirement, by dividing speech, data, reserved time slot and definition variable boundary, physical channel is distributed to bearer service, for the uplink resource allocation of group user.

Described slow DCA: for adapting to the variation of cluster communication service rate, at first system carries out slow DCA, every T _ApTime is adjusted the number of timeslots in Uplink/Downlink; Obtain service parameter, according to service parameter, judge which kind of in A interactive mode, B remote measuring and controlling formula, 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, in uplink communication, only has the user of call request to initiate request, need allocation of channel resources, 6 business time-slots are only arranged in the TD-SCDMA system, therefore, 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 that re-starts slow DCA, therefore have

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

Finally, according to minimizing

Principle find most suitable 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 formula, γ is up-downgoing data service rate, N _TuFor uplink service timeslot number, N _TdFor the downlink business timeslot number, function min () is at (N _Tu: N _Td) get in set and make expression formula

(N for minimum _Tu: N _Td) value;

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

In the application of C broadcast type, control desk only is sent to message the geographic area of restriction, needn't confirm, message is retransmitted several times within a period of time, and to increase the reliability received, 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 service parameter according to a preliminary estimate, carry out the application type judgement, determine which kind of application is current group system be in, when a certain class is applied, slow DCA being cut to corresponding flow process when decision-making system, is the category-A application if judge, enter the slow DCA flow process of category-A, if judge it is the category-B application, enter the slow DCA flow process of category-B, if judge it is the application of C class, 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 for category-A and category-B application is designed, adopt the variable boundary strategy to realize the dynamic assignment 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 a frame is divided according to speech, data and reserved type of service, first variable boundary is used for defining voice and reserved business, second variable boundary is used for defining 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 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 in group that voice service user i is at j time slot t _j, j=1,2 ..., the upper 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 upper 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 transmitted on physical channel is

Corresponding channel capacity is C _i, and

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

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, for adjusting coefficient, are the empirical values according to data are carried out matching in the past;

Data user's priority criteria: be both the user of data service according to uplink physical channel transmission conditions, user's qos parameter, time of delay determining its priority factor, time slot is at war with, tentation data service-user i is at time slot t _j, j=1,2 ..., the upper 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 upper transmission is

At channel ch _{I, j}The time delay of upper signal transmission is

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

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

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

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

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

Wherein, a, b and c, for adjusting coefficient, are the empirical values according to data are carried out matching in the past;

Reserved time slot priority criteria: the priority of voice service is all the time higher than data service, and when having voice service to seize reserved time slot, the priority height overall is in data service.When not having speech business to seize reserved time slot, reserved time slot is used in data service.

Described fast DCA, its flow process is: at first base station obtains the service parameter of up user's request channel resource, according to parameter judgement uplink service, is speech or data; If voice service, at first check that 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, enter the time slot competition of reserved time slot, according to reserved time slot priority criteria program calculating priority level, and carry out time slot allocation by the priority factor calculated, whether the reserved time slot of judgement takes, if reserved time slot is full, apply for that the user enters service queue, this time slot allocation finishes; If reserved time slot less than, apply for that the user accepts to distribute indication; If the judgement user is data service, check that whether data slot is full, if data slot does not take, enter data service priority criterion 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, enter the time slot competition of reserved time slot, according to reserved time slot priority criteria program calculating priority level, and carry out time slot allocation by the priority factor calculated, whether the reserved time slot of judgement takes, if reserved time slot is full, apply for that the user enters service queue, this time slot allocation finishes; If reserved time slot less than, apply for that the user accepts to distribute indication.

Beneficial effect: the invention provides a kind of TD-SCDMA group system graduation dynamic channel allocation algorithm that carries out the resource size distribution in the Digital Clustering mobile communication system 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 Trunking Technologies progress, promote the competitiveness of China's Mobile Communication Industry in international market, and help every profession and trade to enhance productivity, accelerate development and the industrial upgrading of national economy.

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

The accompanying drawing explanation

By below in conjunction with accompanying drawing 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 the slow DCA time slot allocation diagram that three class application are carried out for group system.

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 diagram carried out for 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 application 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 restriction, needn't confirm.Message can be retransmitted several times within a period of time, to increase the reliability received.The transaction application is comprised of two message usually, and one is solicit operation, and another is to confirm that whether this operation is successful, and two message complete the primary information exchange.Some affairs may comprise repeatedly information exchange, as Card Verification, paging, voice mailbox notice, email notification and Email are delivered.Interactive application need to and provide between the dispatching desk computer of business at travelling carriage carries out repeatedly message, comprises terminal access host, database access and remote lan access.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 large 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 upper and lower provisional capital needs allocation of channel resources; The remote measuring and controlling formula need to 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, i.e. slow DCA and fast DCA.Slow DCA distributes to group by resource, for the uplink resource allocation of group; Fast DCA distributes to bearer service by physical channel, for the uplink resource allocation of group user.Below will illustrate 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, at first system carries out slow DCA, every T _ApTime is adjusted the number of timeslots in Uplink/Downlink.At first, obtain service parameter, according to service parameter, judge which kind of in A interactive mode, B remote measuring and controlling formula, C broadcast type be the type of service of group system be;

In the category-A application, the downlink broadcast channel is shared by all groups, in uplink communication, only has the user of call request to initiate request, needs allocation of channel resources.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:

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

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,

$\mathrm{\&gamma;}={\stackrel{\&OverBar;}{L}}_u/L_d$

Finally, according to minimizing

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

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

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

In the application of C class, control desk only is sent to message the geographic area of restriction, needn't confirm.Message can be retransmitted several times within a period of time, to increase the reliability received.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 is only designed for the up channel distribution of category-A and category-B application.Adopt the variable boundary strategy to realize the dynamic assignment 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 a frame is divided according to speech, data and reserved type of service.First variable boundary is used for defining voice and reserved business, and second variable boundary is used for defining 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 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 in group that voice service user i is at time slot t _j, j=1,2 ..., the upper 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 upper 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 transmitted on physical channel is

Corresponding channel capacity is C _i, and

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

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, for adjusting coefficient, are the empirical values according to data are carried out matching in the past.

2) data user's priority criteria

Be both the user of data service according to uplink physical channel transmission conditions, user's qos parameter, time of delay determining its priority factor, time slot is at war with, tentation data service-user i is at time slot t _j, j=1,2 ..., the upper 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 upper transmission is

At channel ch _{I, j}The time delay of upper signal transmission is

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

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

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

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

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

Wherein, a, b and c, for adjusting coefficient, are the empirical values according to data are carried out matching in the past.

3) reserved time slot priority criteria

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

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

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 the slow DCA time slot allocation diagram that three class application are carried out for group system.

With reference to Fig. 1, show in a 5ms subframe time slot allocation situation for 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 the category-A application (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

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

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,

$\mathrm{\&gamma;}={\stackrel{\&OverBar;}{L}}_u/L_d$

Finally, according to minimizing

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

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

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

For the application of C class (step 106), control desk only is sent to message the geographic area of restriction, needn't confirm.Message can be retransmitted several times within a period of time, to increase the reliability received.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), according to service parameter according to a preliminary estimate, carry out application type judgement (step 212), determine current group system is in which kind of application (step 214).When decision-making system during in the application of a certain class, slow DCA is cut to corresponding flow process, if judge it is the category-A application, enter the slow DCA flow process of category-A (step 216), if judge, be the category-B application, enter the slow DCA flow process of category-B (step 216), if judge it is the application of C class, 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 the fast DCA time slot allocation diagram that three class application are carried out for group system.

With reference to Fig. 3, in a frame length that comprises L time slot, time slot is divided to three class time slot sections by Moving Boundary A and Moving Boundary B: segment of speech (302), data segment (304) and reserved section (306).Variable boundary A is used for defining voice and reserved business, and variable boundary B is used for defining reserved 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 group.Define respectively different User Priority criterions 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 in group that voice service user i is at time slot t _j, j=1,2 ..., the upper 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 upper 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 transmitted on physical channel is

Corresponding channel capacity is C _i, and

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

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, for adjusting coefficient, are the empirical values according to data are carried out matching in the past.

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

Be both the user of data service according to uplink physical channel transmission conditions, user's qos parameter, time of delay determining its priority factor, time slot is at war with, tentation data service-user i is at time slot t _j, j=1,2 ..., the upper 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 upper transmission is

At channel ch _{I, j}The time delay of upper signal transmission is

The target packet loss of data service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio transmitted on physical channel is Corresponding channel capacity is C _i, the time delay of data service user i requires as T _Tari, and

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

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

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

Wherein, a, b and c, for adjusting coefficient, are the empirical values according to data are carried out matching in the past.

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

The priority of voice service is all the time higher than data service, and when having voice service to seize reserved time slot, the priority height overall is in data service.When not having speech business to seize reserved time slot, data service can be used reserved 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 base station obtains the service parameter (step 410) of up user's request channel resource, according to parameter judgement 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, enter the time slot competition of reserved time slot, according to reserved time slot priority criteria program calculating priority level (step 420), and carry out time slot allocation (step 422) by the priority factor calculated, whether the reserved time slot of judgement has taken (step 424), if reserved time slot is full, apply for that the user enters service queue, this time slot allocation finishes (step 426).If reserved time slot less than, apply for that the user accepts to distribute indication (step 434).If be data service step 412 judgement user, check data slot whether full (step 428), if data slot does not take, enter data service priority criterion 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, enter the time slot competition of reserved time slot, according to reserved time slot priority criteria program calculating priority level (step 420), and carry out time slot allocation (step 422) by the priority factor calculated, whether the reserved time slot of judgement has taken (step 424), if reserved time slot is full, apply for that the user enters service queue, this time slot allocation finishes (step 426).If reserved time slot less than, apply for that the user accepts to distribute indication (step 434).

Claims (3)

1. the dynamic channel assignment method of a CDMA cluster system integrated service and transmission 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 upper and lower provisional capital needs allocation of channel resources; The remote measuring and controlling formula need to 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, i.e. 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, resource is distributed to group, for the uplink resource allocation of group; Fast DCA is business characteristic according to the TD-SCDMA cluster user, channel transfer characteristic, user's quality of service requirement, by dividing speech, data, reserved time slot and definition variable boundary, physical channel is distributed to bearer service, for the uplink resource allocation of group user;

Described slow DCA: for adapting to the variation of cluster communication service rate, at first system carries out slow DCA, every T _ApTime is adjusted the number of timeslots in Uplink/Downlink; Obtain service parameter, according to service parameter, judge which kind of in A interactive mode, B remote measuring and controlling formula, 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, in uplink communication, only has the user of call request to initiate request, need allocation of channel resources, 6 business time-slots are only arranged in the TD-SCDMA system, therefore, up-downgoing traffic assignments rate choosing value is 2:4,3:3,4:2; Consider the characteristics of group system, descending link load L _dBe known, the uplink load of each group is estimated by following formula:

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 that re-starts slow DCA, therefore have

Finally, according to minimizing

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

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

(N for minimum _Tu: N _Td) value;

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

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

Described fast DCA: in fast DCA, only the up channel distribution for category-A and category-B application is designed, adopt the variable boundary strategy to realize the dynamic assignment 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 a frame is divided according to speech, data and reserved type of service, first variable boundary is used for defining voice and reserved business, second variable boundary is used for defining 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 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 in group that voice service user i is at j time slot t _j, j=1,2 ..., the upper corresponding physical channel of L is ch _i,j, the transmission rate of voice service user i is R _voi, at ch _i,jOn channel capacity be C _i,j, at channel ch _i,jThe signaling channel noise ratio of upper 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 transmitted on physical channel is

Corresponding channel capacity is C _i, and

Definition priority factor f _i,jAs follows:

Wherein, α and β, for adjusting coefficient, are the empirical values according to data are carried out matching in the past; Ch _i,jIn sign group, user i is at time slot t _jThe physical channel of upper correspondence,

Mean that service-user i is at channel ch _i,jThe signaling channel noise ratio of upper transmission,

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

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

At channel ch _i,jThe time delay of upper signal transmission is The target packet loss of data service user i or bit error probability are P _Ei, the corresponding echo signal interchannel noise ratio transmitted on physical channel is

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

Definition priority factor f _i,jAs follows:

Wherein, a, b and c, for adjusting coefficient, are the empirical values according to data are carried out matching in the past;

Reserved time slot priority criteria: the priority of voice service is all the time higher than data service, and when having voice service to seize reserved time slot, the priority height overall is in data service, and when not having speech business to seize reserved time slot, reserved time slot is used in data service.

2. the dynamic channel assignment method of CDMA cluster system integrated service according to claim 1 and transmission characteristic, 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 service parameter according to a preliminary estimate, carry out the application type judgement, determine which kind of application is current group system be in, when a certain class is applied, slow DCA being cut to corresponding flow process when decision-making system, is the category-A application if judge, enter the slow DCA flow process of category-A, if judge it is the category-B application, enter the slow DCA flow process of category-B, if judge it is the application of C class, enter the slow DCA flow process of C class, when having assigned, finish slow DCA, and wait for next T _ApTime.

3. the dynamic channel assignment method of CDMA cluster system integrated service according to claim 1 and transmission characteristic, it is characterized in that described fast DCA, its flow process is: at first base station obtains the service parameter of up user's request channel resource, according to parameter judgement uplink service, is speech or data; If voice service, at first check that 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, enter the time slot competition of reserved time slot, according to reserved time slot priority criteria program calculating priority level, and carry out time slot allocation by the priority factor calculated, whether the reserved time slot of judgement takes, if reserved time slot is full, apply for that the user enters service queue, this time slot allocation finishes; If reserved time slot less than, apply for that the user accepts to distribute indication; If the judgement user is data service, check that whether data slot is full, if data slot does not take, enter data service priority criterion 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 data slot according to priority; If data slot takes, enter the time slot competition of reserved time slot, according to reserved time slot priority criteria program calculating priority level, and carry out time slot allocation by the priority factor calculated, whether the reserved time slot of judgement takes, if reserved time slot is full, apply for that the user enters service queue, this time slot allocation finishes; If reserved time slot less than, apply for that the user accepts to distribute indication.

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