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

Abstract

The dynamic channel allocation method of code division multiple access trunking system with comprehensive service and transmission characteristics relates to a TD-SCDMA trunking system classification in which resources are allocated according to channel status, service type, user priority and other factors in a digital trunking mobile communication system The method of dynamic channel allocation, first, classifies the business of the TD-SCDMA trunking system, and defines the business types of the TD-SCDMA trunking system as: A interactive, B telemetry and remote control; secondly, the involved TD-SCDMA trunking system DCA includes Two basic processes, namely slow DCA and fast DCA; slow DCA is based on the application type of the TD-SCDMA trunking system, by defining switching points of different application business types, resources are allocated to the group for the uplink of the group Resource allocation; fast DCA allocates physical channels to bearer services by dividing data, reserving time slots, and defining variable boundaries according to the service characteristics of TD-SCDMA cluster users, channel transmission characteristics, and user quality of service requirements. Uplink resource allocation for group users.

Description

A Dynamic Channel Allocation Method for Combined Service and Transmission Characteristics of Code Division Multiple Access Trunking System

technical field

Trunking communication uses PTT signaling to preempt the call right, and at the same time, the base station allocates uplink shared channels and downlink shared channels for this call, and dynamic allocation of resources can obtain efficient resource occupation under limited system resources. The present invention generally relates to a TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) code division multiple access (TD-SCDMA) technology that allocates resources according to factors such as channel status, service type, and user priority in a digital trunking mobile communication system. ) Classified dynamic channel allocation algorithm for trunking systems.

Background technique

In the "Digital Trunking Mobile Communication System System", my country has determined that the frequency band used by digital trunking mobile communication is 800MHz. The uplink and downlink are 806MHz-821MHz and 851MHz-866MHz respectively, a total of 15MHz, the duplex interval is 45MHz, and the channel interval is 25kHz. Since April 2003, our country has carried out commercial trials of common network digital trunking services in some domestic cities. Among them, the former China Satcom opened the iDEN operation common network in Shanghai; Beijing Zhengtong Company built the TETRA mobile government affairs common network in Beijing. Almost all urban light rail traffic communications in the country have adopted the TETRA system. my country's self-developed digital trunking communication system GoTa has built multiple networks in China, and the original China Railcom has also built and opened a GT800 system commercial test network in Chongqing. The development status of my country's digital trunking communication is still in the initial stage compared with foreign developed regions, and the digital trunking system with national independent intellectual property rights has just begun to develop, no matter from the perspective of digital trunking communication market development or national industry development. This present situation is both a challenge and an opportunity for the development of our country's future digital trunking communication system. The TD-SCDMA system based on TDD technology not only has all the technical capabilities of 3G when developing PTT (push-to-talk) services, but also has a unique advantage that other 3Gs do not have: the asymmetric uplink and downlink of TD-SCDMA The time slot allocation capability can allocate uplink and downlink resources according to the business volume, which is very useful for the trunking system of half-duplex communication. At the same time, TD-SCDMA wireless access technology, which is an international standard of 3GPP, expands to a digital trunking system with independent intellectual property rights on this basis, which can further expand the application space and industrial competitiveness of TD-SCDMA technology, and is also fully in line with the requirements of trunking systems. Technology development direction and national interest development strategy.

The calls in the mobile communication system are all point-to-point communication methods. The system only needs to establish a pair of signaling connections and service channels to meet the calling needs of the caller and the called party. The service channels provided by the system are all users in the call. dedicated. Most of the calls in the trunking communication system are point-to-multipoint, and the service information is shared. At this time, there is one calling user and many called users. Everyone monitors a service channel, and the called user Probably not distributed in one area. This requires the system to establish signaling connections and shared service channels for each area, and at the same time change the service area provided in real time according to the movement of group users, and establish signaling connections and shared services in new areas where group users arrive. channel. The shared channel method of the trunking communication system is much more complicated than the dedicated channel method of mobile communication, and there are many management contents of wireless resources involved in the modification, and many resource allocation algorithms and parameter calibration need to be reconsidered. The improvement of this algorithm and the calibration of parameters are also a process of continuous optimization and a relatively time-consuming process.

A Dynamic Channel Allocation Method for Integrated Service Characteristics of Time Division Synchronous Code Division Multiple Access Trunking System

Contents of the invention

Technical problem: The purpose of the present invention is to support trunking services on the basis of the existing TD physical layer frame structure. The technical difficulties include: since the uplink traffic channel and the downlink traffic channel of the trunking are shared, in the uplink, multiple users are divided into Time-preemptive sharing, in the downlink, multiple users (except the caller) share at the same time. This channel mapping method is completely different from the channel mapping method of common mobile communication, and it is easy to introduce instability. Furthermore, since trunking communication is a half-duplex one-way channel, for the listener (called), a closed-loop communication link cannot be formed, and effective power control cannot be performed, so that the system cannot confirm the correct transmission power of the signal. Strike a balance between capacity and coverage.

Based on the analysis of the above existing problems, the present invention allocates resource sizes by comprehensively considering factors such as channel status, service type, and user priority of group users in different groups, and designs a grading that integrates user services and transmission conditions A method for dynamic channel allocation based on integrated service characteristics of time division synchronous code division multiple access trunking system.

Technical solution: The present invention provides a TD-SCDMA trunking system hierarchical dynamic channel allocation algorithm for resource size allocation in a digital trunking mobile communication system based on factors such as channel status, service type, and user priority.

First, the terms defined here are defined as follows:

DCA: Dynamic Channel Allocation

T _ap : The time to perform slow DCA again, which can be adjusted by changing the frequency of uplink/downlink services

L: number of slots in a frame

L _d : Downlink link load

L _u : Uplink link load

f(·): A predictive function for business traffic designed according to the number of users in a single group and business type

：上行链路负载均值

: Uplink load average

nT _ap : current moment of group DCA

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

γ: uplink and downlink data service rate

t _j : the jth time slot in a frame

ch _{i, j} : the physical channel corresponding to user i in the group on time slot t _j

R _voi : transmission rate of voice service user i

C _{i, j} : channel capacity of business user i on ch _{i, j}

：业务用户i在信道ch_i，j上传输的信号信道噪声比

: The channel-to-noise ratio of the signal transmitted by service user i on channel ch _i,j

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

：业务用户i在物理信道上传输的目标信号信道噪声比

: The target signal-to-channel-to-noise ratio of service user i transmitted on the physical channel

C _i : the target channel capacity of service user i transmitted on the physical channel

：数据用户i在信道ch_i，j上传输信号的时间延迟

: time delay of data user i transmitting signal on channel ch _i,j

T _tari : the target requirement of data service user i for time delay

α: adjustment factor for business user computing priority

β: Adjustment factor for business user computing priority

a: adjustment factor for data user computing priority

b: Adjustment factor for data user computing priority

c: Adjustment factor for data user computing priority

n: the nth _Tap time, that is, the time when the nth slow DCA is re-performed

N _tu : Number of uplink business time slots

N _td : Number of downlink service time slots

min(): Take the variable value that makes the expression in parentheses the smallest in the variable set

First, classify the business of TD-SCDMA trunking system, and define the business types of TD-SCDMA trunking system as: A interactive, including digital scheduling, data query and transaction processing applications; B telemetry and remote control; C broadcast three types; Interactive uplink and downlink need to allocate channel resources; telemetry and remote control need to allocate uplink channel resources; broadcast need to allocate downlink resources;

Secondly, the involved TD-SCDMA trunking system dynamic channel allocation DCA includes two basic processes, namely slow DCA and fast DCA; slow DCA is based on the application type of the TD-SCDMA trunking system, by defining the switching point of different application business types, Allocate resources to groups for uplink resource allocation of groups; fast DCA divides voice, data, and reserved time according to the service characteristics of TD-SCDMA cluster users, channel transmission Slots and variable boundaries are defined to allocate physical channels to bearer services for uplink resource allocation of group users.

Described slow DCA: In order to adapt to the change of trunking communication service rate, the system first performs slow DCA, every T _ap time to adjust the number of time slots in the up/down link; obtain business parameters, judge the trunking system according to the business parameters Which type of service is A interactive, B telemetry and remote control, and C broadcast;

In A interactive application, all groups share the downlink broadcast channel. In uplink communication, only users with call requests initiate requests and need to allocate channel resources. In the TD-SCDMA system, there are only 6 business time slots. Therefore, the uplink and downlink The selected value of the service distribution ratio is 2:4, 3:3, 4:2; considering the characteristics of the cluster system, the downlink load L _d is known, and the uplink load of each group is given by the following formula sub to estimate:

${\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; n</span>}}_{\mathrm{<span\; class="notranslate">\; ap</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; ap</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>$

可以计算得到上下行数据业务率γ，n是Tap时间的个数，即第n个重新进行慢DCA的时间，因此有Among them, the function f( ) is a predictive function for traffic flow designed according to the number of users and business types of a single group, that is, the uplink load of the group nT _ap at the current moment is based on the previous moment (n-1) The estimated mean value obtained by _Tap and the empirical mean value of historical records, according to the estimated current moment

The uplink and downlink data service rate γ can be calculated, and n is the number of Tap times, that is, the nth time to re-do slow DCA, so there is

$\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; =</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}$

的原则找到最合适的上下行时隙分配方案，表示为下面的式子：Finally, according to the minimized

The principle of finding the most suitable uplink and downlink time slot allocation scheme is expressed as the following formula:

$<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}<span\; class="notranslate">\; :</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span><span\; class="notranslate">\; \{</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \}</span>}{\mathrm{<span\; class="notranslate">\; min</span>}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; |</span>\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; )</span>$

为最小的(N_tu∶N_td)值；In the formula, γ is the uplink and downlink data traffic rate, N _tu is the number of uplink business time slots, N _td is the number of downlink business time slots, and the function min() is the expression that is obtained in the (N _tu : N _td ) set

is the smallest (N _tu : N _td ) value;

In B telemetry and remote control applications, the console only needs to collect and monitor the transmission data from group users. Therefore, in slow DCA, the uplink and downlink service allocation ratio is selected as 4:2;

In the C broadcast application, the console only transmits the message to a limited geographical area without confirmation, and the message is resent several times within a period of time to increase the reliability of reception. Therefore, in slow DCA, the uplink and downlink business distribution The selected ratio is 2:4.

The process of the slow DCA is as follows: when the time variable t<T _ap , perform the slow DCA process, first obtain the business parameters, and judge the application type according to the preliminary estimation of the business parameters to determine which cluster system is currently in. In class applications, when it is judged that the system is in a certain class of applications, the slow DCA will be cut into the corresponding process. If it is judged to be a class A application, it will enter the class A slow DCA process. If it is judged to be a class B application, it will enter the class B slow DCA process. If it is determined that it is a Class C application, enter the Class C slow DCA process. When the allocation is completed, end the slow DCA and wait for the next _Tap time.

The fast DCA: In the fast DCA, only the uplink channel allocation of Class A and Class B applications is designed, and the variable boundary strategy is used to realize the dynamic allocation of channel resources. By defining two variable boundaries, three different Assign the uplink channel according to the priority criterion;

Two variable boundaries: divide time slots in a frame according to voice, data and reserved service types, the first variable boundary is used to define voice and reserved services, and the second variable boundary is used to define reserved services Retention and data services, the definition of the two boundaries is also determined based on the experience value estimation of previous user services in the group;

Three different priority criteria, including voice user priority criteria:

相应的信道容量为C_i，并且Users who are also in the voice service determine their priority coefficients according to the uplink physical channel transmission conditions and user QoS parameters, and compete for the time slots. Assume that the voice service user i in the group is in the jth time slot t _j , j=1, 2, ..., the corresponding physical channel on L is ch _{i, j} , the transmission rate of voice service user i is R _voi , the channel capacity on ch _{i, j} is C _{i, j} , and the transmission on channel ch _{i, j} The signal-to-channel-to-noise ratio of The target packet loss rate or bit error probability of voice service user i is P _Ei , and the corresponding channel-to-noise ratio of the target signal transmitted on the physical channel is

The corresponding channel capacity is C _i , and

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; voi</span>}}\mathrm{<span\; class="notranslate">\; log</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; ch</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span>$

Define the priority coefficient f _{i, j} as follows:

f _i,j =α|C _i,j -C _i |+β|γ _i,j -γ _i |

Among them, α and β are adjustment coefficients, which are empirical values fitted according to previous data;

在信道ch_i，j上传输信号的时间延迟为

数据业务用户i的目标丢包率或者误比特概率为P_Ei，对应的在物理信道上传输的目标信号信道噪声比为

相应的信道容量为C_i，数据业务用户i的时间延迟要求为T_tari，并且Data user priority criterion: Users of the same data service determine their priority coefficients according to uplink physical channel transmission conditions, user QoS parameters, and delay time, and compete for time slots. Assume that data service user i is in time slot t _j , j =1, 2, ..., the corresponding physical channel on L is ch _{i, j} , the transmission rate of data service user i is R _dati , the channel capacity on ch _{i, j} is C _{i, j} , and on channel ch _i, The channel-to-noise ratio of the signal transmitted on _j is

The time delay of transmitting a signal on channel ch _{i, j} is

The target packet loss rate or bit error probability of data service user i is P _Ei , and the corresponding target signal-to-channel-to-noise ratio transmitted on the physical channel is

The corresponding channel capacity is C _i , the time delay requirement of data service user i is T _tari , and

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; dati</span>}}\mathrm{<span\; class="notranslate">\; log</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; ch</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span>$

Define the priority coefficient f _{i, j} as follows:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; b</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{{\mathrm{<span\; class="notranslate">\; tar</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; tari</span>}}<span\; class="notranslate">\; |</span>$

Among them, a, b and c are adjustment coefficients, which are empirical values fitted according to previous data;

Priority criteria for reserved time slots: the priority of voice services is always higher than that of data services. When a voice service preempts a reserved time slot, the priority is always higher than that of data services. When no voice service occupies the reserved time slot, the data service uses the reserved time slot.

Described fast DCA, its flow process is: at first base station obtains the business parameter that uplink user applies for channel resource, judges uplink business according to parameter whether voice or data; If it is voice business, first check whether voice time slot is full, if voice time slot If it is not fully occupied, enter the voice service priority criterion program to calculate the allocation priority of the current application user, compare the calculated priority with the priority of other voice service users requesting resources at the same time, and perform voice time slot allocation according to the priority Allocation; if the voice time slot is full, enter the time slot competition of the reserved time slot, calculate the priority according to the reserved time slot priority criterion program, and carry out time slot allocation according to the calculated priority coefficient, and judge the reserved time slot Whether the time slot is full, if the reserved time slot is full, the applicant user enters the service queue, and the time slot allocation ends this time; if the reserved time slot is not full, the applicant user accepts the allocation instruction; if it is judged that the user is a data service , then check whether the data time slot is full, if the data time slot is not full, enter the data service priority criterion program to calculate the allocation priority of the current applicant user, and compare the calculated priority with other data services requesting resources at the same time Compare user priorities, and allocate voice time slots according to the priority; if the voice time slot is full, enter the time slot competition of the reserved time slot, calculate the priority according to the reserved time slot priority criterion program, and press The calculated priority coefficient is used to allocate time slots to determine whether the reserved time slots are full. If the reserved time slots are full, the applicant user enters the service queue, and this time slot allocation ends; if the reserved time slots are not full , the requesting user accepts the allocation instruction.

Beneficial effects: the present invention provides a TD-SCDMA trunking system hierarchical dynamic channel allocation algorithm for resource size allocation in the digital trunking mobile communication system according to factors such as channel state, service type, and user priority.

The achievement of this invention belongs to independent innovation, self-owned brand, independent intellectual property rights, and has international advanced level. It will fill the domestic gap, break the international monopoly, promote the progress of domestic digital cluster technology, enhance the competitiveness of my country's mobile communication industry in the international market, help various industries improve production efficiency, and accelerate the development of the national economy and industrial upgrading.

The invention enables the TD-SCDMA system to support the requirement of cluster communication on the original basis, realizes resource sharing among various services, improves resource utilization rate, and obtains higher frequency band utilization rate.

Description of drawings

The above and other objects, features and advantages of the present invention will become more clear through the following detailed description in conjunction with the accompanying drawings, wherein;

Fig. 1 shows a diagram of slow DCA time slot allocation for three types of applications in a trunking system.

Fig. 2 shows an operation flowchart of the trunking system performing slow DCA time slot allocation.

Fig. 3 shows a diagram of fast DCA time slot allocation for two types of services in the trunking system.

Fig. 4 shows an operation flow chart of the trunking system performing fast DCA time slot allocation.

Detailed ways

1. TD-SCDMA trunking system business type:

The application of cluster system business can be classified into three categories: broadcast application, transaction processing application and interactive application. Broadcast applications include general messaging, announcements and advertisements. In broadcast applications, messages are only delivered to a limited geographic area without acknowledgment. Messages can be resent several times over a period of time to increase reliability of reception. A transaction processing application usually consists of two messages, one is to request an operation, and the other is to confirm whether the operation is successful, and the two messages complete an information exchange. Some transactions may involve multiple exchanges of information, such as credit card authentication, paging, voicemail notification, email notification, and email delivery. Interactive applications require multiple message exchanges between the mobile station and the dispatcher computer that provides services, including terminal access to the host, database access, and remote LAN access. Mobile data services can be applied to public security, administrative management, transportation and many industrial fields. The basic types of mobile data users can be divided into five categories: digital dispatching, data query, telemetry and remote control, browsing and publishing.

According to the above classification, in the present invention, the TD-SCDMA trunking system service types are defined as: interactive, including digital scheduling, data query and transaction processing applications; telemetry and remote control; broadcasting three types. Both interactive uplink and downlink need to allocate channel resources; telemetry and remote control need to allocate uplink channel resources; broadcast need to allocate downlink resources.

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

The DCA of the TD-SCDMA trunking system involved in the present invention includes two basic processes, that is, slow DCA and fast DCA. Slow DCA allocates resources to groups for group uplink resource allocation; fast DCA allocates physical channels to bearer services for group user uplink resource allocation. The algorithms and processes of the slow DCA and the fast DCA will be described in detail below.

2.1 Slow DCA

In order to adapt to the change of the traffic rate of the trunking communication, the system first performs slow DCA, and adjusts the number of time slots in the uplink/downlink every T _ap time. First, obtain business parameters, and judge which type of business of the trunking system is A interactive, B telemetry and remote control, and C broadcast according to the business parameters;

In Type A applications, all groups share the downlink broadcast channel, and in uplink communication, only users with call requests initiate requests and need to allocate channel resources. There are only 6 service time slots in the TD-SCDMA system, therefore, the optional values of the uplink and downlink service allocation ratios are 2:4, 3:3, 4:2. Considering the characteristics of the trunking system, the downlink load L _d is known, and the uplink load of each group can be estimated by the following formula:

${\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; n</span>}}_{\mathrm{<span\; class="notranslate">\; ap</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; ap</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>$

可以计算得到上下行数据业务率γ，即Among them, the function f( ) is a predictive function for traffic flow designed according to the number of users and business types of a single group, that is, the uplink load of the group nT _ap at the current moment is based on the previous moment (n-1) Estimated mean from _Tap and historical empirical mean. according to the estimated current

The uplink and downlink data service rate γ can be calculated, namely

$\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; =</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}$

的原则找到最合适的上下行时隙分配方案，表示为下面的式子：Finally, according to the minimized

The principle of finding the most suitable uplink and downlink time slot allocation scheme is expressed as the following formula:

$<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}<span\; class="notranslate">\; :</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span><span\; class="notranslate">\; \{</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \}</span>}{\mathrm{<span\; class="notranslate">\; min</span>}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; |</span>\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; )</span>$

In Type B applications, the console only needs to collect and monitor the transmission data from group users. Therefore, in slow DCA, the optional value of uplink and downlink service allocation ratio is 4:2.

In Class C applications, the console only transmits messages to a limited geographic area without confirmation. Messages can be resent several times over a period of time to increase reliability of reception. Therefore, in slow DCA, the optional value of the allocation ratio of uplink and downlink services is 2:4.

2.2 Fast DCA

In fast DCA, the present invention is only designed for the uplink channel allocation of Class A and Class B applications. The variable boundary strategy is used to realize the dynamic allocation of channel resources. By defining two variable boundaries, three different priority criteria allocate uplink channels.

Two variable boundaries: divide the time slots in a frame according to voice, data and reserved service types. The first variable boundary is used to define voice and reservation services, and the second variable boundary is used to define reservation and data services. The definitions of the two boundaries are also determined based on the estimation of the empirical value of the previous user services in the group.

Three different priority criteria:

1) Voice user priority criteria

话音业务用i的目标丢包率或者误比特概率为P_Ei，对应的在物理信道上传输的目标信号信道噪声比为相应的信道容量为C_i，并且Users who are also in the voice service determine their priority coefficients according to the transmission conditions of the uplink physical channel and user QoS parameters, and compete for the time slots. Assume that the voice service user i in the group is in the time slot t _j , j=1, 2,... , the corresponding physical channel on L is ch _{i, j} , the transmission rate of voice service user i is R _voi , the channel capacity on ch _{i, j} is C _{i, j} , and the signal channel transmitted on channel ch _{i, j} Noise ratio is

The target packet loss rate or bit error probability for voice service i is P _Ei , and the corresponding channel-to-noise ratio of the target signal transmitted on the physical channel is The corresponding channel capacity is C _i , and

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; voi</span>}}\mathrm{<span\; class="notranslate">\; log</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; ch</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span>$

Define the priority coefficient f _{i, j} as follows:

f _i,j =α|C _i,j -C _i |+β|γ _i,j -γ _i |

Among them, α and β are adjustment coefficients, which are empirical values fitted according to previous data.

2) Data User Priority Criteria

在信道ch_i，j上传输信号的时间延迟为

数据业务用户i的目标丢包率或者误比特概率为P_Ei，对应的在物理信道上传输的目标信号信道噪声比为

相应的信道容量为C_i，数据业务用户i的时间延迟要求为T_tari，并且Users of the same data service determine their priority coefficients according to the transmission conditions of the uplink physical channel, user QoS parameters, and delay time, and compete for time slots. Assume that data service user i is in time slot t _j , j=1, 2,... , the corresponding physical channel on L is ch _{i, j} , the transmission rate of data service user i is R _dati , the channel capacity on ch _{i, j} is C _{i, j} , and the signal channel transmitted on channel ch _{i, j} Noise ratio is

The time delay of transmitting a signal on channel ch _{i, j} is

The target packet loss rate or bit error probability of data service user i is P _Ei , and the corresponding target signal-to-channel-to-noise ratio transmitted on the physical channel is

The corresponding channel capacity is C _i , the time delay requirement of data service user i is T _tari , and

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; dati</span>}}\mathrm{<span\; class="notranslate">\; log</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; ch</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span>$

Define the priority coefficient f _{i, j} as follows:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; b</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{{\mathrm{<span\; class="notranslate">\; tar</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; tari</span>}}<span\; class="notranslate">\; |</span>$

Among them, a, b and c are adjustment coefficients, which are empirical values fitted according to previous data.

3) Reserved time slot priority criteria

The priority of the voice service is always higher than that of the data service. When a voice service preempts the reserved time slot, the priority is always higher than that of the data service. When no voice service occupies the reserved time slot, the data service can use the reserved time slot.

Preferred embodiments of the present invention will be described herein below with reference to the accompanying drawings. In the following description, known functions and constructions are not described again since they would obscure the invention in unnecessary detail.

Before describing the present invention, the terms used herein are defined as follows:

Three types of application types: refer to three types of cluster applications: A, interactive, B, telemetry and remote control, and C, broadcast.

Business type: Refers to two types of business types: voice and data.

A. Slow DCA

Fig. 1 shows a diagram of slow DCA time slot allocation for three types of applications in a trunking system.

Referring to FIG. 1 , it shows the time slot allocation situation of slow DCA applied to different clusters in one 5ms subframe. In the allocation process, there are two switching points, switching point A and switching point B, switching point A... is fixed, and for Class A applications (step 102), switching point B performs dynamic switching according to the uplink and downlink traffic ratio Channel allocation, first calculate the average traffic load of the uplink at the current moment

${\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; n</span>}}_{\mathrm{<span\; class="notranslate">\; ap</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; ap</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>$

可以计算得到上下行数据业务率γ，即Among them, the function f( ) is a predictive function for traffic flow designed according to the number of users and business types of a single group, that is, the uplink load of the group nT _ap at the current moment is based on the previous moment (n-1) Estimated mean from _Tap and historical empirical mean. according to the estimated current

The uplink and downlink data service rate γ can be calculated, namely

$\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; =</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}$

的原则找到最合适的上下行时隙分配方案，表示为下面的式子：Finally, according to the minimized

The principle of finding the most suitable uplink and downlink time slot allocation scheme is expressed as the following formula:

$<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}<span\; class="notranslate">\; :</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span><span\; class="notranslate">\; \{</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; :</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \}</span>}{\mathrm{<span\; class="notranslate">\; min</span>}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; |</span>\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; tu</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; td</span>}}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; )</span>$

For Class B applications (step 104), the console only needs to collect and monitor the transmission data from group users. Therefore, in slow DCA, the optional value of uplink and downlink service allocation ratio is 4:2.

For Class C applications (step 106), the console only transmits the message to a limited geographic area without confirmation. Messages can be resent several times over a period of time to increase reliability of reception. Therefore, in slow DCA, the optional value of the allocation ratio of uplink and downlink services is 2:4.

Fig. 2 shows an operation flowchart of the trunking system performing slow DCA time slot allocation.

Referring to FIG. 2, when the time t<T _ap , the slow DCA process is performed. First obtain the business parameters (step 210), and judge the application type according to the preliminary estimation of the business parameters (step 212), and determine which type of application the current cluster system is in (step 214). When it is judged that the system is in a certain type of application, the slow DCA is cut into the corresponding process, if it is determined to be a Class A application, enter the Class A slow DCA process (step 216), if it is determined to be a Class B application, enter the Class B slow DCA process ( Step 216), if it is judged to be a Class C application, enter the Class C slow DCA process (step 216), when the allocation is completed, end the slow DCA (step 218), and wait for the next _Tap time.

B. Fast DCA

Fig. 3 shows a diagram of fast DCA time slot allocation for three types of applications in the trunking system.

With reference to Fig. 3, in a frame length that includes L time slots, the time slots are divided into three types of time slot segments by movable boundary A and movable boundary B: voice segment (302), data segment (304) and reserved paragraph (306). Variable boundary A is used to define voice and reserved services, and variable boundary B is used to define reserved and data services. The definitions of the two boundaries are determined based on empirical value estimates of the traffic volume of past users in the group. Different user priority criteria are defined in the three types of time slots.

1, the voice user priority criterion (308) definition process is:

话音业务用户i的目标丢包率或者误比特概率为P_Ei，对应的在物理信道上传输的目标信号信道噪声比为

相应的信道容量为C_i，并且Users who are also in the voice service determine their priority coefficients according to the transmission conditions of the uplink physical channel and user QoS parameters, and compete for the time slots. Assume that the voice service user i in the group is in the time slot t _j , j=1, 2,... , the corresponding physical channel on L is ch _{i, j} , the transmission rate of voice service user i is R _voi , the channel capacity on ch _{i, j} is C _{i, j} , and the signal channel transmitted on channel ch _{i, j} Noise ratio is

The target packet loss rate or bit error probability of voice service user i is P _Ei , and the corresponding channel-to-noise ratio of the target signal transmitted on the physical channel is

The corresponding channel capacity is C _i , and

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; voi</span>}}\mathrm{<span\; class="notranslate">\; log</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; ch</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span>$

Define the priority coefficient f _{i, j} as follows:

f _i,j =α|C _i,j -C _i |+β|γ _i,j -γ _i |

Among them, α and β are adjustment coefficients, which are empirical values fitted according to previous data.

2. The data user priority criterion (310) defines the process as:

在信道ch_i，j上传输信号的时间延迟为

数据业务用户i的目标丢包率或者误比特概率为P_Ei，对应的在物理信道上传输的目标信号信道噪声比为

相应的信道容量为C_i，数据业务用户i的时间延迟要求为T_tari，并且Users of the same data service determine their priority coefficients according to the transmission conditions of the uplink physical channel, user QoS parameters, and delay time, and compete for time slots. Assume that data service user i is in time slot t _j , j=1, 2,... , the corresponding physical channel on L is ch _{i, j} , the transmission rate of data service user i is R _dati , the channel capacity on ch _{i, j} is C _{i, j} , and the signal channel transmitted on channel ch _{i, j} Noise ratio is

The time delay of transmitting a signal on channel ch _{i, j} is

The target packet loss rate or bit error probability of data service user i is P _Ei , and the corresponding target signal-to-channel-to-noise ratio transmitted on the physical channel is

The corresponding channel capacity is C _i , the time delay requirement of data service user i is T _tari , and

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; dati</span>}}\mathrm{<span\; class="notranslate">\; log</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; ch</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span>$

Define the priority coefficient f _{i, j} as follows:

${\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; b</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{{\mathrm{<span\; class="notranslate">\; tar</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; tari</span>}}<span\; class="notranslate">\; |</span>$

Among them, a, b and c are adjustment coefficients, which are empirical values fitted according to previous data.

3. The process of defining the reserved segment user priority criterion (312) is:

The priority of the voice service is always higher than that of the data service. When a voice service preempts the reserved time slot, the priority is always higher than that of the data service. When no voice service occupies the reserved time slot, the data service can use the reserved time slot.

Fig. 4 shows an operation flow chart of the trunking system performing fast DCA time slot allocation.

Referring to FIG. 4 , firstly, the base station obtains service parameters of uplink users applying for channel resources (step 410 ), and judges whether the uplink service is voice or data according to the parameters (step 412 ). If voice service, first check whether the voice time slot is full (step 414), if the voice time slot is not full, enter the voice service priority criterion program to calculate the distribution priority of the current application user (step 416), and calculate the obtained The priority is compared with the priority of other voice service users requesting resources at the same moment, and voice time slots are allocated according to the priority (step 418). If the voice time slot is full, then enter the time slot competition of the reserved time slot, calculate the priority (step 420) according to the priority criterion program of the reserved time slot, and carry out time slot allocation (step 420) by the priority coefficient that calculates. 422), judging whether the reserved time slot is full (step 424), if the reserved time slot is full, then the applicant user enters the service queue, and this time slot allocation ends (step 426). If the reserved time slot is not full, the requesting user accepts the allocation instruction (step 434). If judging that the user is a data service in step 412, then check whether the data time slot is full (step 428), if the data time slot is not full, enter the data service priority criterion program to calculate the distribution priority of the current application user (step 430) , comparing the calculated priority with the priority of other data service users requesting resources at the same moment, and performing voice time slot allocation according to the priority (step 432). If the voice time slot is full, then enter the time slot competition of the reserved time slot, calculate the priority (step 420) according to the priority criterion program of the reserved time slot, and carry out time slot allocation (step 420) by the priority coefficient that calculates. 422), judging whether the reserved time slot is full (step 424), if the reserved time slot is full, then the applicant user enters the service queue, and this time slot allocation ends (step 426). If the reserved time slot is not full, the requesting user accepts the allocation instruction (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:

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

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, n is the number of Tap time, i.e. n time of carrying out slow DCA again, therefore have

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

At last, according to minimizing

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

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

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

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

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 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

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

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 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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