CN101286946A - Method of service flow access control and bandwidth allocation based on OFDM system - Google Patents

Abstract

The invention relates to a service flow access control and bandwidth allocation method based on an orthogonal frequency division multiplexing (OFDM) system, which mainly solves the problems of service flow access control and system bandwidth resource allocation in the OFDM system. The method of the invention essentially comprises the following steps: (1) carrying out access control according to the management information of dynamic service flow and generating a bandwidth-reserved distribution list; (2) distributing the bandwidth-reserved according to the bandwidth-reserved distribution list; and (3) distributing the rest bandwidth according to a weight factor configuration table. The method provided by the invention not only effectively improves the use efficiency of the system resources, but also ensures fairness among a plurality of service types and prevents 'starvation' phenomenon caused by that the bandwidth cannot be obtained due to the comparatively low priority of users.

Description

A kind of service flow access control and bandwidth allocation methods based on ofdm system

Technical field

The present invention relates to a kind of broadband access technology, relate in particular to service flow access control and bandwidth allocation methods in a kind of MAC layer (MAC) of ofdm system based on ofdm system (OFDM).

Background technology

The IEEE802.16 standard has adopted the physical-layer techniques based on OFDM (OFDM).This standard criterion the physical layer (PHY) and the MAC layer (MAC) of air interface of system.

After the successful access network of subscriber station SS (or MS), can set up corresponding service flow the data business is carried transmission.Service flow is a kind of unidirectional data flow, it has defined one group of QOS parameter that satisfies the quality of services for users requirement and has comprised maximum bandwidth, minimum reserved bandwidth, the maximum delay etc. of continuing, and requires to be divided into 4 kinds of types of service according to different QOS: unsolicited grant service (UGS), real-time polling service (rtPS), non-real-time polling service (nrtPS) and Best-Effort service (BE).They reduce successively to the requirement of QOS.After user success access network, can increase that (DSA), dynamic service flow are revised (DSC), dynamic service flow deletion (DSD) message is managed dynamically to service flow by dynamic service flow.

As mentioned above, the user just is presented as the defined QOS parameter of service flow to the requirement of QoS.Existing service flow connection control method all can not guarantee in the service quality of business and improve between the system bandwidth level of resources utilization and obtain good balance.Perhaps, will inevitably cause some professional QOS to require and to be met like this for the utilization ratio that improves system resource makes that the service flow number that inserts in the system is too much.Perhaps overemphasize professional service quality, can cause the level of resources utilization of system not high again.Secondly, existing service dispatching and bandwidth allocation algorithm all are based on the scheduling of priority and distribute thought, especially under the heavier situation of the business load of high priority, can seize the bandwidth of lower-priority traffic, can occur lower-priority traffic under the serious situation and can not get bandwidth all the time and the phenomenon of " dying of hunger ".

Summary of the invention

The object of the present invention is to provide a kind of service flow access control and bandwidth allocation methods based on ofdm system.

A kind of service flow access control and bandwidth allocation methods based on ofdm system provided by the invention may further comprise the steps:

Step (1) service flow access control also generates the bandwidth reserved allocation table;

Step (2) is according to bandwidth reserved allocation table allocation bandwidth reserved;

Step (3) is distributed remaining bandwidth according to the weight factor allocation list.

Aforesaid method, wherein, step (1) further comprises:

The bandwidth reserved of computing system total bandwidth, system's aggregate reservation bandwidth, each service flow correspondence and with the bandwidth reserved BW_res of each service flow correspondence (i j) puts into the bandwidth reserved allocation table.

Aforesaid method, wherein,

Step 1.1 computing system total bandwidth is according to the subchannel number Ch_num and the number of symbols Sym_num of sub-frame of uplink, calculate its OFDMA time slot sum, and according to this time slot sum calculating current overall system bandwidth BW_total=(Ch_num*Sym_num/2) * Bytes_per_slot (i), Bytes_per_slot (i) is the maximum open ended Byte numbers of each time slot;

The step of the bandwidth reserved of step 1.2. computing system aggregate reservation bandwidth and each service flow correspondence is as follows: the system aggregate reservation bandwidth of setting up departments is BW_res, the bandwidth reserved size of the j bar service flow of i the subscriber station SS that has existed in the system is BW_res (i, j), then in the system bandwidth reserved to service flow be calculated as follows:

(a) if the fixing unsolicited grant service UGS of bit rate, its bandwidth reserved can directly be set at this business itself lasting bandwidth: the BW_res of maximum (i, j)=BW_max (i, j);

(b) if the real-time polling service rtPS of rate-compatible, the maximum that this professional bandwidth reserved equals this business itself continue bandwidth: BW_res (i, j)=BW_max (i, j);

(c) if the non-real-time polling service nrtPS of non-real-time service rate-compatible, this professional bandwidth reserved can be set at minimum reserved bandwidth: BW_res (i, j)=BW_min (i, j);

(d) if Best-Effort service BE, its bandwidth reserved can be made as 0, promptly BW_res (i, j)=0, the aggregate reservation bandwidth of system is: $\mathrm{BW}\_\mathrm{res}=\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}\mathrm{BW}\_\mathrm{res}(i,j);$

Step 1.3 is waited for new service flow access control request message, if being dynamic service flow, request message increases request message DSA, then according to described step (a) (b) (c) bandwidth reserved size of (d) calculating this service request be BW_res_req (i), and the BW_res of new business (i, j)=0, change step 1.6, otherwise continue to carry out;

If step 1.4 request message is dynamic service flow modify request messages DSC, to make amendment to the service flow that has originally existed, then according to described step (a) (b) (c) bandwidth reserved size of (d) calculating this service request be BW_res_req (i), searching original bandwidth reserved size according to service flow ID in the bandwidth reserved allocation table obtains: BW_res (i, j), change step 1.6, otherwise continue to carry out;

Step 1.5 request message is dynamic service flow deletion request message DSD, delete the service flow that has originally existed, then according to the service flow ID in the message, searching original bandwidth reserved size in the bandwidth reserved allocation table obtains: BW_res (i, j), if BW_res_req (i)=0 changes step 1.7;

Step 1.6 is carried out access control, getting the total bandwidth reserved of system according to as above step is BW_res, the bandwidth reserved of new requested service is BW_res_req (i), the total bandwidth of system is BW_total, if BW_res+BW_res_req (i)-BW_res (i, j)＜=and BW_total, then allow to insert this service flow, continue to carry out; Otherwise refuse the increase or the modification of this service flow, change step 1.3;

The bandwidth reserved that step 1.7 update system is total: BW_res=BW_res+BW_res_req (i)-BW_res (i, j), upgrade the bandwidth reserved allocation table, if DSA message then increases relevant entries, if DSC message, then revise corresponding list item, if DSD message is then deleted corresponding list item, change step 1.3 and continue to carry out.

Aforesaid method, wherein, step (2) further comprises:

Step 2.1 is in the beginning of every frame, collect the bandwidth request of each subscriber station SS, and in the bandwidth reserved allocation table that step (1) generates, search the bandwidth reserved of this service flow correspondence according to the service flow of correspondence sign SFID, be that benchmark is the bandwidth request allocation bandwidth reserved of subscriber station SS with this bandwidth reserved;

Step 2.2 bandwidth reserved assigns, the statistical system remaining bandwidth:

$\mathrm{BW}\_\mathrm{left}=\mathrm{BW}\_\mathrm{total}-\underset{i=k}{\mathrm{\Σ}}\underset{j=q}{\mathrm{\Σ}}\mathrm{BW}\_\mathrm{res}(i,j),k,q$ Expression has the subscriber station SS of bandwidth request and the quantity of service flow respectively.

Aforesaid method, wherein, step (3) further comprises:

Step 3.1 judges according to the remaining bandwidth BW_left of system of statistics in the step (2), if BW_left=0 then change step 3.8, otherwise continue to carry out;

Each professional bandwidth request bandwidth factor B of step 3.2 calculating (i, j), promptly each professional residue bandwidth on demand accounts for the ratio of total surplus bandwidth on demand: $B(i,j)=(\mathrm{BW}\_\mathrm{req}(i,j)-\mathrm{BW}\_\mathrm{res}(i,j))/\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}(\mathrm{BW}\_\mathrm{req}(i,j)-\mathrm{BW}\_\mathrm{res}(i,j));$

Step 3.3 is set each professional priority factors Q (i, j), occurrence is as follows according to each professional type in the system and professional corresponding QOS parameter-definition: UGS＞rtPS＞nrtPS＞BE, for the business of same type, give higher priority factor to the business that delay requirement is higher;

Step 3.4 is calculated each professional link factor L (i, j), the one-period timer is set in system, the carrier-in-interference noise ratio cinr of each link of periodic measurement, a carrier-in-interference noise ratio of Dynamic Maintenance cinr link factor allocation list, up-downgoing channel carrier wave interference noise ratio cinr according to systematic survey, dynamically adjust carrier-in-interference noise ratio cinr link factor allocation list, give the different link factors to each business, carrier-in-interference noise ratio cinr value is bigger, the link corresponding factor is bigger, otherwise, less;

The B that step 3.5 calculates according to step 3.2,3.3,3.4 (i, j), Q (i, j), L (i, j), calculate each professional weight factor α (i, j)=B (i, j) * Q (i, j) * (i j), generates the weight factor allocation list to L;

Step 3.6 is distributed system's remaining bandwidth according to the weight factor allocation list between each business, the remaining bandwidth that j the service flow of i SS is assigned to is:

$\mathrm{BW}\_\mathrm{left}(i,j)=\mathrm{BW}\_\mathrm{left}*(\mathrm{\α}(i,j)/\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}\mathrm{\α}(i,j));$

If the remaining bandwidth BW_left of step 3.7 system＞0 then jump to step 3.6 and continue to distribute, otherwise continue;

Bandwidth reserved BW_res (the i that step 3.8 obtains according to each business, j) and distribute the remaining bandwidth BW_left (i obtain, j) calculate the total bandwidth BW (i that each business obtains, j)=BW_res (i, j)+(i j), is a unit with SS to BW_left, all of its correspondence are connected the bandwidth get separately add up, obtain each SS divide bandwidth $\mathrm{BW}\_\mathrm{ss}\left(i\right)=\underset{j}{\mathrm{\Σ}}\mathrm{BW}(i,j),$ And then can try to achieve its timeslot number Slots_ss (i) that takies=BW_ss (i)/Bytes_per_slot (i), and generating up access slot allocation table UL-MAP, this allocated bandwidth finishes.

The present invention is directed to prior art in the deficiency and the problem that occur aspect service flow access and the allocated bandwidth, a kind of service flow access control and the bandwidth allocation methods based on ofdm system that provide are in the utilization ratio that guarantees to improve when each professional QOS requires system resource.The method of the invention has not only satisfied the utilization ratio that each professional quality of service requirement in the system has also effectively improved system resource, wherein in distributing, introduces remaining bandwidth the calculating of weight factor, make allocated bandwidth more flexible, better adapted to the flexible and changeable characteristic of future communications system business, Processing Algorithm is simple simultaneously, is easy to realize.

Description of drawings

Fig. 1 is service flow access control of the present invention and allocated bandwidth theory diagram;

Fig. 2 is a service flow connection control method flow chart of the present invention;

Fig. 3 is a bandwidth allocation methods flow chart of the present invention.

Embodiment

Below in conjunction with the drawings and specific embodiments, the invention will be further described.

The invention provides that service flow in a kind of MAC layer that is used for ofdm system inserts and the implementation method of allocated bandwidth.This method is according to current each professional scheduling type, QoS parameter, and channel quality etc. are realized the access control and the allocated bandwidth of service flow.This method can guarantee the professional fairness of accepting service, has improved the capacity of system preferably, and Processing Algorithm is simple simultaneously, is easy to realize.

The theory diagram of the inventive method as shown in Figure 1, this method combines the access control and the allocated bandwidth of service flow, after subscriber station (SS) networks successfully, subscriber station (SS) or base station (BS) can initiate dynamic service flow increases request (DSA), and perhaps situation about having existed in service flow issues that dynamic service flow is revised request (DSC) or dynamic service flow removal request (DSD) is carried out the demand that dynamic management adapts to business to service flow.After each new business arrived, BS should generate the bandwidth reserved allocation table according to the type of service of this service flow, and carries out access control according to this bandwidth reserved, distributes bandwidth reserved and distributes remaining bandwidth.

Introduce know-why of the present invention below in conjunction with a specific embodiment of the present invention.Present embodiment is mainly with the example that is assigned as of upstream bandwidth.

In order to discuss conveniently, suppose to insert SS_num SS, wherein i SS set up the individual connection of Conn_num (i), i=1 wherein, 2 ..., SS_num.If among i SS j minimum that connects corresponding service flow guarantee speed be TR_min (i, j), maximum continue speed be TR_max (i, j), unit is bit/s, j=1 wherein, 2 ..., Conn_num (i).If Frame_duration is the time interval of consecutive frame, unit is ms.If the above-mentioned minimum that is connected in each frame guarantees speed and the maximum bandwidth that continues the speed correspondence and is respectively BW_min (i, j) and BW_max (i, j), unit is Byte, then have BW_min (i, j)=Frame_duration*TR_min (i, j)/8000, BW_max (i, j)=Frame_duration*TR_max (i, j)/8000.In addition, according to modulation coding mode and the repeated encoding indication of i SS, establish its each time slot and can hold the individual Byte of Bytes_per_slot (i) at most.Then specific embodiment is as follows:

(1) service flow access control and the method flow diagram that generates the bandwidth reserved allocation table as shown in Figure 2, the specific implementation process of this method comprises:

1, computing system total bandwidth:

Subchannel number Ch_num and number of symbols Sym_num according to sub-frame of uplink, calculate its OFDMA time slot sum, and according to this time slot sum calculating current overall system bandwidth BW_total=(Ch_num*Sym_num/2) * Bytes_per_slot (i), unit is Byte.

2, computing system aggregate reservation bandwidth:

The system aggregate reservation bandwidth of setting up departments is BW_res, the bandwidth reserved size of i the SS j bar service flow that has existed in the system be BW_res (i, j), then the bandwidth reserved to service flow is calculated as follows in the system:

(1) if the fixing unsolicited grant service (UGS) of bit rate, system can distribute bandwidth for it in fixing mandate at interval, need not can not be to system's bandwidth application, so can directly being set at the maximum of this business itself, its bandwidth reserved continues bandwidth: BW_res (i, j)=and BW_max (i, j);

(2) if the real-time polling service of rate-compatible (rtPS), consider the requirement of this business real-time, so the bandwidth of this service request also should farthest be met should business the bandwidth reserved maximum that also should equal this business itself continue bandwidth: BW_res (i, j)=and BW_max (i, j);

(3) if the non-real-time polling service of non-real-time service rate-compatible (nrtPS), it is enough big to set this professional buffering area in this method, allow packet to wait for indefinite duration in buffering area, bandwidth reserved that then should business can be set at minimum reserved bandwidth: BW_res (i, j)=and BW_min (i, j);

(4) if Best-Effort service (BE) does not require QOS, so its bandwidth reserved can be made as 0, promptly BW_res (i, j)=0.

As mentioned above, the aggregate reservation bandwidth that obtains system is: $\mathrm{BW}\_\mathrm{res}=\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}\mathrm{BW}\_\mathrm{res}(i,j).$ And with the bandwidth reserved BW_res of each service flow correspondence (i j) puts into the bandwidth reserved allocation table.

3, wait for new management service flow message (DSA/DSC/DSD).If being dynamic service flow, request message increases request message (DSA), then calculate the big or small BW_res_req (i) of being of bandwidth reserved of this service request according to step described in the step 2 (1) (2) (3) (4), and the BW_res of new business (i, j)=0 (promptly in the bandwidth reserved allocation table not to this new business bandwidth reserved) changes step 6.Otherwise continue to carry out.

If 4 request messages are dynamic service flow modify request messages (DSC), to make amendment to the service flow that has originally existed, then calculate the big or small BW_res_req (i) of being of bandwidth reserved of this service request according to step described in the step 2 (1) (2) (3) (4), searching original bandwidth reserved size according to service flow ID in the bandwidth reserved allocation table obtains: BW_res (i, j), change step 6, otherwise continue to carry out.

5, request message is dynamic service flow deletion request message (DSD), delete the service flow that has originally existed, then according to the service flow ID in the message, searching original bandwidth reserved size in the bandwidth reserved allocation table obtains: BW_res (i, j), if BW_res_req (i)=0 changes step 7.

6, carry out access control (promptly by audit), getting the total bandwidth reserved of system according to as above step is BW_res, and the bandwidth reserved of new requested service is BW_res_req (i), and the total bandwidth of system is BW_total.If BW_res+BW_res_req (i)-BW_res (i, j)＜=BW_total then allows to insert this service flow, otherwise refuse the increase or the modification of this service flow, change step 3, continue to carry out.

7, the total bandwidth reserved of update system: BW_res=BW_res+BW_res_req (i)-BW_res (i, j), upgrade the bandwidth reserved allocation table, if DSA message then increases relevant entries, if DSC message, then revise corresponding list item, if DSD message is then deleted corresponding list item, change step 3 and continue to carry out.

The distribution of system bandwidth is divided into that step (two) bandwidth reserved distributes and step (three) remaining bandwidth distributed for two steps greatly, concrete method flow diagram as shown in Figure 3, the specific implementation process of system bandwidth distribution comprises the steps:

(2) distribute bandwidth reserved further to comprise:

1, in the beginning of every frame, collect the bandwidth request of each SS, and in the bandwidth reserved allocation table that step () generates, search the bandwidth reserved of this service flow correspondence according to the service flow of correspondence sign SFID, be that benchmark is the bandwidth request allocation bandwidth reserved of SS with this bandwidth reserved.

2, bandwidth reserved assigns, the statistical system remaining bandwidth:

$\mathrm{BW}\_\mathrm{left}=\mathrm{BW}\_\mathrm{total}-\underset{i=k}{\mathrm{\Σ}}\underset{j=q}{\mathrm{\Σ}}\mathrm{BW}\_\mathrm{res}(i,j)$ (k, q represent to have the SS of bandwidth request and the quantity of service flow respectively).

(3) distribute remaining bandwidth further to comprise:

1, the remaining bandwidth BW_left of system according to statistics in the step (two) judges, if BW_left=0 then change step 8, otherwise continue to carry out.

2, calculate each professional bandwidth request bandwidth factor B (i, j), promptly each professional residue bandwidth on demand (being the surplus value that bandwidth on demand deducts bandwidth reserved) accounts for the ratio of total surplus bandwidth on demand:

$B(i,j)=(\mathrm{BW}\_\mathrm{req}(i,j)-\mathrm{BW}\_\mathrm{res}(i,j))/\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}(\mathrm{BW}\_\mathrm{req}(i,j)-\mathrm{BW}\_\mathrm{res}(i,j))$

3, (i, j), occurrence is as follows according to each professional type in the system and professional corresponding QOS parameter-definition: UGS＞rtPS＞nrtPS＞BE to set each professional priority factors Q.For the business of same type, give higher priority factor to the business that delay requirement is higher.

4, calculate each professional link factor L (i, j), the one-period timer is set in system, the carrier-in-interference noise ratio cinr of each link of periodic measurement, a carrier-in-interference noise ratio of Dynamic Maintenance cinr link factor allocation list as much as possible truly reflects the actual conditions of link.According to the up-downgoing channel carrier wave interference noise ratio cinr of systematic survey, dynamically adjust carrier-in-interference noise ratio cinr link factor allocation list, give the different link factors to each business.Carrier-in-interference noise ratio cinr value is bigger, and the link corresponding factor is bigger, otherwise, less.

5, the B that calculates according to step 2,3,4 (i, j), Q (i, j), L (i, j), calculate each professional weight factor α (i, j)=B (i, j) * Q (i, j) * (i j), generates the weight factor allocation list to L;

6, according to the weight factor allocation list system's remaining bandwidth is distributed between each business, the remaining bandwidth that j the service flow of i SS is assigned to is:

$\mathrm{BW}\_\mathrm{left}(i,j)=\mathrm{BW}\_\mathrm{left}*(\mathrm{\α}(i,j)/\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}\mathrm{\α}(i,j)).$

If the 7 remaining bandwidth BW_left of system＞0 then jump to step (6) and continue to distribute, otherwise continue.

8, the bandwidth reserved BW_res that obtains according to each business (i, j) and distribute the remaining bandwidth BW_left obtain (i, j) calculate the total bandwidth BW that each business obtains (i, j)=BW_res (i, j)+BW_left (i, j).With SS is unit, all of its correspondence is connected the bandwidth get separately add up, obtain each SS divide bandwidth $\mathrm{BW}\_\mathrm{ss}\left(i\right)=\underset{j}{\mathrm{\Σ}}\mathrm{BW}(i,j),$ And then can try to achieve its timeslot number Slots_ss (i) that takies=BW_ss (i)/Bytes_per_slot (i), and generating up access slot allocation table UL-MAP, this allocated bandwidth finishes.

Above embodiment only limits to illustrate service flow access control of the present invention and uplink bandwidth allocation method, but the content that is not limited to embodiment of the present invention.According to the inventive method, those of ordinary skill in the art can realize the present invention at an easy rate, or is improved by other modes, will be appreciated that all any improvement that does not break away from inventive concept all belong to protection scope of the present invention.

Claims (5)

1. service flow access control and bandwidth allocation methods based on an ofdm system is characterized in that may further comprise the steps:

Step (1) service flow access control also generates the bandwidth reserved allocation table;

Step (2) is according to bandwidth reserved allocation table allocation bandwidth reserved;

Step (3) is distributed remaining bandwidth according to the weight factor allocation list.

2. method according to claim 1 is characterized in that: step (1) further comprises:

The bandwidth reserved of computing system total bandwidth, system's aggregate reservation bandwidth, each service flow correspondence and with the bandwidth reserved BW_res of each service flow correspondence (i j) puts into the bandwidth reserved allocation table.

3. method according to claim 2 is characterized in that:

Step 1.1 computing system total bandwidth is according to the subchannel number Ch_num and the number of symbols Sym_num of sub-frame of uplink, calculate its OFDMA time slot sum, and according to this time slot sum calculating current overall system bandwidth BW_total=(Ch_num*Sym_num/2) * Bytes_per_slot (i), Bytes_per_slot (i) is the maximum open ended Byte numbers of each time slot;

The step of the bandwidth reserved of step 1.2. computing system aggregate reservation bandwidth and each service flow correspondence is as follows: the system aggregate reservation bandwidth of setting up departments is BW_res, the bandwidth reserved size of the j bar service flow of i the subscriber station SS that has existed in the system is BW_res (i, j), then in the system bandwidth reserved to service flow be calculated as follows:

(a) if the fixing unsolicited grant service UGS of bit rate, its bandwidth reserved can directly be set at this business itself lasting bandwidth: the BW_res of maximum (i, j)=BW_max (i, j);

(b) if the real-time polling service rtPS of rate-compatible, the maximum that this professional bandwidth reserved equals this business itself continue bandwidth: BW_res (i, j)=BW_max (i, j);

(c) if the non-real-time polling service nrtPS of non-real-time service rate-compatible, this professional bandwidth reserved can be set at minimum reserved bandwidth: BW_res (i, j)=BW_min (i, j);

(d) if Best-Effort service BE, its bandwidth reserved can be made as 0, promptly BW_res (i, j)=0, the aggregate reservation bandwidth of system is: $\mathrm{BW}\_\mathrm{res}=\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}\mathrm{BW}\_\mathrm{res}(i,j);$

Step 1.3 is waited for new service flow access control request message, if being dynamic service flow, request message increases request message DSA, then according to described step (a) (b) (c) bandwidth reserved size of (d) calculating this service request be BW_res_req (i), and the BW_res of new business (i, j)=0, change step 1.6, otherwise continue to carry out;

If step 1.4 request message is dynamic service flow modify request messages DSC, to make amendment to the service flow that has originally existed, then according to described step (a) (b) (c) bandwidth reserved size of (d) calculating this service request be BW_res_req (i), searching original bandwidth reserved size according to service flow ID in the bandwidth reserved allocation table obtains: BW_res (i, j), change step 1.6, otherwise continue to carry out;

Step 1.5 request message is dynamic service flow deletion request message DSD, delete the service flow that has originally existed, then according to the service flow ID in the message, searching original bandwidth reserved size in the bandwidth reserved allocation table obtains: BW_res (i, j), if BW_res_req (i)=0 changes step 1.7;

Step 1.6 is carried out access control, getting the total bandwidth reserved of system according to as above step is BW_res, the bandwidth reserved of new requested service is BW_res_req (i), the total bandwidth of system is BW_total, if BW_res+BW_res_req (i)-BW_res (i, j)＜=and BW_total, then allow to insert this service flow, continue to carry out; Otherwise refuse the increase or the modification of this service flow, change step 1.3;

The bandwidth reserved that step 1.7 update system is total: BW_res=BW_res+BW_res_req (i)-BW_res (i, j), upgrade the bandwidth reserved allocation table, if DSA message then increases relevant entries, if DSC message, then revise corresponding list item, if DSD message is then deleted corresponding list item, change step 1.3 and continue to carry out.

4. method according to claim 1 is characterized in that step (2) further comprises:

Step 2.1 is in the beginning of every frame, collect the bandwidth request of each subscriber station SS, and in the bandwidth reserved allocation table that step (1) generates, search the bandwidth reserved of this service flow correspondence according to the service flow of correspondence sign SFID, be that benchmark is the bandwidth request allocation bandwidth reserved of subscriber station SS with this bandwidth reserved;

Step 2.2 bandwidth reserved assigns, the statistical system remaining bandwidth:

$\mathrm{BW}\_\mathrm{left}=\mathrm{BW}\_\mathrm{total}-\underset{i=k}{\mathrm{\Σ}}\underset{j=q}{\mathrm{\Σ}}\mathrm{BW}\_\mathrm{res}(i,j),$ K, q represent that respectively the subscriber station SS of bandwidth request and the quantity of service flow are arranged.

5. method according to claim 1 is characterized in that step (3) further comprises:

Step 3.1 judges according to the remaining bandwidth BW_left of system of statistics in the step (2), if BW_left=0 then change step 3.8, otherwise continue to carry out;

Each professional bandwidth request bandwidth factor B of step 3.2 calculating (i, j), promptly each professional residue bandwidth on demand accounts for the ratio of total surplus bandwidth on demand: $B(i,j)=(\mathrm{BW}\_\mathrm{req}(i,j)-\mathrm{BW}\_\mathrm{res}(i,j))/\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}(\mathrm{BW}\_\mathrm{req}(i,j)-\mathrm{BW}\_\mathrm{res}(i,j));$

Step 3.3 is set each professional priority factors Q (i, j), occurrence is as follows according to each professional type in the system and professional corresponding QOS parameter-definition: UGS＞rtPS＞nrtPS＞BE, for the business of same type, give higher priority factor to the business that delay requirement is higher;

Step 3.4 is calculated each professional link factor L (i, j), the one-period timer is set in system, the carrier-in-interference noise ratio cinr of each link of periodic measurement, a carrier-in-interference noise ratio of Dynamic Maintenance cinr link factor allocation list, up-downgoing channel carrier wave interference noise ratio cinr according to systematic survey, dynamically adjust carrier-in-interference noise ratio cinr link factor allocation list, give the different link factors to each business, carrier-in-interference noise ratio cinr value is bigger, the link corresponding factor is bigger, otherwise, less;

The B that step 3.5 calculates according to step 3.2,3.3,3.4 (i, j), Q (i, j), L (i, j), calculate each professional weight factor α (i, j)=B (i, j) * Q (i, j) * (i j), generates the weight factor allocation list to L;

Step 3.6 is distributed system's remaining bandwidth according to the weight factor allocation list between each business, the remaining bandwidth that j the service flow of i SS is assigned to is:

$\mathrm{BW}\_\mathrm{left}(i,j)=\mathrm{BW}\_\mathrm{left}*(\mathrm{\α}(i,j)/\underset{i}{\mathrm{\Σ}}\underset{j}{\mathrm{\Σ}}\mathrm{\α}(i,j));$

If the remaining bandwidth BW_left of step 3.7 system＞0 then jump to step 3.6 and continue to distribute, otherwise continue;

Bandwidth reserved BW_res (the i that step 3.8 obtains according to each business, j) and distribute the remaining bandwidth BW_left (i obtain, j) calculate the total bandwidth BW (i that each business obtains, j)=BW_res (i, j)+(i j), is a unit with SS to BW_left, all of its correspondence are connected the bandwidth get separately add up, obtain each SS divide bandwidth $\mathrm{BW}\_\mathrm{ss}\left(i\right)=\underset{j}{\mathrm{\Σ}}\mathrm{BW}(i,j),$ And then can try to achieve its timeslot number Slots_ss (i) that takies=BW_ss (i)/Bytes_per_slot (i), and generating up access slot allocation table UL-MAP, this allocated bandwidth finishes.

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