CN100384293C

CN100384293C - Call admission control method

Info

Publication number: CN100384293C
Application number: CNB2004100741166A
Authority: CN
Inventors: 张建伟
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2004-08-31
Filing date: 2004-08-31
Publication date: 2008-04-23
Anticipated expiration: 2024-08-31
Also published as: CN1744755A

Abstract

The present invention discloses a calling admittance control method, wherein the processing procedures comprise: a. a base station controller (RNC) receives a calling request, and obtains the existing service information of a current access subzone; b. whether the request reason of the current calling is the reconfiguration of signal channels is judged, and if the reason is the reconfiguration of the signal channels, the step c is carried out; or else the step d is carried out; c. whether a current request access service requires to enhance the service performance requirement (QoS) of a downlink is judged, and if the current request access service requires to enhance the service performance requirement (QoS) of the downlink, the step d is carried out; or else the calling request is accepted, and the current processing is ended; d. whether the downlink can be coupled in the current calling is judged according to the calling request, the existing service information of the downlink of the current access subzone and the prearranged load threshold of the subzone downlink, and if the downlink can be coupled in the current calling, the calling request is accepted; or else the calling request is rejected. The present invention also discloses three calling admittance control methods, and the use of the four methods provided by the present invention can cause RNC to effectively use system resource to carry out admission control against different calling request reasons.

Description

Call admission control method

Technical Field

The present invention relates to a call control technology, particularly to a call admission control method applied to a base station controller (RNC) in a Wideband Code Division Multiple Access (WCDMA) system.

Background

The WCDMA system is a cellular mobile communication system with advanced performance, and the RNC is used as the control core of the radio resource management of the WCDMA system to manage and schedule the radio resources of the whole system.

Among them, the power resource of the air interface is one of the very important radio resources. In a WCDMA system, when a new service is admitted, the total interference level received by the system, i.e. the total wideband received power (RTWP), will increase for the uplink; for the downlink, the downlink transmission power of the base station, i.e. the carrier transmission power (TCP), will also be increased. In an overloaded system, the rise of RTWP or TCP may cause the call quality to be degraded, and in severe cases, a large area call drop may be caused.

Currently, in order to ensure the communication quality of the original service, the cell coverage and the resource utilization rate in the system, the RNC has adopted a certain admission control technology to control the cell access service. When a mobile user initiates a new call or applies for handover in a new cell, or adds a new service in an existing call process, or performs channel reconfiguration on an existing service, the RNC performs admission control. In a WCDMA system, admission control is performed separately in uplink and downlink, i.e. the whole admission control is divided into two parts: and the RNC can access the call request only when the uplink and downlink admission control judges that the current call can be accessed. In the prior art, when performing uplink or downlink admission control, a single comparison method is adopted for processing, and the following schemes are generally adopted: firstly, setting a user number threshold, and accessing a new user under the condition that the user number does not exceed the threshold; otherwise, refusing to access the new user; estimating the load level of the system after the new service is accessed, then comparing the load level estimation value with a preset load threshold, and if the load level estimation value does not exceed the load threshold, receiving the access request; otherwise, refusing the admission request; for example, setting a total downlink transmission power threshold of a base station, obtaining the current downlink transmission power of the base station, summing the downlink transmission power with a power estimated value set for a new service applying admission, if the obtained power sum is less than the total downlink transmission power threshold of the base station, accessing the new service, otherwise, refusing to access the new service; and thirdly, setting other thresholds according to the management requirement to compare to determine whether to access the new service.

However, the existing admission control methods still have some problems in their overall and detailed handling:

first, the prior art does not flexibly manage the entire admission control process, does not consider the different requirements for cell uplink and downlink admission control in different network planning stages, and can only be accessed when all call requests are admitted by decision in both uplink and downlink, so that the admission control function of the RNC cannot be flexibly applied to various network environments. In addition, in the actual implementation process of the RNC, the admission control algorithm is unstable, and the instability of the admission control of any link in the uplink and the downlink will cause misjudgment, so that the stability of the admission control cannot be ensured by dynamically controlling the part with unstable function. In addition, some cells can predict that their uplink or downlink load level will not exceed the load threshold in a certain network planning stage, and then it becomes meaningless to perform uplink or downlink admission control on them.

Secondly, the prior art does not control the service characteristics of the call request for different reasons. Generally, there are three call request reasons: handover, channel reconfiguration and new service access. The prior art does not consider the factor of the reason of the call request, and performs uniform control on all call requests, so for some call requests, for example: channel reconfiguration requests with reduced QoS, etc., the access of which does not bring about a load level increase, and the admission control of which is not of practical significance, also wastes system resources to a certain extent. Here, the new service access includes: and the mobile user initiates a new call in a new cell, or adds a new service in the process of an existing call, and the like.

In addition, the prior art does not consider the demands of operators and users on different services and the expectations of service quality, and sets the same admission control load threshold for all services, so that some low-priority services affect the access of services with high priority. Such as: for a user, the priority of the switching service and the voice service is usually higher, and if the load thresholds of the voice service and other services are set to be the same value, the access of the data service with large data volume fluctuation will affect the call quality of the original voice service or make a new voice service inaccessible.

In summary, the existing call admission scheme cannot manage the system flexibly, cannot control the system efficiently according to different call requests, cannot guarantee the communication quality of high-priority services, and cannot fully utilize the limited wireless resources of the system to meet the service requirements of users.

Disclosure of Invention

In view of the above, the main objective of the present invention is to provide a call admission control method, which enables an RNC to effectively utilize system resources for downlink admission control for different call request reasons.

Another objective of the present invention is to provide a call admission control method, which enables an RNC to effectively utilize system resources for uplink admission control for different call request reasons.

Still another objective of the present invention is to provide a call admission control method, which enables an RNC to flexibly start an admission control procedure of an uplink/downlink, and to process according to different call request reasons, thereby ensuring stability and efficiency of admission control.

Another objective of the present invention is to provide a call admission control method, which enables an RNC to flexibly configure an admission control flow, and to process the admission control flow according to different call request reasons, thereby effectively utilizing system resources and ensuring the stability of admission control.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

the invention discloses a call admission control method, which comprises the following processing steps:

RNC receives call request to obtain the present service information of current request access cell;

b. judging whether the request reason of the current call is channel reconfiguration, if so, executing the step c; otherwise, executing step d;

c. d, judging whether the current request access service requires to improve the service performance requirement (QoS) of the downlink, if so, executing the step d; otherwise, the call request is accepted, and the current processing is finished;

d, RNC judges whether the down link can be accessed to the current call according to the call request, the existing service information of the current request access cell down link and the preset load threshold of the cell down link, if yes, the call request is accepted; otherwise, the call request is rejected.

Wherein, the step c or step d further comprises before the accepting the call request:

e. judging the request reason of the current call: if the switching is the same frequency switching, the call request is accepted, and the current processing is finished; if the channel reconfiguration is carried out, executing the step f; if the reason is other than the same frequency switching and channel reconfiguration, executing step g;

f. judging whether the current request access service requires to improve the QoS of the uplink, if so, executing the step g; otherwise, the call request is accepted, and the current processing is finished;

the RNC judges whether the uplink can be accessed to the current call according to the call request, the existing service information of the uplink of the current request access cell and the preset load threshold of the uplink of the cell, and if so, the RNC receives the call request; otherwise, rejecting the call request and ending the current process.

Wherein the cell downlink load threshold comprises: a switching service load threshold and a non-switching service load threshold;

before the determining whether the downlink can access the current call, the method further comprises: judging whether the request reason of the current call is switching, if so, adopting a switching service load threshold; otherwise, adopting a non-switching service load threshold.

Wherein the handover traffic load threshold is higher than the non-handover traffic load threshold.

Wherein the cell downlink load threshold comprises: a switching service load threshold, a voice service load threshold and a non-switching and voice service load threshold; before the determining whether the downlink can access the current call, the method further comprises: judging the request reason and the service type of the current call according to the call request, and if the current call is a switching service, adopting a switching service load threshold; if the voice service is the voice service, adopting a voice service load threshold; if the traffic is other than the switching traffic and the voice traffic, the non-switching and voice traffic load thresholds are adopted.

Wherein the voice traffic load threshold is higher than the non-handover and voice traffic load thresholds and lower than the handover traffic load threshold.

Wherein, a common channel load reserved value is preset for each cell; before the determining whether the downlink can access the current call, the method further comprises: and taking the difference between the load threshold and the public channel load reserved value of the current cell as the load threshold value for carrying out admission control judgment on the cell.

The invention also discloses a call admission control method, which comprises the following processing steps:

the RNC receives a call request and acquires the existing service information of the current request access cell;

b1. judging the request reason of the current call, if the call is the same frequency switching, receiving the call request, and ending the current processing; if it is a channel reconfiguration, performing step c 1; if it is for other reasons than intra-frequency handover and channel reconfiguration, step d1 is performed.

c1. Judging whether the current request access service requires to improve the QoS of the uplink, if so, executing step d 1; otherwise, the call request is accepted, and the current processing is finished;

d1, RNC judges whether the up link can be accessed to the current call according to the call request, the existing service information of the up link of the current request access cell and the preset up link load threshold of the cell, if so, the call request is accepted; otherwise, the call request is rejected.

Wherein the accepting the call request further comprises:

e1. judging whether the request reason of the current call is channel reconfiguration, if so, executing step f 1; otherwise, executing step g 1;

f1. judging whether the current request access service requires to improve the QoS of the downlink, if so, executing step g 1; otherwise, the call request is accepted, and the current processing is finished;

the RNC judges whether the downlink can be accessed into the current call or not according to the call request, the existing service information of the downlink of the current access cell and the preset load threshold of the downlink of the cell, and if so, the RNC receives the call request; otherwise, rejecting the call request and ending the current process.

Wherein the downlink cell load threshold comprises: a switching service load threshold and a non-switching service load threshold;

the step of judging whether the downlink can be accessed to the current call further comprises the steps of judging whether the request reason of the current call is switching, and if so, adopting a switching service load threshold; otherwise, adopting a non-switching service load threshold.

Wherein, a common channel load reserved value is preset for each cell; before the determining whether the downlink can access the current call, the method further comprises: and taking the difference between the downlink load threshold and the public channel load reserved value of the current cell as the load threshold value for carrying out admission control judgment on the cell.

The invention also discloses a call admission control method, wherein RNC sets admission control enabling parameters for each cell, and the processing steps comprise:

a2, RNC receives the call request and acquires the existing service information of the current request access cell; judging whether the cell requires uplink admission control according to the admission control enabling parameter of the cell, if so, executing step b 2; otherwise, the call request is accepted, and the current processing is finished; or,

judging whether the cell requires downlink admission control, if so, executing step e 2; otherwise, the call request is accepted, and the current processing is finished;

b2. judging the request reason of the current call, if the call is the same frequency switching, receiving the call request, and ending the current processing; if it is a channel reconfiguration, performing step c 2; if the reason is other than the same-frequency switching and channel reconfiguration, executing step d 2;

c2. judging whether the current request access service requires to improve the uplink QoS, if so, executing step d 2; otherwise, the call request is accepted, and the current processing is finished;

d2, RNC judges whether the up link can be accessed to the current call according to the call request, the existing service information of the up link of the current request access cell and the preset load threshold of the up link of the cell, if so, the call request is accepted, and the current processing is finished; otherwise, rejecting the call request and ending the current processing;

e2. judging whether the request reason of the current call is channel reconfiguration, if so, executing step f 2; otherwise, executing step g 2;

f2. judging whether the current request access service requires to improve the downlink QoS, if so, executing a step g 2; otherwise, the call request is accepted, and the current processing is finished;

the RNC judges whether the downlink can be accessed to the current call or not according to the call request, the existing service information of the downlink of the current request access cell and the preset load threshold of the downlink of the cell, and if so, the call request is accepted; otherwise, the call request is rejected.

In step a2, determining whether to perform uplink admission control; before the determining that the cell does not require uplink admission control and receives the call request, the method further includes:

a21. judging whether the cell requires downlink admission control according to the admission control enabling parameters of the cell, if so, executing step b 21; otherwise, the call request is accepted;

b21 judging whether the request reason of the current call is channel reconfiguration, if yes, executing step c 21; otherwise, executing step d 21;

c21. judging whether the current request access service requires to improve the QoS of the downlink, if so, executing step d 21; otherwise, the call request is accepted;

d21.RNC judges whether the down link can be accessed to the current call according to the call request, the existing service information of the current request access cell down link and the load threshold of the cell down link, if yes, the call request is accepted; otherwise, rejecting the call request and ending the current process.

In step a2, determining whether to perform downlink admission control; before the determining that the cell does not require downlink admission control and receives the call request, the method further includes:

e21. judging whether the cell requires uplink admission control according to the admission control enabling parameters of the cell, and if so, executing step f 21; otherwise, the call request is accepted;

f21. judging the request reason of the current call, if the call is the same frequency switching, receiving the call request; if it is a channel reconfiguration, performing step g 21; if the reason is other than the same-frequency switching and channel reconfiguration, executing step h 21;

g21. judging whether the current request access service requires to improve the QoS of the uplink, if so, executing a step h 21; otherwise, the call request is accepted;

the RNC judges whether the uplink can be accessed to the current call or not according to the call request, the existing service information of the uplink of the current request access cell and the load threshold of the uplink of the cell, and if so, the RNC receives the call request; otherwise, rejecting the call request and ending the current process.

Setting a public channel load reserved value for each cell; before the determining whether the downlink can access the current call, the method further comprises: and taking the difference between the downlink load threshold and the public channel load reserved value of the current cell as the load threshold value of the cell admission control judgment.

RNC receives the call request, judges whether the cell refuses to carry out admission control according to the admission control enabling parameter of the current request access cell, if so, accepts the call request and ends the current processing; otherwise, executing step b 3;

b3. acquiring the existing service information of the current request access cell, judging whether the cell requires uplink admission control according to the admission control enabling parameter of the cell, and if so, executing step c 3; otherwise, the call request is accepted, and the current processing is finished; or,

judging whether the cell requires downlink admission control, if so, executing step f 3; otherwise, the call request is accepted, and the current processing is finished;

c3. judging the request reason of the current call, if the call is the same frequency switching, receiving the call request, and ending the current processing; if it is a channel reconfiguration, performing step d 3; if the reason is other than the same-frequency switching and channel reconfiguration, executing step e 3;

d3. judging whether the current request access service requires to improve the uplink QoS, if so, executing step e 3; otherwise, the call request is accepted, and the current processing is finished;

the RNC judges whether the uplink can be accessed into the current call or not according to the call request, the existing service information of the uplink of the current request access cell and the preset load threshold of the uplink of the cell, if so, the RNC receives the call request and finishes the current processing; otherwise, rejecting the call request and ending the current processing;

f3. judging whether the request reason of the current call is channel reconfiguration, if so, executing step g 3; otherwise, executing step h 3;

g3. judging whether the current request access service requires to improve the downlink QoS, if so, executing a step h 3; otherwise, the call request is accepted, and the current processing is finished;

RNC judges whether the down link can be accessed to the current call according to the call request, the existing service information of the current request access cell down link and the preset load threshold of the cell down link, if so, the call request is accepted; otherwise, the call request is rejected.

In step b3, whether to perform uplink admission control is judged; before the determining that the cell does not require uplink admission control and receives the call request, the method further includes:

b31. judging whether the cell requires downlink admission control according to the admission control enabling parameter of the cell, if so, executing step c 31; otherwise, the call request is accepted;

c31. judging whether the request reason of the current call is channel reconfiguration, if so, executing step d 31; otherwise, executing step e 31;

d31. judging whether the current request access service requires to improve the QoS of the downlink, if so, executing step e 31; otherwise, the call request is accepted;

the RNC judges whether the downlink can be accessed to the current call or not according to the call request, the existing service information of the current request access cell downlink and the load threshold of the cell downlink, and if so, the call request is accepted; otherwise, rejecting the call request and ending the current process.

21. The method according to claim 19, wherein in step b3, it is determined whether to perform downlink admission control; before the determining that the cell does not require downlink admission control and receives the call request, the method further includes:

f31. judging whether the cell requires uplink admission control according to the admission control enabling parameters of the cell, and if so, executing step g 31; otherwise, the call request is accepted;

g31. judging the request reason of the current call, if the call is the same frequency switching, receiving the call request; if it is a channel reconfiguration, perform step h 31; if the reason is other than the same-frequency switching and channel reconfiguration, executing step i 31;

h31. judging whether the current request access service requires to improve the QoS of an uplink, if so, executing a step i 31; otherwise, the call request is accepted;

the RNC judges whether the uplink can be accessed into the current call or not according to the call request, the existing service information of the uplink of the current request access cell and the load threshold of the uplink of the cell, and if so, the call request is accepted; otherwise, rejecting the call request and ending the current process.

The key point of the invention is that: in the first method provided by the invention, when the downlink admission control is carried out, the RNC requests the direct admission of the call which is not required to be improved by the QoS channel reconfiguration. The second method provided by the invention directly receives the call request of channel reconfiguration which is requested because of same frequency switching or QoS not requiring improvement during uplink access control. In the third method, admission control enabling parameters are set for each cell, after receiving a call request, the RNC judges whether the current access cell requires uplink or downlink admission control according to the admission control enabling parameters, and if so, the RNC correspondingly performs the uplink or downlink admission control processing of the first or second method; otherwise the request is admitted directly. On the basis of the third method, the fourth method of the present invention further judges whether the current request access cell refuses to perform admission control according to the admission control enabling parameter, if so, the request is directly admitted; otherwise, the processing of the third method is continued.

Therefore, the four call admission control methods provided by the invention can improve the admission control efficiency and effectively utilize system resources; in addition, the third and fourth methods of the invention can also flexibly configure the uplink/downlink access control on the whole, thereby ensuring the system stability and the resource utilization rate.

Drawings

FIG. 1 is a flowchart illustrating a preferred embodiment of downlink admission control according to a first method of the present invention;

FIG. 2 is a flowchart illustrating a preferred embodiment of uplink admission control according to a second method of the present invention;

fig. 3 is a process flow diagram of a third call admission control method according to a preferred embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

The first call admission control method provided by the invention mainly comprises the following steps:

RNC receives the call request to obtain the existing service information of the current access cell;

b. judging whether the request reason of the current call is channel reconfiguration, if so, executing the step c;

c. d, judging whether the current request access service requires to improve the QoS of the downlink, if so, executing the step d; otherwise, the call request is accepted, and the current processing is finished;

d, RNC judges whether the down link can be accessed to the current call according to the call request, the existing service information of the down link of the current access cell and the preset load threshold of the down link of the cell, if so, the call request is accepted; otherwise, the call request is rejected.

The system sets a load threshold for each cell in advance, and the RNC receives a call request, acquires the existing service information of the uplink and the downlink of the current access cell and then enters an admission control process. The method of the present invention can be applied to admission control of downlink, and the first method of the present invention is described in detail below with reference to fig. 1. As shown in fig. 1, the specific processing steps include:

step 101: and the RNC inquires the service information in the call request and the acquired existing service information of the current access cell to obtain the QoS of the requested access service, the reason of the call request, the load measurement value of the cell downlink and the existing service.

Here, the call request includes service information, which in turn includes: the QoS of the requested access service, the reason of the call request and the like, wherein the QoS also comprises the following steps: information such as service type, request rate, minimum/maximum service rate, etc., wherein the service type includes: voice traffic, data traffic, and so on; the existing service information of the cell comprises: the base station measurement value of the current cell load level, the existing service composition and other information.

The existing service information of the cell comprises cell load measurement values of an uplink and a downlink, existing service composition and the like; for asymmetric traffic, the QoS is different between uplink and downlink, and therefore, when performing uplink admission control, the QoS used is uplink QoS, whereas when performing downlink admission control, the QoS used is downlink QoS.

Step 102: judging whether the call request reason of the current call is channel reconfiguration according to the call request reason in the step 101, if so, executing a step 103; otherwise step 104 is performed.

Step 103: judging whether the downlink QoS of the request channel reconfiguration service is required to be increased according to the QoS in the service information obtained by inquiring in the step 101, if so, executing a step 107; otherwise step 104 is performed.

For the channel reconfiguration of the existing traffic, if the QoS is not required to be increased, the load level of the cell is not increased after the channel reconfiguration, so that step 107 can be executed to directly admit the call request if the QoS in the channel reconfiguration request is not required to be increased.

The invention divides the reason of the call request into: switching, channel reconfiguration and new service access, but do not exclude the possibility of performing different divisions on the call request reason in the future network planning stage, and the method and the number of the division of the call request reason are not limited in the present invention.

Step 104: the RNC estimates the load level of the downlink of the entire cell after accessing the call according to the QoS of the downlink of the requested access service, the load measurement value of the downlink of the cell, and the existing service configuration described in step 101. Here, the reason for the request for accessing the service is that: handover, new service access, or channel reconfiguration with increased QoS requirements; when estimating the cell load level, the parameters such as the request rate and the service type in the QoS of the requested access service can be used for calculation.

The method of the present invention may use the measured value of the base station of the total uplink interference or total downlink transmission power of the cell as the cell load, or may use the load factor of the service throughput rate or the device demodulation capability as the definition of the load, but is not limited to the above definition, and also includes the load definition that may be used for the correlation analysis and newly appeared in the future technology development; when estimating the load level of a cell after new service access, if a service request is generated by increasing the speed of a certain link from low due to a correlation algorithm, subtracting the existing load of the link from the load of the current cell, and estimating the load level of the whole cell after the service access according to the request speed of the service and the like.

In addition, the estimation method of the cell load, the load measurement index used and the specific scheme of converting the load measurement value into the load index are not limited to one, different load estimation methods, load measurement indexes and schemes of converting the load measurement value into the load index can be adopted according to actual needs, and the load estimation method, the load measurement index and the scheme of converting the load measurement value into the load index are not the key points of the invention, so that the detailed description is not given here.

Step 105: judging whether the current cell downlink can not access the call request, namely judging: whether the estimated cell downlink load level exceeds a preset downlink load threshold in step 104, if yes, executing step 106; otherwise step 107 is performed.

The system available bandwidth is that under the limitation of the cell load threshold, the maximum rate that the service can use is calculated by using the current load level measurement result, the service type in the requested access service QoS and other parameters. Therefore, it is also possible to determine whether the current call can be accessed by estimating the available bandwidth of the system after accessing the call request, and the above steps 104 and 105 become:

step 104: RNC calculates the available bandwidth of the current downlink system according to the measurement result of the current downlink load level, the service type in the QoS of the request access service and other parameters; step 105: judging whether the estimated system available bandwidth in the step 104 is smaller than the request rate in the request access service QoS, if so, turning to a step 106; otherwise, go to step 107; here, the specific method for estimating the available bandwidth of the system is not important in the present invention, and thus will not be described in detail.

Step 106: the call request is rejected and the current process ends.

Step 107: the call request is accepted, and the current process is ended.

In the above processing procedure, the RNC may process different call request reasons. For the call request generated by channel reconfiguration, according to whether the call request requires increasing QoS, deciding whether the load level after admission needs to be estimated or not, and making a decision according to the load threshold, and directly admitting the call request which does not require channel reconfiguration with increased QoS, thereby reducing the processing burden of admission control.

In addition, considering different requirements and service quality expectations of operators and users for calls of different request reasons and service types, the invention can also adopt the load threshold of a service priority mechanism to carry out admission control, divide the call request into a plurality of priorities according to different request reasons and service types, and adopt different load thresholds to carry out judgment according to the priorities. Generally, a call drop caused by handover between cells or sectors during a call is the most unacceptable service failure for a user, and a smooth access to a voice service call is also highly desirable for the user, but the immediate access requirements of the user to other services such as data services are relatively low. Therefore, the priority of the call request generated by the handover is the highest, which is the first guarantee access of the system, the priority of the voice service is slightly lower, and the priority of other services such as data service is the lowest.

The invention sets different load thresholds for the call requests of different request reasons and service types to ensure the priority access of the high-priority service. The method of the invention divides the call request of the service into three priority levels from high to low: the request reasons are switched service, service with voice service type and other services, and the load threshold is set to be three types from high to low: a handover traffic load threshold, a voice traffic load threshold, and other traffic load thresholds. Such as: assuming that the maximum critical value of the total downlink transmission power of the cell ensuring the stability of the system is 95%, the handover traffic load threshold may be 80%, the voice traffic load threshold may be 70%, and the other traffic load thresholds are 60%. Here, since the demands and expectations of users for services are changed at different stages of network planning, the present invention does not limit how to prioritize call requests and how to set the load thresholds of services with respective priorities, but does not affect the effectiveness of the present invention.

Based on the above call admission policy of the load threshold using the service priority mechanism, step 105 further includes: judging the request reason and the service type of the current call request, and if the request reason is switching, adopting a switching load threshold; if the service type is voice service, adopting a voice service load threshold; if the service is other than the switching service and the voice service, other service load thresholds are adopted. Therefore, the RNC can adopt different load thresholds to carry out comparison judgment with the estimated cell load level according to the request reason and the service type of the call request. It can be known from the above-mentioned method for configuring the priority of the load threshold that the call request of the handover service is most likely to be accessed, and then the voice service and finally other services are performed, so that the quality of the handover service and the voice service is preferentially ensured, and more resources are reserved for the handover service and the voice service.

The method of the invention can be applied to the admission control of the dedicated channel. Since the service carried on the common channel has strong randomness and discontinuity, and it is difficult to accurately estimate the system load generated by the service, the admission control is usually not performed on the common channel, but the common channel load is directly assumed as a constant theoretically to simplify the analysis of other problems. However, the assumed constant value is large, and in an actual system, such assumption is too conservative for the sufficient utilization of system resources, and when performing admission control on a dedicated channel, the system resources occupied by a common channel need to be considered.

The method of the invention reserves certain resources for the public channel in a flexible mode when the access control of the special channel is carried out, and can improve the utilization rate of system resources. The resource reservation method specifically comprises the following steps: the method comprises the steps of using a common channel load configuration parameter in advance, monitoring the use condition of a common channel, obtaining an adjustment parameter through simulation or an external field test, and determining a common channel load reserved value according to the adjustment parameter. Such as: in the downlink, when the carrier emission power is used as the load water balance value, the power configuration parameter of the downlink common channel can be used to monitor the power use condition of the downlink common channel, then the adjustment parameter is obtained through simulation or external field test, and then the power reserve value of the downlink common channel is determined according to the adjustment parameter.

Therefore, step 104' is further performed before the above step 105: obtaining a downlink load threshold considering the common channel load reservation value; then a decision is made in step 105 using the downlink load threshold obtained in step 104'. Wherein, the difference between the downlink load threshold and the common channel load reservation value is the downlink load threshold considering common channel resource reservation. By adopting the flexible public channel resource reservation mode, the utilization efficiency of system resources can be considered, the admission control algorithm considering the public channel is simplified, and the stability of the system is ensured.

The above is the admission control scheme of the first method applied to the downlink, and the second method provided by the present invention is mainly applied to the admission control of the uplink. Fig. 2 is a flowchart illustrating a preferred embodiment of uplink admission control according to a second method of the present invention. Steps 201 to 207 and step 204 'shown in fig. 2 are substantially the same as steps 101 to 107 and step 104' shown in fig. 1, except that:

the cell load measurement value is a load measurement value of an uplink, the QoS of the requested access service is the QoS of the uplink, the estimated cell load level after the access call request is the cell load level of the uplink, the load threshold is an uplink load threshold, and the common channel load reserved value is a common channel load reserved value of the uplink.

In addition, the step 202 is: judging the reason of the call request according to the received call request, and if the reason is channel reconfiguration, executing step 203; if the same frequency switching is performed, step 207 is executed; if the reason is inter-frequency handover or other reasons, step 204 is executed. This is because, in the uplink, the load is generated by the transmitting power of the handset, if the current call is the same frequency switching service, the load generated by the access service is already included in the uplink base station cell load measurement value, so that the uplink is directly admitted for the same frequency switching service. Based on the special processing of the uplink to the same-frequency switching service, when the load threshold of the service priority mechanism is adopted, the switching service load threshold is exactly the load threshold of the different-frequency switching service.

In the above processing described in fig. 1 and fig. 2, when the load threshold of the admission control is used to decide whether the current call can be accessed, a one-time comparison method is used. However, in the WCDMA system, services can be classified into two types, real-time and non-real-time services, according to the QoS of the services; the traffic can also be classified into controllable and uncontrollable traffic according to controllability of the load caused by the traffic. Controllable services refer to those services that are not sensitive to delay, i.e. non-real-time services, such as: packet services and adaptive multi-rate (AMR) voice services, etc.; uncontrollable traffic refers to those traffic that are delay sensitive, have rate or minimum rate limitations, i.e. real-time traffic, such as: AMR voice services at minimum rates, etc. The load generated by the controllable service is a controllable load, and the load generated by the uncontrollable service is an uncontrollable load, so that the cell load is composed of the controllable load and the uncontrollable load. Therefore, both the existing service of the system and the service requesting access may be controllable services, and the generated load may also be controllable load. Thus, for these controllable services, the system can not only perform admission control in a one-time comparison manner, but also perform admission control on the call request in a manner of adjusting the rate of the controllable services, i.e., performing service negotiation, thereby maximizing the system capacity and making full use of the wireless resources.

Therefore, when it is determined in step 105 or step 205 that the current call cannot be accessed, a negotiation mechanism may be further employed, and whether the call request can be accessed after the controllable service in the existing service and the service requiring admission is adjusted is determined according to the conditions of the existing service and the service requiring admission, so that system resources can be fully utilized to access more calls. The admission control method of the negotiation mechanism is described in detail in another patent application of the present inventor and will not be further described here.

Since in the actual admission control process, it is often necessary to perform admission control on both the uplink and the downlink, then the method of the present invention may first perform the admission control on the downlink as shown in fig. 1, and further perform the admission control on the uplink as shown in fig. 2 on the current call request when deciding to accept the current call; or, firstly, performing the uplink admission control described in fig. 2, and further performing the downlink admission control described in fig. 1 on the current call request when deciding to accept the current call; and then accepts the call request admitted for both uplink and downlink.

The third call admission control method is characterized in that the RNC sets admission control enabling parameters for each cell, and the processing steps include: RNC receives the call request and obtains the existing service information of the current access cell; judging whether the cell requires uplink admission control according to the admission control enabling parameter of the cell, and if so, performing the uplink admission control; otherwise, the call request is accepted, and the current processing is finished; or, judging whether the cell requires the downlink access control, if so, performing the downlink access control; otherwise, the call request is accepted, and the current processing is finished.

Wherein the judging is that: when determining whether to perform uplink admission control, before accepting the call request, the method may further include: judging whether the cell requires to carry out admission control of a downlink, if so, carrying out admission control processing of the downlink; otherwise, the call request is accepted. The judgment is as follows: when determining whether to perform downlink admission control, before accepting the call request, the method may further include: judging whether the cell requires the admission control of the uplink, if so, performing the admission control processing of the uplink; otherwise, the call request is accepted.

Fig. 3 is a schematic processing flow chart of a third call admission control method according to a preferred embodiment of the present invention, as shown in fig. 3, the processing steps are as follows:

step 301: RNC receives the call request, obtains the service information of the cell and reads the admission control enabling parameter of the current request access cell.

Step 302: judging whether the cell requires uplink admission control according to the admission control parameters, if so, executing step 303; otherwise, step 304 is performed.

Step 303: performing uplink admission control, and determining whether the uplink decides to accept the call request, if so, executing step 304; otherwise, go to step 307.

The processing of this step is the same as the processing of steps 201 to 205 shown in fig. 2, and will not be described in detail here. Obviously, in the uplink admission control as described in fig. 2, when deciding to accept the call request, the following steps are performed: when judging that the QoS of the channel reconfiguration request does not require to be increased, or judging that the QoS of the channel reconfiguration request is a request of same-frequency switching, or judging that the current call can be accessed, executing a step 304; and when it is determined that the current call cannot be accessed, step 307 is performed.

Step 304: judging whether the cell requires downlink admission control according to the admission control parameters, if so, executing step 305; otherwise, step 306 is performed.

Step 305: the downlink admission control is performed, and the processing of this step is the same as the processing of step 101 to step 105 shown in fig. 1, and is not described in detail here.

Similarly, in the downlink admission control shown in fig. 1, when deciding to accept the call request, the following steps are performed: when judging that the QoS of the channel reconfiguration request does not require to be increased or judging that the current call can be accessed, executing step 306; and when it is determined that the current call cannot be accessed, step 307 is performed.

Step 306: the call request is accepted, and the current process is ended.

Step 307: the call request is rejected and the current process ends.

The process described in fig. 3 is performed with uplink admission control first, but the method of the present invention does not limit the order of uplink and downlink admission control, and may also determine whether downlink admission control is required in step 302, perform the process for downlink admission control in step 303, determine whether uplink admission control is required in step 304, and perform the process for uplink admission control in step 305.

As can be seen from the processing described in fig. 3, the method of the present invention can flexibly configure the uplink/downlink admission control of each cell for different network planning conditions of each cell, thereby ensuring the stability of the system and reducing unnecessary admission control processing. Such as: for some cells, the current situation of network construction requires that the cells must carry out uplink and downlink admission control, and the admission control enabling parameter of the cell can be set to indicate that the cells require to carry out uplink and downlink admission control simultaneously; when some cells are in a certain network planning stage, it can be predicted that the uplink or downlink load level of the cells does not exceed the load threshold, and the cells do not need to be subjected to uplink and/or downlink admission control, and the admission control enabling parameter of the cell can be set to indicate that only uplink or downlink admission control is required or no admission control is required; or, according to the implementation situation of the RNC, the uplink or downlink admission control algorithm may be in an unstable state, and in order to ensure the stability of admission control within a period of time, the uplink or downlink admission control function with an unstable algorithm needs to be closed, and the uplink or downlink admission control function can be closed by setting the admission control enabling parameter.

However, for those cells which do not need admission control, it is not necessary to make two judgments to decide whether to perform admission control, that is, to judge: whether to perform uplink admission control and whether to perform downlink admission control. In order to perfect the configuration of the third method for the admission control of each cell, the present invention can also judge whether the cell refuses to perform the admission control according to the admission control enabling parameter of the current access cell after the RNC receives the call request, if so, the call request is accepted, and the current processing is finished; otherwise, judging whether the cell requires uplink admission control according to the admission control enabling parameter of the cell, and if so, performing the uplink admission control; otherwise, the call request is accepted, and the current processing is finished; or, judging whether the cell requires the downlink access control, if so, performing the downlink access control; otherwise, the call request is accepted, and the current processing is finished. Therefore, step 301' may be further performed before step 301 described above: judging whether the cell refuses to carry out admission control according to the admission control enabling parameter of the current access cell, if so, executing step 306; otherwise, step 301 is performed.

It can be seen that the method of the present invention not only can manage the uplink/downlink admission control of each cell as a whole, but also considers the request reason, service type and other factors of the call request, and improves the specific uplink/downlink admission control as the first method, thereby improving the admission control efficiency, preferentially ensuring the access of the service with higher service quality requirement, and effectively utilizing the wireless resources of the system.

In summary, the call admission control method disclosed in the present invention can perform effective admission control for different request reasons and service types of a call request, and can perform preferential admission for services with high requirements on service quality according to expectations of users and operators for services, and can perform admission control by effectively utilizing system resources, and also manage admission control as a whole, thereby ensuring stability of the system.

Claims

1. A call admission control method, characterized by the processing steps comprising:

a. a base station controller RNC receives a call request and acquires the existing service information of a current request access cell;

b. c, judging whether the recording request reason of the current call is channel reconfiguration or not, if so, executing the step c; otherwise, executing step d;

c. d, judging whether the current request access service requires to improve the service performance of the downlink and requires QoS, if yes, executing step d; otherwise, the call request is accepted, and the current processing is finished;

2. The method of claim 1, wherein the accepting of the call request in step c or step d further comprises:

3. The method of claim 1 or 2, wherein the cell downlink load threshold comprises: a switching service load threshold and a non-switching service load threshold;

4. The method of claim 3, wherein the handover traffic load threshold is higher than a non-handover traffic load threshold.

5. The method of claim 1 or 2, wherein the cell downlink load threshold comprises: a switching service load threshold, a voice service load threshold and a non-switching and voice service load threshold;

before the determining whether the downlink can access the current call, the method further comprises: judging the request reason and the service type of the current call according to the call request, and if the current call is a switching service, adopting a switching service load threshold; if the voice service is the voice service, adopting a voice service load threshold; if the traffic is other than the switching traffic and the voice traffic, the non-switching and voice traffic load thresholds are adopted.

6. The method of claim 5, wherein the voice traffic load threshold is above a non-handover and voice traffic load threshold and below a handover traffic load threshold.

7. The method according to claim 1 or 2, characterized in that a common channel load reservation value is set in advance for each cell;

before the determining whether the downlink can access the current call, the method further comprises: and taking the difference between the downlink load threshold and the public channel load reserved value of the current cell as the load threshold value for carrying out admission control judgment on the cell.

8. A call admission control method, characterized by the processing steps comprising:

9. The method of claim 8, wherein the accepting the call request in step b1, step c1, or step d1 further comprises:

the RNC judges whether the downlink can be accessed to the current call or not according to the call request, the existing service information of the downlink of the current request access cell and the preset load threshold of the downlink of the cell, and if so, the call request is accepted; otherwise, rejecting the call request and ending the current process.

10. The method of claim 9, wherein the cell downlink load threshold comprises: a switching service load threshold and a non-switching service load threshold;

11. The method of claim 10, wherein the handover traffic load threshold is higher than a non-handover traffic load threshold.

12. The method of claim 9, wherein the cell downlink load threshold comprises: a switching service load threshold, a voice service load threshold and a non-switching and voice service load threshold;

13. The method of claim 12, wherein the voice traffic load threshold is above a non-handover and voice traffic load threshold and below a handover traffic load threshold.

14. The method of claim 9, wherein a common channel load reservation value is set for each cell in advance;

15. A call admission control method is characterized in that an RNC sets admission control enabling parameters for each cell, and the processing steps comprise:

d2, RNC judges whether the up link can be accessed to the current call according to the call focal point, the existing service information of the up link of the current request access cell and the preset load threshold of the up link of the cell, if yes, the call request is accepted, and the current processing is finished; otherwise, rejecting the call request and ending the current processing;

g2.RNC judges whether the down link can be accessed to the current call according to the call request, the existing service information of the current request access cell down link and the preset load threshold of the cell down link, if so, the call focal point is accepted; otherwise, the call request is rejected.

16. The method according to claim 15, wherein in step a2, it is determined whether to perform uplink admission control; before the determining that the cell does not require uplink admission control and receives the call request, the method further includes:

d21.RNC judges whether the down link can be accessed to the current call according to the call focal point, the existing service information of the current request access cell down link and the load threshold of the cell down link, if yes, the call request is accepted; otherwise, rejecting the call request and ending the current process.

17. The method according to claim 15, wherein in step a2, determining whether to perform downlink admission control; before the determining that the cell does not require downlink admission control and receives the call request, the method further includes:

f21. judging the focal point reason of the current call, if the focal point reason is the same frequency switching, receiving the call request; if it is a channel reconfiguration, performing step g 21; if the reason is other than the same-frequency switching and channel reconfiguration, executing step h 21;

18. A method according to any one of claims 15 to 17, characterized by setting a common channel load reservation for each cell;

before the determining whether the downlink can access the current call, the method further comprises: and taking the difference between the downlink load threshold and the public channel load reserved value of the current cell as the load threshold value of the cell admission control judgment.

19. A call admission control method is characterized in that an RNC sets admission control enabling parameters for each cell, and the processing steps comprise:

c3. judging the request reason of the current call, if the call is the same frequency switching, receiving the call request, and ending the current processing; if it is a channel reconfiguration, performing step d 3; if the medical treatment is other than the same-frequency switching and channel reconfiguration, executing step e 3;

20. The method according to claim 19, wherein in step b3, it is determined whether to perform uplink admission control; before the determining that the cell does not require uplink admission control and receives the call request, the method further includes:

22. A method according to any of claims 19 to 21, characterized by setting a common channel load reservation for each cell;