CN100428859C - Method and device for call admission control - Google Patents

Abstract

The invention discloses a call admission control method. After receiving an access request of a new service, the method includes: A. judging whether it is currently in a congested state, and if so, rejecting the current access request and ending the current processing Process; otherwise, execute step B; B. Estimate the estimated value of the channel quality indicator CQI report after accessing the new service, and judge whether the estimated value of the CQI report reaches the CQI threshold corresponding to the service, if yes, execute step C; otherwise refuse to accept The current access request ends the current processing flow; C. Estimates the power requirement estimate after accessing the new service, and judges whether the power requirement estimate exceeds the preset power threshold, and if so, refuses to accept the current access request; Otherwise, the current access request is accepted. The invention also discloses a device, which can implement admission control for services with high real-time performance and continuous high bit rate by applying the method and device of the invention.

Description

Method and device for call admission control

technical field

The present invention relates to the technical field of call admission control, in particular to a call admission control method and device applied to High Speed Downlink Packet Access (HSDPA).

Background technique

At present, HSDPA is an important feature of the 3GPP R5 version. It realizes downlink high-speed data transmission through a series of key technologies such as adaptive modulation and coding (AMC), hybrid retransmission (HARQ), and fast scheduling of base stations.

Since HSDPA has higher spectral efficiency than dedicated channels, the industry is considering mapping streaming services, which are expected to play an important role in the evolution of packet data services in 3G mobile networks, to HSDPA. At this time, when the HSDPA channel accepts an access request of a new streaming service, the service quality of the existing streaming service on the HSDPA channel should not be affected. Therefore, the radio network controller (RNC) of the wideband code division multiple access (WCDMA) system should adopt a call admission control mechanism to ensure the quality of streaming service on the HSDPA channel. Here, the services supported by the WCDMA system can be divided into four categories: conversational (Conversational) services, streaming (Streaming) services, background (Background) services, and interactive (Interactive) services. Sensitive business is also called Best Effort (BE, Best Effort) business.

However, the initial design of HSDPA is a channel for non-real-time services that are not sensitive to delay, while streaming services have high delay requirements and continuous high bit rates. Therefore, the existing call admission methods for HSDPA channels on the RNC do not consider the admission control of flow services such as those with strict delay requirements, and usually only consider some background services or interactive services that are not sensitive to delay, so only use Simple methods such as throughput threshold or user number threshold are used for admission control. These existing admission control methods are not applicable to streaming services. If admission control is to be performed on streaming services, it is necessary to conduct more adequate analysis of the usage of HSDPA channel resources and the possible impact of new streaming services. consider.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a call admission control method and device, which can realize call admission control for services requiring high real-time and continuous high bit rate.

In order to achieve the above object, technical solution of the present invention is achieved in that way:

The invention discloses a call admission control method. After receiving an access request of a new service, the method includes:

A. Judging whether it is currently in a congested state, if so, rejecting the current access request and ending the current processing flow; otherwise, perform step B;

B. Estimate the channel quality indication CQI report estimated value that obtains the current new service user, judge whether this CQI report estimated value reaches the CQI threshold of current new service, if yes, then perform step C; Otherwise refuse to accept current access request, end current processing flow;

C. Estimating the estimated value of the power requirement after accessing the new service, and judging whether the estimated value of the power requirement exceeds the preset power threshold, and if yes, rejecting the current access request; otherwise, accepting the current access request.

Wherein, the method for judging whether it is in a congested state in step A is: acquiring a congested state indication, and judging whether it is in a congested state according to whether the congested state indication is valid.

Wherein, the method for estimating and obtaining the estimated value of the CQI report in step B is: obtaining the pilot strength report of the current new service user, and then estimating and obtaining the estimated CQI report value of the new service user according to the pilot strength report.

In step B, the method of obtaining the estimated value of the CQI report of the new service user according to the pilot strength report is: obtaining the pilot strength from the pilot strength report, and obtaining the current new service user's CQI report value according to the pilot strength. Signal-to-interference ratio SIR estimated value; determine each CQI value that can guarantee a certain block error rate BLER and whose corresponding SIR value does not exceed the estimated SIR value, and use the maximum CQI value among the determined CQI values as the new service The estimated value of the user's CQI report.

In step B, the method for obtaining the CQI threshold of the current new service is: calculate according to the guaranteed bit rate GBR requirements of the current new service and the capability parameters of the new service user, and retrieve the CQI value mapping table of the current new service user according to the calculation result The TBS value set of the transport block size in the new service is obtained to obtain the minimum TBS value required by the new service, and then the CQI value corresponding to the minimum TBS value is obtained by mapping the CQI value mapping table of the new service user and used as the CQI threshold of the current new service .

In step B, the method for obtaining the minimum TBS value required by the new service is:

表示采用CQI值映射表中的离散数据进行向上取整处理。Among them, CQI _{th, i} is the CQI threshold of the current new service, For the minimum TBS value required by the new service corresponding to CQI _{th, i} , GBR _i is the GBR requirement of the current new service, i is the number of the current new service, Min Inter-TTI Interval is the capability parameter of the new service user, the new The capability parameter of a service user represents the minimum transmission time interval TTI that the new service user can support, and margin is a preset margin,

Indicates that the discrete data in the CQI value mapping table is used for upward rounding processing.

Wherein, the method for estimating and obtaining the estimated value of the power requirement in step C is: calculating the number of transmission time interval TTIs required by the current new service per second, and calculating the power value required by the new service according to the number of TTIs required by the new service per second , the power value required by the new service is added to the sum of the power of the existing service to obtain an estimated power requirement after accessing the new service.

In step C, the method for calculating the number of TTIs required by the current new service per second is: mapping the CQI value mapping table of the new service user to obtain the TBS value corresponding to the estimated value of the CQI report, and obtaining the TBS value of the current new service GBR requirement; calculate the TTI number required by the current new service per second according to the TBS value and the GBR requirement.

Wherein, before said refusing to accept the current access request, it further includes: transferring the current access request of the new service to the call admission control flow of the dedicated channel DCH, and rejecting the access to the call admission control flow of the DCH. When receiving an incoming request, refuse to accept the current access request.

The invention also discloses a call admission control device, which includes:

The congestion admission module receives the access request of the new service and the congestion status indication from the outside, and transfers the access request of the new service to the CQI admission module when it is judged that it is not in the congestion state;

The CQI admission module is configured to receive an access request of a new service from the congestion admission module, estimate the estimated value of the CQI report of the current new service user, and send the estimated value of the CQI report when it is determined that the estimated value of the CQI report reaches the CQI threshold of the new service The access request of the new service is transferred to the power admission module;

A power admission module, configured to receive an access request for a new service from the CQI admission module, estimate an estimated power requirement, and output to the outside to accept the new service when it is determined that the estimated power requirement does not exceed a preset power threshold Admission indication for an access request.

Wherein, the CQI admission module includes:

The SIR estimation module is used to receive the access request of the new service from the congestion admission module, obtain the SIR estimation value of the current new service user and output it to the CQI estimation module;

The CQI estimation module is used to receive the SIR estimation value from the SIR estimation module and determine the CQI report estimation value of the current new service user and output it to the CQI decision module;

A CQI judgment module, configured to receive the estimated value of the CQI report from the CQI estimation module, obtain the CQI threshold of the current new service, and when it is determined that the estimated value of the CQI report reaches the CQI threshold of the new service, receive the new service The admission request is forwarded to the power admission module.

Wherein, the power admission module includes:

A TTI calculation module, configured to receive an access request for a new service from the CQI admission module, calculate the number of TTIs required by the current new service and output it to the power calculation module;

A power calculation module, configured to receive the TTI number from the TTI calculation module and calculate

The power requirement value of the current new service, obtain the power of the current existing service, and calculate the access current new service

The estimated value of the power requirement after the service is output to the power decision module;

A power decision module, configured to receive the estimated power requirement from the power calculation module, save the power threshold, and output the admission indication to the outside when it is determined that the estimated power requirement does not exceed the preset power threshold.

Wherein, the device is an independently set entity, or integrated in the RNC of the WCDMA system; the new service is a Streaming service.

From the above solution, it can be seen that the key of the present invention is to sequentially perform congestion state judgment, CQI admission judgment and power admission judgment on the access request of the new service. Therefore, the call admission control method and device provided by the present invention can firstly avoid accessing new services when the system is busy or resources are insufficient, and then reject new services with poor user channel quality through CQI admission judgment, and In the final power admission decision, a more accurate estimation of system power resources can be made to ensure the quality of existing services and new services. The mechanism of the invention comprehensively considers the characteristics of high real-time and continuous high bit rate services such as stream services to perform admission control, effectively solving the problems existing in the access technology of such services on the current HSDPA channel.

Description of drawings

Fig. 1 is a schematic diagram of the processing flow of a preferred embodiment of the method of the present invention;

Fig. 2 is a schematic diagram of the relationship between power values in the power admission decision of the method of the present invention;

Fig. 3 is a schematic diagram of the composition and structure of a preferred embodiment of the device of the present invention.

Detailed ways

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

The present invention provides a call admission control method, the main design idea of which is: after receiving an access request for a new service, first enter the congestion state judgment process, and enter the CQI admission judgment process when it is judged that there is no congestion; then, Enter the power admission decision process when it is judged that the estimated value of the CQI report can reach the CQI threshold required by the current new service; finally, accept the current access request when the estimated value of the judged power requirement does not exceed the preset power threshold.

Wherein, the present invention is applied in access network (RAN, Radio Access Network) equipment, is usually applied in the radio network controller (RNC) of wideband code division multiple access (WCDMA) system, and can be specifically called by the call in RNC The admission control module realizes the present invention. The scope of application of the present invention is not limited to RNC, and various devices that are used to access stream services and need to perform admission control on stream services can apply the present invention. This article will take the call admission control module in RNC as an example to describe the present invention method is explained.

Fig. 1 is a schematic diagram of the processing flow of a preferred embodiment of the method of the present invention. As shown in Figure 1, after the call admission control module in the RNC receives the access request of the new streaming service, it performs the following processing steps:

Step 101: Judging whether the streaming service on the current HSDPA channel is in a congested state, if yes, go to step 109; otherwise go to step 102.

Here, the congestion control module for processing the HSDPA flow service in the RNC can send the congestion status indication of the stream service on the HSDPA channel to the call admission control module in the RNC, and the call admission control module can indicate whether the congestion status indication is valid according to the received To determine whether it is in a congested state. The processing of how the congestion control module performs congestion control and obtains a congestion status indication belongs to the category of congestion control mechanisms. Various congestion control technologies already exist in the industry, and are not the focus of the present invention. Therefore, this article will not further describe this.

Step 102: Obtain the pilot strength report of the current new streaming service user. Here, the specific method for obtaining the pilot strength report belongs to the scope of the prior art, which is not limited in the present invention.

Step 103: Obtain an estimated value of the channel quality indicator (CQI) report of the new streaming service user according to the pilot strength report obtained in step 102. Herein, the service user can be understood as a user equipment (UE) used by the service user.

Step 104: According to the estimated CQI report value obtained in step 103, judge whether the estimated CQI report value reaches the CQI threshold of the new stream service, if yes, execute step 105; otherwise, execute step 109.

Wherein, the acquired pilot strength report of the new streaming service user may be used to estimate the estimated value of the CQI report of the new streaming service user by the method described below, the method including:

1. Estimate the Signal-to-Interference Ratio (SIR) of the High Speed Downlink Physical Data Shared Channel (HS-PDSCH).

On the one hand, the SIR on the HS-PDSCH channel of UE _j can be expressed as formula (1)

${\mathrm{<span\; class="notranslate">\; SIR</span>}}_{\mathrm{<span\; class="notranslate">\; HS</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; PDSCH</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; CPICH</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; \&Gamma;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; tot</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; \&NotEqual;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\underset{<span\; class="notranslate">\; \&ForAll;</span>\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; tot</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Among them, SIR _{HS-PDSCH, j} is the SIR on the HS-PDSCH channel of UE _j , P _CPICH is the common pilot channel (CPICH) power, Γ is the measurement power offset (MPO), that is, the total power of the HS-PDSCH channel is relative to The offset of the CPICH channel power, Γ is the difference between the total power of the HS-PDSCH channel and the power of the pilot channel, rather than the parameters of the actual system configuration; N ₀ is the background noise; j is the number of the UE, and i is the number of the base station of the cell to which the UE belongs ; α _{i, j} is the orthogonalization factor, |h _{i, j} | ² is fast fading, α _{i, j} and |h _{i, j} | ² are used to carry the link of HS-PDSCH; P _{tot, i} is the cell The total transmit power of i, P _tot,n is the total transmit power of cell n; G _i,j is the path gain between UE _j and cell i, G _n,j is the path gain between UE _j and cell n.

On the other hand, the pilot strength CPICH_Ec/No can be expressed as the following formula (2):

$\mathrm{<span\; class="notranslate">\; CPICH</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; Ec</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; CPICH</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; tot</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; \&NotEqual;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\underset{<span\; class="notranslate">\; \&ForAll;</span>\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; tot</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

Therefore, it can be considered that the estimated value of SIR _{HS-PDSCH, j} is shown in formula (3):

SIR _{HS-PDSCH, j} ≈ CPICH_Ec/No·Γ (3)

Here, by comparing the SIR _{HS-PDSCH, j of the formula (1) and the formula (3),} it can be seen that the estimated value of the SIR _{HS-PDSCH, j} of the formula (3) is slightly smaller than the SIR _HS-PDSCH of the formula (1), j is true value; in addition, the RNC can obtain the CPICH_Ec/No from the acquired pilot strength report.

2. According to the estimated value of SIR _{HS-PDSCH, j} , RNC can check whether the estimated value of SIR _{HS-PDSCH, j} is good enough to ensure a certain preset block error rate (BLER), so as to obtain the estimated value of CQI report, the CQI The reported estimated value can be expressed as Equation (4) below.

$\mathrm{<span\; class="notranslate">\; CQI</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>\underset{<span\; class="notranslate">\; \&ForAll;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; max</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; SIR</span>}}_{\mathrm{<span\; class="notranslate">\; BLER</span>}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; 10</span>}<span\; class="notranslate">\; \%</span><span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&le;</span>{\mathrm{<span\; class="notranslate">\; SIR</span>}}_{\mathrm{<span\; class="notranslate">\; HS</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; PDSCH</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

Wherein, i represents the CQI value, SIR _{HS-PDSCH, and j} is the SIR value estimated by UE _j for the HS-PDSCH channel. Formula (4) sets the BLER to be guaranteed to be 10%, so SIR _{BLER≤10%, and j} is the SIR value corresponding to the HS-PDSCH channel when the BLER is less than or equal to 10%. The so-called CQI report estimated value is a channel quality indication given by the UE after estimating the channel quality. The mapping relationship table between SIR, BLER and CQI values can be pre-configured. The mapping table can be obtained through simulation, so it can be obtained The estimated value of the SIR and the maximum CQI value required by the preset 10% BLER, that is, the maximum CQI value among the CQI values that satisfy the conditions of SIR _{BLER ≤ 10%, i} ≤ SIR _{HS-PDSCH, j} , and determine the maximum CQI value The value is the estimated value of the current CQI report. Here, the CQI value that satisfies the conditions of SIR _{BLER≤10%, i} ≤SIR _{HS-PDSCH, j} is: the corresponding SIR does not exceed SIR _{HS-PDSCH, j} , and the CQI value that guarantees BLER within 10%; The known SIR estimated value SIR _{HS-PDSCH, j} is slightly smaller than the real value of SIR, so each SIR value meeting the condition of SIR _{BLER≤10%, i} ≤ SIR _{HS-PDSCH, j} must be less than the real value of SIR of the current new service user , so that the formula (4) can obtain a relatively accurate CQI estimation value.

3. Judging whether the estimated CQI report value reaches the CQI threshold of the current new streaming service according to the estimated value of the CQI report obtained above. If not, the new service should not be connected to the HSDPA channel.

Here, the estimated value of the Guaranteed Bit Rate (GBR) requirement carried in the Iu message of the current new streaming service and the capability parameters of the current new streaming service user can be used for calculation, and the current new streaming service user can be retrieved based on the calculation result The set of transport block size (TBS) values in the CQI value mapping table can obtain the minimum transport block size (TBS) value required by the current new streaming service, and the corresponding CQI value of the minimum TBS value in the CQI value mapping table is CQI threshold of the current new flow service. For example: the CQI threshold can be obtained according to the following formula (5). According to the WCDMA standard, a CQI value mapping table will be predefined for each type of UE. The mapping table includes: a set of CQI values and a set of transport block size (TBS) values, and each CQI value in the set of CQI values corresponds to Modulation mode, TBS value, coding rate value etc.; Described Iu message refers to the message of Iu interface interaction between RNC and base station Node B, and the present invention does not limit to the message that Iu message specifically represents.

表示采用CQI值映射表中的离散数据进行向上取整处理；margin为预设的裕量，可通过外场测试或仿真得到；由于一个TTI的时长为2毫秒，所以500为HS-PDSCH信道每秒钟所能提供的TTI的总数。Among them, CQI _{th, i} is the CQI threshold to be obtained, is the TBS value corresponding to CQI _th,i , which is the minimum TBS value required by the current new streaming service, and GBR _i is the GBR requirement carried in the Iu message of the current service, and the GBR requirement additionally considers the size estimation of the MAC-hs PDU header value, where i is the serial number of the current service; Min Inter-TTI Interval is a capability index parameter of the UE, and its meaning refers to the minimum transmission time interval (TTI) that the UE can support, that is to say: the UE needs at least "MinInter-TTI TTI Interval" so many TTIs to complete the necessary internal processing;

Indicates that the discrete data in the CQI value mapping table is used for upward rounding; margin is the preset margin, which can be obtained through field testing or simulation; since the duration of a TTI is 2 milliseconds, 500 is the HS-PDSCH channel per second The total number of TTIs that the clock can provide.

Step 105: According to the estimated CQI report value of the new streaming service user estimated in step 103, retrieve the TBS value corresponding to the estimated CQI report value in step 104 from the CQI value mapping table.

Step 106: According to the TBS value obtained in step 105 and the Guaranteed Bit Rate (GBR) requirement of the new streaming service, calculate the number of transmission time intervals (TTIs) required by the new streaming service per second.

Step 107: Calculate and obtain the power value required by the new streaming service according to the required TTI number per second obtained in step 106.

Step 108: According to the calculation in step 107, the power value required by the new streaming service and the power value of each service currently accessed are estimated to obtain the total power value after accessing the new streaming service, that is, accessing the new streaming service For the estimated value of the power requirement after the service, it is judged whether the estimated total power value exceeds the preset power threshold, if yes, go to step 110 ; otherwise, go to step 109 .

本实施例设定：UE₁......UE_n-1为RNC已接入的UE，而UE_n为当前请求接入的新的流业务的UE，则

可用来表示估计得到接入该新的流业务后的总功率值；所述预设的功率门限可记为P_SS，th，该P_SS，th应小等于P_HSPDSCH。可以按公式(6)所示的条件来进行步骤108所述判断：Here, the total power of the HS-PDSCH channel is constant, and the constant total power of the HS-PDSCH channel is recorded as P _HSPDSCH ; the power of UE _i is recorded as PS _S,i , then UE ₁ ... UE _n The sum of the power of n UEs is denoted as

This embodiment assumes that: UE ₁ ...UE _n-1 are UEs that have been accessed by the RNC, and UE _n is a UE currently requesting access to a new stream service, then

It can be used to indicate the estimated total power value after accessing the new streaming service; the preset power threshold can be recorded as P _SS,th , and the P _SS,th should be less than or equal to P _HSPDSCH . The judgment described in step 108 can be carried out according to the conditions shown in formula (6):

$\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; SS</span>}<span\; class="notranslate">\; ,</span><span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&le;</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; SS</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; th</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$

与时间相关。随着时间的推移，RNC接入的UE的数目、以及各个UE要求的功率都会发生变化，因此，该

的取值将随时间变化而变化，当该的值小等于P_SS，th时，当前新的流业务是可以接入的；但是当该

的值大于P_SS，th时，当前新的流业务不应被接入。从图2中可见，该预设的P_SS，th一定小于等于HS-PDSCH信道恒定的总功率P_HSPDSCH，该P_HSPDSCH可被看为呼叫准入控制意义上的HSDPA资源。In order to further understand the relationship between the various power values in the decision in step 108, these power values will be described below in conjunction with FIG. 2 . Fig. 2 is a schematic diagram of the relationship between power values in the power admission decision of the method of the present invention. As shown in Figure 2, the estimated total power value after accessing the current new stream service

related to time. As time goes by, the number of UEs accessed by the RNC and the power required by each UE will change. Therefore, the

The value of will change with time, when the When the value of is less than or equal to P _SS,th , the current new stream service can be accessed; but when the

When the value of is greater than P _SS,th , the current new stream service should not be accessed. It can be seen from FIG. 2 that the preset P _SS,th must be less than or equal to the constant total power P _HSPDSCH of the HS-PDSCH channel, and the P _HSPDSCH can be regarded as an HSDPA resource in the sense of call admission control.

Wherein, the method for estimating the power P _SS,n of the new service currently requesting access is as follows: since the total power of the HS-PDSCH channel is constant, the power per TTI is known. For each flow service on HSDPA, the number of TTIs required by the flow service per second can be obtained according to the GBR requirements considering the size of the MAC-hs PDU header and the TBS value, so that the flow service can be obtained according to the number of TTIs required per second The average power used per second may be used as an estimated power value of the UE. For example: if a stream service requires 5 TTIs per second to transmit data, the average power ratio of the stream service relative to the total power of the HS-PDSCH is 5/500, that is, 1/100. It should be noted that the so-called average power here refers to the actual bit rate of the air interface, not the GBR requirement carried in the Iu message. Therefore, by using the methods described in steps 102 to 104 to estimate the CQI report value, the estimated CQI report value of UE _n currently requesting to access the new streaming service can be obtained, and then the TBS value corresponding to the estimated CQI report value can be obtained. According to the obtained TBS value and the GBR requirement considering the MAC-hs PDU header size of the new streaming service currently requesting access, the number of TTIs per second required by UE _n currently requesting access to the new streaming service can be obtained. In this way, according to the number of TTIs required by the UE _n per second, the power requirement P _SS,n of the UE _n can be obtained.

In addition, according to the public measurement report from the base station Node B, the RNC can obtain the power P _SS,i (i=1,...,n-1) required by the UE that has access to each flow service that has a certain GBR requirement. Wherein, in the existing protocol, in order to perform call admission control and congestion control, the RNC requires the Node B to report the power requirement of each UE.

Since HSDPA is designed to be used for BE services, the setting of P _SS,th may depend on the coexistence policy of HSDPA upstream services and Best Effort (BE, Best Effort) services. However, the present invention does not limit the specific method for setting thresholds such as P _{SS, th} , etc. in the call admission control process of the present invention, and the strategy on which these thresholds are set.

Step 109: reject the access request of the new streaming service, and end the current processing flow.

Wherein, the refusal described in this step refers to refusing to access the new streaming service on the HSDPA channel. When rejecting the access request of the new streaming service, the call admission control process of the HSDPA channel involved in the present invention has just ended, and the RNC The access request of the new streaming service may be directly rejected, so that the access of the new streaming service fails.

In addition, the RNC can also transfer the access request of the new streaming service to the admission control procedure of the dedicated channel (DCH). In this way, if the new streaming service is allowed to access in the admission control process of the DCH, the RNC will access the new streaming service; if the new streaming service is rejected in the admission control process of the DCH access, the RNC rejects the new flow service, and thus the access fails. Here, the admission control mechanism on the DCH is not a problem involved in the present invention, so no further description will be given here.

Step 110: Accept the access request of the new streaming service.

Based on the above method of the present invention, the present invention also proposes a call admission control device, which includes three parts: a congestion admission module, a CQI admission module and a power admission module. The device may be integrated in the RNC, or may be an independently configured entity connected to the RNC.

Fig. 3 is a schematic diagram of the composition and structure of a preferred embodiment of the device of the present invention. As shown in FIG. 3 , the call admission control device is composed of three modules, including: a congestion admission module, a CQI admission module and a power admission module.

Among them, the congestion admission module is used to receive the access request of the new service from the outside, receive the congestion status indication from the congestion control module of the RNC, and transfer the access request of the new service to the CQI admission module when judging that it is not in the congestion state The CQI admission module is used to receive the access request of the new service from the congestion admission module, estimate the CQI report estimate value of the current new service user, and send the CQI report estimate value when it is determined that the CQI report estimate value does not exceed the preset CQI threshold The access request of the new service is forwarded to the power admission module; the power admission module is used to receive the access request of the new service from the CQI admission module, estimate the estimated value of the power requirement, and determine that the estimated value of the power requirement does not exceed When the preset power threshold is set, an admission indication indicating acceptance of the new service access request is output to the RNC.

The function of the above-mentioned device of the present invention can be realized according to the method of the flow chart shown in Figure 1, therefore, the CQI admission module can include: a SIR estimation module, a CQI estimation module and a CQI decision module, and the power admission module can include : TTI calculation module, power calculation module and power decision module.

In the CQI admission module, the SIR estimation module is used to receive the access request of the new service from the congestion admission module, obtain the SIR estimation value of the current new service user and output it to the CQI estimation module; the CQI estimation module is used to obtain the SIR estimation module from the SIR estimation module Receive the SIR estimate and determine the CQI report estimate of the current new service user and output it to the CQI decision module; the CQI decision module is used to receive the CQI report estimate from the CQI estimate module, obtain the CQI threshold of the current new service, and determine When the estimated value of the CQI report reaches the CQI threshold of the new service, the access request of the new service is transferred to the TTI calculation module in the power admission module. Here, the method for the SIR estimation module to estimate the SIR is as described in the previous formula (3), the method for the CQI estimation module to obtain the estimated value of the CQI report is as described in the previous formula (4), and the method for the CQI judgment module to obtain the CQI threshold is as described in the previous formula ( 5) and will not be described in detail here.

In the power admission module, the TTI calculation module is used to receive the access request of the new service from the CQI decision module in the CQI admission module, calculate the TTI number required by the current new service and output it to the power calculation module; power calculation The module is used to receive the TTI number from the TTI calculation module and calculate the power requirement value of the current new service, obtain the power of the current existing service, calculate the estimated value of the power requirement after accessing the current new service, and output it to the power judgment module The power judgment module is used to receive the estimated power requirement from the power calculation module, save the power threshold, and output an admission indication to the outside when it is determined that the estimated power requirement does not exceed the preset power threshold. Here, the TTI calculation module calculates the TTI number and the power calculation module calculates the power requirement value as described in step 105 to step 107 of the previous method embodiment, and will not be described in detail here.

It can be seen from the above-mentioned embodiments of the present invention that the processing of the present invention mainly includes: a congestion state determination process, a CQI admission determination process, and a power admission determination process. Through the congestion state judgment process, it is possible to avoid accessing new streaming services when the system is busy or insufficient in resources, because accessing new streaming services when existing services cannot be supported is neither reasonable nor can guarantee service quality, that is, service quality Latency and bit rate. In the CQI admission decision process, the streaming services of UEs with poor channel quality can be rejected, because if the streaming services of these UEs with poor channel quality are accessed, even if all system resources are allocated to the UE It also cannot meet its service quality requirements. The final power admission decision process is to make a more accurate estimate of the system resources (power) when the system is not congested, so as to ensure that the quality of each existing service and the new stream service requested for access is consistent after accessing the new streaming service. can be guaranteed. Therefore, the method of the present invention is particularly suitable for performing call admission control for services that require higher real-time and continuous high bit rates. At present, the present invention is mainly aimed at stream services, and the present invention can also be used for future possible Various services requiring high real-time and continuous high bit rate are used for call admission control.

Claims (13)

1. A call admission control method, characterized in that, after receiving an access request of a new service, the method comprises: A. Judging whether it is currently in a congested state, if so, rejecting the current access request and ending the current processing flow; otherwise, perform step B; B. Estimate the channel quality indication CQI report estimated value that obtains the current new service user, judge whether this CQI report estimated value reaches the CQI threshold of current new service, if yes, then perform step C; Otherwise refuse to accept current access request, end current processing flow; C. Estimating the estimated value of the power requirement after accessing the new service, and judging whether the estimated value of the power requirement exceeds the preset power threshold, and if yes, rejecting the current access request; otherwise, accepting the current access request. 2. The method according to claim 1, wherein the method for judging whether it is in a congested state in step A is: obtaining a congested state indication, and judging whether it is in a congested state according to whether the congested state indication is valid. 3. The method according to claim 1, characterized in that the method for obtaining the estimated value of the CQI report by estimating in step B is: obtaining the pilot strength report of the current new service user, and then estimating and obtaining the CQI report according to the pilot strength report. CQI report estimates for new service users. 4. The method according to claim 3, characterized in that in step B, the method for obtaining the CQI report estimated value of the new service user according to the pilot strength report estimation is: obtaining the pilot strength report from the pilot strength report Frequency strength, and according to the pilot strength to obtain the signal-to-interference ratio SIR estimated value of the current new service user; determine each CQI value that can guarantee a certain block error rate BLER, and its corresponding SIR value does not exceed the SIR estimated value, and The maximum CQI value among the determined CQI values is used as the CQI report estimated value of the new service user. 5. The method according to claim 1, wherein in step B, the method for obtaining the CQI threshold of the current new service is: according to the guaranteed bit rate GBR requirements of the current new service and the capability parameters of the new service user Calculate, retrieve the set of transport block size TBS values in the CQI value mapping table of the current new service user according to the calculation results, obtain the minimum TBS value required by the new service, and then obtain the minimum TBS value through the mapping table of the CQI value mapping table of the new service user. The CQI value corresponding to the TBS value is used as the CQI threshold of the current new service. 6. The method according to claim 5, characterized in that in step B, the method for obtaining the minimum TBS value required by the new service is:

Among them, CQI _{th, i} is the CQI threshold of the current new service,

For the minimum TBS value required by the new service corresponding to CQI _{th, i} , GBR _i is the GBR requirement of the current new service, i is the number of the current new service, Min Inter-TTI Interval is the capability parameter of the new service user, the new The capability parameter of a service user represents the minimum transmission time interval TTI that the new service user can support, and margin is a preset margin,

Indicates that the discrete data in the CQI value mapping table is used for upward rounding processing. 7. The method according to claim 1, wherein the method for estimating and obtaining the estimated value of the power requirement in step C is: calculating the number of transmission time interval TTIs required by the current new service per second, and according to the number of TTIs required by the new service per second The required TTI number is calculated to obtain the power value required by the new service, and the power value required by the new service is added to the sum of the power of the existing service to obtain an estimated power requirement after accessing the new service. 8. The method according to claim 7, characterized in that in step C, the method for obtaining the number of TTIs required by the current new service per second is: mapping the CQI value mapping table of the new service user to obtain the The CQI reports the TBS value corresponding to the estimated value, and obtains the GBR requirement of the current new service; calculates the number of TTIs required by the current new service per second according to the TBS value and the GBR requirement. 9. The method according to claim 1, further comprising: transferring the current new service access request to the call admission control process of the dedicated channel DCH before refusing to accept the current access request, and When the call admission control process of the DCH rejects the access request, it rejects the current access request. 10. A call admission control device, characterized in that the device comprises: The congestion admission module receives the access request of the new service and the congestion status indication from the outside, and transfers the access request of the new service to the CQI admission module when it is judged that it is not in the congestion state; The CQI admission module is configured to receive an access request of a new service from the congestion admission module, estimate the estimated value of the CQI report of the current new service user, and send the estimated value of the CQI report when it is determined that the estimated value of the CQI report reaches the CQI threshold of the new service The access request of the new service is transferred to the power admission module; A power admission module, configured to receive an access request for a new service from the CQI admission module, estimate an estimated power requirement, and output to the outside to accept the new service when it is determined that the estimated power requirement does not exceed a preset power threshold Admission indication for an access request. 11. The device according to claim 10, wherein the CQI admission module comprises: The SIR estimation module is used to receive the access request of the new service from the congestion admission module, obtain the SIR estimation value of the current new service user and output it to the CQI estimation module; The CQI estimation module is used to receive the SIR estimation value from the SIR estimation module and determine the CQI report estimation value of the current new service user and output it to the CQI decision module; A CQI judgment module, configured to receive the estimated value of the CQI report from the CQI estimation module, obtain the CQI threshold of the current new service, and when it is determined that the estimated value of the CQI report reaches the CQI threshold of the new service, receive the new service The admission request is forwarded to the power admission module. 12. The device according to claim 10, wherein the power admission module comprises: A TTI calculation module, configured to receive an access request for a new service from the CQI admission module, calculate the number of TTIs required by the current new service and output it to the power calculation module; A power calculation module, configured to receive the number of TTIs from the TTI calculation module and calculate the power requirement value of the current new service, obtain the power of the current existing service, calculate the estimated value of the power requirement after accessing the current new service, and output to the power decision module; A power decision module, configured to receive the estimated power requirement from the power calculation module, save the power threshold, and output the admission indication to the outside when it is determined that the estimated power requirement does not exceed the preset power threshold. 13. The device according to any one of claims 10 to 12, characterized in that the device is an independently configured entity, or integrated in the RNC of the WCDMA system; the new service is a Streaming service.

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