CN1163010C - A dynamic channel configuration method for code division multiple access cellular mobile communication system - Google Patents

Abstract

The present invention relates to a dynamic channel configuration method for a code division multiple access cellular mobile communication system. The method comprises the steps that measurement control parameters are configured for a grouping service; a measurement report is received, and a measurement result is extracted; whether the current load situation needs to be obtained is determined, and a channel reconfiguration decision is made according to the determination result; when event triggering or periodic reports are realized, and the triggering has the reason that the result of service measurement is larger than the upper threshold or smaller than the lower threshold, the parameters of the load situation are obtained, and the reconfiguration decision of dynamic channels is comprehensively made; or the reconfiguration decision of dynamic channels is made only through considering the result of service measurement; according to the determination result, suitable new channel resources are configured for the service.

Description

A dynamic channel configuration method for code division multiple access cellular mobile communication system

The invention relates to a code division multiple access (CDMA) cellular mobile communication system, in particular to a dynamic channel configuration method for the code division multiple access cellular mobile communication system.

With the development and rapid popularization of the Internet, more and more wireless devices (such as mobile phones) have provided Internet access functions to enjoy WWW (World Wide Web) browsing, FTP (file transfer) downloading and E_Mail (electronic mail) provided by the Internet. E-mail) and other packet services whose source data rate varies greatly. For example, when the user clicks on the WWW page connection, a download request will be sent. During this request, one or more packet sequences will be sent. At this time, there will be a large amount of data on the channel to request rapid transmission; After the document is downloaded, the user spends a certain amount of time reading it, so the amount of data on the channel becomes very small at this time. It can be seen from this that these packet services are characterized by burstiness and a large dynamic range of rate changes. If the channel resource of fixed bandwidth is allocated to this service according to the conventional method, it may not be able to meet the demand of fast data transmission when the service bursts, and the redundant channel resource will be wasted when there is little service data. An effective solution is to dynamically configure the channel according to the changing characteristics of the business. If the current data rate to be transmitted is so high that the originally allocated channel bandwidth cannot meet the requirements, the channel will be reconfigured and assigned to it. Larger channel resources; when relatively idle, reconfigure a small bandwidth to the service again, so as to improve the utilization efficiency of channel resources.

Figure 1 shows a typical feature of a packet service. It can be seen from the figure that the session process of a packet service is composed of several packet calls, and each packet call contains multiple packet requests. There is a certain arrival time interval between packets. When a packet call arrives, the user Use a period of time (reading time) to read the arriving data. During this period of time, there is very little data on the channel; when the data reading is completed, the packet call is initiated again; the cycle continues until the end of the service.

To improve resource utilization efficiency, it is necessary to dynamically configure appropriate channel resources for certain packet services, thereby reserving more resources for the system to provide more user access services. This means that for a certain variable-rate service, we need to track its changing data requirements in time to provide a reliable basis for dynamic channel configuration.

In the third generation mobile communication system (such as WCDMA cellular mobile communication system), dynamic channel configuration is realized through traffic measurement. During the data service communication period, the service volume of the service is continuously measured, and the relevant parameters of the measurement are configured by the high layer, including the measurement object, measurement quantity, trigger threshold and report mode, etc. When the reporting method is periodic, if the measured traffic reaches or exceeds the trigger threshold, a traffic measurement report will be initiated; when the reporting method is periodic, the measured traffic will be reported periodically at a certain time It is given to the upper layer to make a decision on dynamic channel configuration.

FIG. 2 shows a schematic diagram of an event-triggered traffic report. The traffic in the figure may be the amount of data to be transmitted in the buffer, and the trigger threshold is given by the high layer through measurement control. In Figure 2a, when the measured traffic volume exceeds the upper threshold, a traffic report that exceeds the upper threshold is triggered; similarly, in Figure 2b, when the measured traffic volume is lower than the lower threshold, a report that is lower than the lower threshold is triggered. Traffic report. The measured data volume of the buffer corresponding to the service (or also includes the mean value and variance of the data volume) will be given in the report.

After receiving the service volume report, the upper layer performs dynamic channel configuration according to the report volume in the report: if the measured service volume exceeds the upper threshold, the service (or user) is configured with a channel with a larger capacity than the current channel, To better meet the user's business needs; on the contrary, if the measured traffic is lower than the lower threshold, the business (or user) is configured with a channel with a smaller capacity than the currently used channel, and more channels are reserved for the system. Wireless resources, thereby improving the resource utilization efficiency of the system.

However, when the system load is saturated or close to saturation, if the service demand of a certain user suddenly increases, so that the measured service volume exceeds the set upper threshold and triggers a report, the upper layer will reconfigure the channel according to the above method , to allocate a larger channel capacity to the user to meet its ever-changing business needs. But the result is often not as imagined. When the system load is saturated, the mutual interference between users makes the user's receiving quality reach or approach the lowest point. If the user's channel capacity continues to be improved in this case, it will inevitably be further improved. Mutual interference between users, in order to maintain a certain signal-to-interference ratio of received signals, the channels related to other users will also increase the transmission power appropriately, which will most likely lead to a sharp decline in the performance of the entire system.

The purpose of the present invention is to provide a kind of dynamic channel configuration method for CDMA cellular mobile communication system, this method improves the utilization efficiency of system channel resource while satisfying user service quality requirement, avoids many unnecessary channel reconfiguration processes, reduces Signaling interaction improves system performance.

In order to achieve the above object, the present invention provides a dynamic channel configuration method for a code division multiple access cellular mobile communication system. Appropriate measurement control parameters mainly include the upper and lower thresholds for triggering the measurement report and the trigger mode of the measurement report; after receiving the measurement report, extract the parameters in the measurement report, mainly including the measurement result of the traffic volume and the trigger reason of the measurement report; judge whether it is necessary to obtain The current load status of the system, and the channel reconfiguration judgment is made according to the judgment result: 1) If the trigger mode of the measurement report is event trigger or periodic report, and the trigger reason is that the measurement result of the traffic exceeds the upper threshold, then the related system Load parameters; send a request to obtain the current load status of the system and obtain the load status parameters; combine the current load status parameters of the system and the traffic measurement results to comprehensively perform dynamic channel reconfiguration judgments: if the current load status parameters indicate that the current system load is relatively light , the judgment result is to configure channel resources with a larger capacity for the service; if the current load status parameters indicate that the system is currently under heavy load, the judgment result is not to perform dynamic channel configuration and maintain the currently used channel resources; if the current load status parameters Indicates that when the current system load is close to saturation, the decision result is to reduce the channel resources used by the service; 2) If the trigger mode of the measurement report is event trigger or periodic report, and the trigger reason is that the measurement result of the service volume is lower than the lower threshold, then no It is necessary to obtain the load parameters of the relevant system; only consider the traffic measurement results to make a dynamic channel reconfiguration decision, and the decision result is to reduce the channel resources used by the service; according to the decision result, allocate appropriate new channel resources for the service.

In the above-mentioned dynamic channel configuration method for the CDMA cellular mobile communication system, the method for obtaining the current load status parameter of the system can be: measure the downlink transmission power of the base station and obtain the ratio β to the maximum allowable transmission power and set two There are three thresholds L1 and L2, and 1>L1>L2>0; if β<L2, it indicates that the current load of the system is light; if L2<β<L1, it indicates that the current load of the system is heavy; if β>L1, then Indicates that the system load is close to saturation.

In the above-mentioned dynamic channel configuration method for the code division multiple access cellular mobile communication system, the method for obtaining the current load status parameter of the system may be: measure the current data throughput rate of the service and obtain the maximum allowable capacity allocated to the service The ratio of data transmission rate γ; set two thresholds P1 and P2, and, 1>P1>P2>0; if γ<P2, it indicates that the system load is close to saturation; if P2<γ<P1, it indicates that the system is currently loaded heavy; if γ>P1, it indicates that the current load of the system is relatively light.

The above-mentioned dynamic channel configuration method fully considers three situations of the load of the current system, namely: 1) for the situation that the load of the current system is relatively heavy, even if the traffic measurement result exceeds the upper threshold, it is necessary to consider maintaining the current channel resources, Without reconfiguration to increase channel capacity, many unnecessary channel reconfiguration processes are avoided, many unnecessary signaling interactions are reduced, and system performance is optimized; 2) For very heavy system loads, even if the traffic measurement If the result exceeds the upper threshold, it is also necessary to consider configuring fewer channel resources for the service, thereby avoiding the adverse situation of rapidly deteriorating system performance and improving the overall performance of the system; 3) For the case where the traffic measurement result is lower than the lower threshold , then the channel reconfiguration to reduce the channel capacity can be directly performed regardless of the system load condition. Therefore, the present invention can perform dynamic channel configuration according to the change of business requirements on the premise of satisfying user business service quality requirements, effectively improve the utilization rate of system resources and reduce unnecessary channel reconfiguration times.

Following result embodiment and accompanying drawing further illustrate the present invention.

Fig. 1 is a schematic diagram of a business model of a WWW browsing service;

FIG. 2 is a schematic diagram of an event-triggered traffic report;

Fig. 3 is a schematic flow chart of the present invention;

Fig. 4 is a schematic diagram of dynamic channel configuration decision combined with system load.

As shown in FIG. 4 , a schematic diagram of dynamic channel configuration decision. Among them: the curve represents the system load status at different times. R1, R2, R3, and R4 represent traffic measurement reports in four event-triggered modes, corresponding to time T1, T2, T3, and T4, and assume that measurement report R1 is triggered because the traffic volume is lower than the lower threshold of traffic measurement Yes, the measurement reports R2, R3 and R4 are triggered because the traffic exceeds the upper threshold of traffic measurement.

The parameter TH1 indicates that the system load is close to saturation, TH2 indicates that the system load is relatively heavy but not close to saturation, and TH3 indicates that the system load is relatively light.

When the measurement report R1 is received, because the report is triggered because the measurement result of the traffic volume is lower than the lower threshold of the traffic volume, a judgment can be made directly without considering the current load status of the system, and the judgment result is to increase the channel capacity channel reconfiguration.

When the measurement report R2 is received, because the measurement result of the traffic volume at this time is greater than the upper threshold of the traffic volume, and the current system load is less than TH2, that is to say, the system load is not heavy, so the judgment result is to perform channel reconfiguration to increase the channel capacity .

When the measurement report R3 is received, it means that the measurement result of the traffic volume at this time is greater than the upper threshold of the traffic volume, but because the system load is greater than TH1 at the same time, that is to say, the system load is close to saturation, so the decision result is to reduce the channel capacity of the channel Reconfiguration instead of increasing channel capacity. Such a judgment result can reduce the load of the system appropriately, avoiding the sharp deterioration caused by the continuous increase of the load of the system, and improving the overall performance of the system.

When the measurement report R4 is received, it means that the measurement result of the service volume is greater than the upper threshold of the service volume at this time, but because the system load is greater than TH2 at the same time, that is to say, the system load is already relatively heavy, so the judgment result is not to perform channel reconfiguration. The channel resources originally allocated to the packet service remain unchanged.

As shown in Figure 3, the following are the basic steps of the method:

1) After a user establishes a packet service, configure appropriate measurement control parameters according to the initially allocated channel resources, including measurement objects, upper and lower thresholds for triggering measurement reports, and measurement report triggering methods;

2) After receiving the measurement report, extract the parameters in the measurement report, including the measurement result of the traffic volume, the trigger reason of the measurement report, etc.;

3) Determine whether to obtain the current load status of the system: if the trigger mode of the measurement report is event trigger and the trigger reason is that the traffic exceeds the upper threshold, or the trigger mode of the measurement report is periodic report and the measurement result of the traffic exceeds the upper threshold, then To obtain relevant system load parameters, execute 4); otherwise, if the trigger mode of the measurement report is event trigger and the trigger reason is that the traffic volume is lower than the lower threshold, or the trigger mode of the measurement report is periodic trigger and the measurement result of the traffic volume is less than the lower threshold, then It is not necessary to obtain the load parameters of the relevant system, perform step 6);

4) Send a request to obtain the current load status of the system and obtain load status parameters;

Among them, there are many ways to obtain the current load status of the system. A relatively simple method is: measure the downlink transmit power of the base station and obtain the ratio β to the maximum allowable transmit power: set two thresholds L1 and L2, and, 1>L1>L2>0; if β<L2, it indicates The current load of the system is light; if L2<β<L1, it indicates that the current system load is heavy; if β>L1, it indicates that the system load is close to saturation.

Another method that is easier to implement is to measure the actual flow of a packet service, or throughput. Measure the current data throughput rate of the service and obtain the ratio γ to the maximum allowable data transmission rate assigned to the service; set two thresholds P1 and P2, straight, 1>P1>P2>0; if γ<P2, then It indicates that the system load is close to saturation; if P2<γ<P1, it indicates that the current system load is relatively heavy; if γ>P1, it indicates that the current system load is relatively light.

5) In combination with the current load status parameters of the system and the traffic measurement results, comprehensively carry out the reconfiguration judgment of the channel: if the current load status parameters indicate that the current load of the system is relatively light, the judgment result is to configure channel resources with a larger capacity for the business; if When the current load status parameter indicates that the current load of the system is relatively heavy, the decision result is not to perform dynamic channel configuration and maintain the currently used channel resources; Channel resources used by the service. Then perform step 7);

6) The dynamic channel configuration judgment that only considers the traffic measurement result: since the traffic measurement result is lower than the lower threshold at this time, the judgment result is to reduce the channel resources used by the business;

7) According to the judgment result, configure new appropriate channel resources for the service.

Claims (3)

1. dynamic channel configuration method that is used for code vision multiple address cellular mobile communication system, its step comprises:

After certain user had set up a Packet Service, the suitable measurement Control Parameter of channel resource configuration according to original allocation mainly comprised the last Lower Threshold and the measurement report triggering mode that trigger measurement report;

After receiving measurement report, extract the parameter in the measurement report, mainly comprise the measurement result of traffic carrying capacity, measurement report triggers reason;

Whether judgement needs the present load situation of the system that obtains, and carries out the judgement of reshuffling of channel according to this court verdict:

1) if the measurement report triggering mode is the report of Event triggered or cycle, and to trigger reason be that the measurement result of traffic carrying capacity surpasses Upper threshold, then will obtain relevant system load parameter;

Send the request that needs acquisition system present load situation and obtain the load state parameter;

Coupling system present load condition parameter and measuring business volume result, comprehensively carry out the judgement of reshuffling of dynamic channel:

If the present load condition parameter shows that court verdict was to be the more jumbo channel resource of this business configuration when system's present load was light;

If the present load condition parameter shows when system's present load is heavier that court verdict is kept the channel resource of current use for not carrying out the dynamic channel configuration;

If the present load condition parameter shows current system load when saturated, then court verdict is for reducing the channel resource that this business is used;

2) if the measurement report triggering mode is the report of Event triggered or cycle, and to trigger reason be that the measurement result of traffic carrying capacity is lower than Lower Threshold, then do not need to obtain the load parameter of relevant system;

Only consider that the measuring business volume result carries out dynamic channel and reshuffles judgement, and court verdict is to reduce the channel resource that this business is used;

According to court verdict, be the suitable new channel resource of this business configuration.

2. a kind of dynamic channel configuration method that is used for code vision multiple address cellular mobile communication system according to claim 1 is characterized in that, the method that obtains the present load condition parameter of system is:

Measure base station down transmitting power and acquisition and the maximum ratio beta that allows transmitting power;

Set two thresholding L1 and L2, and, 1＞L1＞L2＞0;

If β＜L2 shows that then system's present load is lighter;

If L2＜β＜L1 shows that then system's present load is heavier;

If β＞L1 shows that then system load is near saturated.

3. a kind of dynamic channel configuration method that is used for code vision multiple address cellular mobile communication system according to claim 1 is characterized in that, the method that obtains the present load condition parameter of system is:

Measure the current data throughput of this business and obtain and distribute to the reportedly ratio γ of defeated speed of this professional maximum allowable number;

Set two thresholding P1 and P2, and, 1＞P1＞P2＞0;

If γ＜P2 shows that then system load is near saturated;

If P2＜γ＜P1 shows that then system's present load is heavier;

If γ＞P1 shows that then system's present load is lighter.

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