Implementation method for controlling power in external ring

Abstract

The method carries out an adjustment for target Eb / Io within one or multiple transmission block cycle, including following steps: making statistics for actual value of BLER; comparing actual BLER with target BLER; it is not changed if both is identical; if BLER is larger than target BLER, then one step length stepup is increased; if BLER is smaller than target BLER, then one step length stepdown is decreased; finally, based on compared result, changing controlled target Eb / Io for external ring. Advantages are: synthesized consideration between data service and voice service, variable step length adopted for power control on external ring, satisfied quality requirement of error block rate of chain even mobile wireless transmission environment changed a lot.

Description

technical field [0001] The invention relates to a code division multiple access (CDMA) system, in particular to a power control method in the CDMA system. Background technique [0002] Power control technology is the core technology of code division multiple access system. The code division multiple access system is a self-disturbing system. All mobile users on the same frequency occupy the same bandwidth. Since different users have different distances from the base station, the power of the user signal when it reaches the base station is also different; The power is high, and the receiving power of the remote users at the base station is small, causing mutual interference. This phenomenon is called the near-far effect. The traditional narrowband code division multiple access system requires that the average power of the signals arriving at the base station receiver of all users must be equal in order to despread normally. Power control is to overcome the "near-far effect...

AI Technical Summary

Problems solved by technology

[0012] The above method has great disadvantages and is not suitable for the outer loop power control of the third generation mobile communication system

The reason is as follows: if the same fixed step size is used for different services, it will cause a waste of resources, which will cause extremely serious consequences for the third-generation mobile communication system with limited resources.

For example: if the step size adopted is too small, the control precision will be high, but the response speed cannot keep up with the signal change, which will cause continuous error frames and cause a large call drop rate; if the step size adopted is too large Larger, the response speed is faster, but the control accuracy is difficult to guarantee, which will cause a waste of inner ring transmission power and greatly affect the capacity

Especially for data services with high rate and high transmission power, it will cause serious consequences to the entire system

Therefore, an inappropriate step size will greatly affect the stability and capacity of the system.

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