A method and device for updating the signal-to-noise ratio of TDS outer loop power control

Abstract

The present invention provides a method and device for updating the signal-to-noise ratio of TDS outer-loop power control. The method includes: obtaining the current block error rate Present_BLER, the current target signal-to-noise ratio Present_SNR_Target, the current upward adjustment step Present_UpStep, and the current downward adjustment Step size Present_DownStep; determine whether the Present_BLER is greater than the preset target block error rate BLER_Target; if so, then determine the target SNR target upstep step UpStep_Target of the target signal-to-noise ratio SNR_Target according to the Present_SNR_Target and Present_UpStep; if not, then according to the Present_SNR_Target and Present_DownStep determine the target downstep DownStep_Target of the target signal-to-noise ratio SNR_Target; update the SNR_Target according to the Present_SNR_Target, and UpStep_Target and / or DownStep_Target. The present invention is used to make the SNR_Target work in the linear region, avoiding too large or too small for a long time, so that the outer loop power control and the inner loop power control mechanism cooperate better, and reduce the fluctuation of the wireless link quality.

Description

technical field [0001] The present invention relates to the technical field of mobile communication, in particular to a method for updating the signal-to-noise ratio of TDS outer-loop power control, and a device for updating the signal-to-noise ratio of TDS outer-loop power control. Background technique [0002] In TDS (Time Division-Synchronous Code Division Multiple Access, Time Division Synchronous Code Division Multiple Access), RNC (Radio Network Controller, radio network controller) according to the BLER (Block Error Ratio, block error rate) statistics of the transmission channel As a result, adjust the increase / decrease of the target signal-to-noise ratio value SNR Target (Signal NoiseRatio, signal-to-noise ratio). If the adjustment step is fixed, it is easy to cause the phenomenon of SNR Target overadjustment, so that SNR_Target works in a relatively high area for a long time. . [0003] Closed-loop power control is an important way of power control in TDS. Closed-l...

AI Technical Summary

Problems solved by technology

In the existing outer loop power control process, the signal-to-noise ratio adjustment step (including up-step and down-step) is a fixed value. This design has the advantage of easy implementation, but in the real transmission environment In BLER and SNR_Target is not a simple linear relationship, but changes with changes in the environment, so there may be the following problems: If the step size is too large, it may cause the power control range to exceed the required range. If the uplink power of a user is increased too high, so that the BLER far exceeds the required target value, it will cause interference to other users. When it is lowered, the power of the user cannot meet the normal communication needs; If the value is too small, the power adjustment may not be able to keep up with changes in the environment, especially when the transmission environment changes rapidly, it will cause repeated power adjustments, increase the power control frequency of RNC, and reduce the frequency stability of TDS at the same time

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