Mobile terminal and downward power control method

Abstract

The invention provides a mobile terminal and downward power control method, comprising: measuring the signal-to-interference ratio of each coded composite transport channel to obtain respective signal-to-interference ratio measured value; calculating the signal-to-interference ratio predicted value of each coded composite transport channel according to the signal-to-interference ratio measured value; calculating the difference value between the maximum and the minimum in the signal-to-interference ratio predicted value; judging whether the difference value is larger than the preset first threshold, if yes, generating a power control command word which can decrease the transmitting power for the coded composite transport channel corresponding to the maximum and generating a power control command word which can increase the transmitting power for the coded composite transport channel corresponding to the minimum, if no, comparing the signal-to-interference ratio predicted values of the coded composite transport channels with respective signal-to-interference ratio target values thereof to generate respective power control command word. The invention can effectively improve the reliability and stability of a plurality of closed loop power control of the coded composite transport channels at the same time slot.

Description

Technical field [0001] The present invention relates to the field of mobile communication, in particular to a mobile terminal and a downlink power control method. Background technique [0002] In a mobile communication system, strong near-ground signals suppress weak far-ground signals to produce a "near-far effect". The channel capacity of the system is mainly limited by the co-channel interference of other systems or the interference of other users in the system. Therefore, the transmission power of the base station must be changed in real time to ensure the communication quality. This process is the downlink power control of the transmission power of the communication system. Through the downlink power control, the channel capacity can be improved. [0003] Such as figure 1 As shown, in the downlink control of the base station transmit power, a closed-loop power control mode can be used. In this control mode, the power control is divided into inner-loop power control and oute...

AI Technical Summary

Problems solved by technology

However, closed-loop power control has the characteristic that the control effect on the transmission power in a certain direction (uplink or downlink) depends on the link quality in another direction (downlink or uplink). When the multiple CCTrCHs exist in the same When there are multiple CCTrCHs in a certain direction (downlink or uplink), it is possible that the adjustment direction of the transmission power of each CCTrCH is opposite according to the different requirements of the mobile terminal for service Qos, or the transmission power of a certain CCTrCH The speed of power adjustment is accelerated, which will cause the signal reception quality of other CCTrCHs to deteriorate and cannot be recovered through closed-loop power control, resulting in call drop

[0005] Especially in the HSDPA (High Speed ​​Downlink Packet Access) process, due to the discontinuity of the SCCH (Shared Control Channel), the base station may perform an open-loop power control on the SCCH at regular intervals. The influence of the power control of the channel) will lead to the deterioration of the downlink signal quality of DPCH

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