Downlink power control method and device thereof

Abstract

The invention relates to a method controlling a downlink power and a device thereof, wherein the method includes the following steps: the downlink TPC error-receiving rate PTPC_BER_Est is measured in real-time and is estimated according to the uplink dedicated channel pilot error-receiving rate PBER_Cur; the current downlink TPC PTPC(k) is maintained if the current downlink TPC error-receiving rate PTPC_BER_Est is lower than or equal to the default threshold PTPC_BER_Target, otherwise, the current downlink TPC TPTC(k) is set to zero to perform real-time inner ring power control. The device comprises an estimation module for the downlink TPC error-receiving rate and a regulation module for the downlink power which are sequentially connected with each other. The method and the device determine the quality of the uplink signal through measuring the pilot error-receiving rate, then evaluates the reliability of the downlink TPC power control command received by the network side as a foundation to the downlink power control, thereby avoiding the overdeviation of the downlink power caused by the poor quality of the uplink signal.

Description

technical field [0001] The present invention relates to mobile communication, in particular to a downlink power control method and its device, and mainly relates to the downlink power control method and its device in a WCDMA system. Background technique [0002] With the rapid development of the third-generation mobile communication technology, the application of mobile data and multimedia communication will become more and more extensive. The traditional second-generation Global System for mobile Communication, referred to as GSM communication network, has been unable to adapt to the new development trend. For this reason, GSM will gradually transition to the third generation mobile communication system. Among them, the 3rdGeneration Partnership Project, referred to as 3GPP, is a standardized wideband code division multiple access Wideband Code Division Multiple Access, referred to as WCDMA, with its continuous improvement and mature technical standards, flexible network ar...

AI Technical Summary

Problems solved by technology

[0008] Regarding the idea of ​​inner-loop power control, Qualcomm has described it in detail in the US patent document "Method and apparatus for adjusting a signal-to-interference threshold in a closed loop power control communications system". The author of the patent is Stein A. Lundby, and The Publication number is US Patent 6529482. In addition, the specific process of the inner loop power control is also described in detail in the 3GPP25.214 protocol. The problem with this inner loop power control method is that when the uplink quality is relatively poor, the uplink When the downlink TPC power control information carried in the network is unreliable received by the network side, the downlink transmission power offset phenomenon will occur

[0011] (1) The UE suddenly enters a shadow area, or the UE uplink suddenly suffers a short-term strong interference, the UE's uplink power has not had time to catch up quickly, and the UE's uplink quality deteriorates, which will inevitably lead to accurate reception of downlink TPC power control commands by the network side performance decline, high bit errors, and downlink TPC misjudgment, which in turn caused the downlink power adjustment to deviate from the expected adjustment direction

[0012] (2) When the UE is in the handover area, the quality of the uplink signal will be too poor when the soft handover is performed, the network side will receive the downlink TPC bit error, and the downlink transmit power will be inaccurate

Although RL1 may require the UE to increase the uplink power due to the deterioration of the quality of the uplink and downlink, but at this time the uplink and downlink path loss between the UE and cell 2 is decreasing, and the quality of the uplink and downlink is gradually improving, and cell2 on the network side may maintain the The uplink of the UE is well received, and the uplink TPC power control command is sent to the UE at the same time, requiring the UE to gradually reduce the uplink transmission power, so the UE must maintain a low uplink power, cell 2 can receive correctly, and cell 1 due to the increase in path loss The reception quality cannot be guaranteed. As a result, cell 1 on the network side decodes the downlink TPC power control command incorrectly, causing the downlink power of cell 1 to be too high, causing additional interference to other UEs, and affecting system capacity and system performance.

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