WCDMA downlink channel parameter estimation method

Abstract

The invention relates to a downlink channel parameter estimation method in mobile communication, in particular to a method for accurately estimating the downlink channel parameters in a high-speed mobile environment. The WCDMA downlink channel parameter estimation method estimates the channel parameters in the high-speed mobile environment more accurately without reducing the communication efficiency, occupies less channel resources, and comprises the steps: putting a plurality of specific pilot symbols in a channel time slot on a public pilot channel of a sending end to enable two adjacent specific pilot symbols to be separated by N pilot symbols; calculating channel parameters of the specific pilot symbol time according to the specific pilot symbols on a public pilot channel of a receiving end, and then estimating channel parameters of other pilot symbols time between the two specific pilot symbols according to the calculated channel parameters of the time of the two adjacent specific pilot symbols, wherein N is a natural number larger than 1 and is selected according to the downlink channel conditions to meet requirements of the estimation accuracy of the downlink channel parameters.

Description

technical field [0001] The invention relates to a method for estimating downlink channel parameters in mobile communication, in particular to a method for accurately estimating downlink channel parameters in a high-speed mobile environment. Background technique [0002] HSDPA is an enhanced scheme proposed by 3GPP Release 5, which is applicable to both WCDMA and TD-SCDMA systems. Since 2005, HSDPA has become the most frequent occurrence in the global communication industry and the focus of attention of people from all walks of life in the communication industry. Viewed from the bottom layer, HSDPA mainly introduces Adaptive Modulation Coding (ACM) and Hybrid Automatic Repeat (H-ARQ) technology to increase data throughput. But both AMC and H-ARQ are based on the estimation of channel quality. Channel quality is reflected by channel parameters. The so-called channel parameters refer to the time response or frequency response of the wireless channel from the transmitting ante...

AI Technical Summary

Problems solved by technology

The common pilot channel is a downlink channel of the WCDMA system. The frame structure of the common pilot channel is as follows: figure 2 As shown in , the common pilot signal on it has the functions of auxiliary channel estimation, frame synchronization and as the default phase reference of other downlink channels, and the continuous pilot symbols used for channel estimation need to use all the pilots in the common pilot channel Symbol resources ("Optimum Channel Estimation Method under Continuous Pilot Mode in DS-CDMA System", Yang Xin, You Xiaohu, Electronic Journal, October 2004), this method will obviously lead to shortage of common pilot channel resources

Moreover, sending continuous pilot symbols takes up bandwidth and causes power redundancy. On the one hand, increasing the transmission power of the common pilot channel can improve the accuracy of parameter estimation, but it increases redundancy at the same time, and the high-power pilot channel It will constitute strong multiple access interference to the data channel; on the other hand, if the power of the common pilot channel is reduced, the channel parameter estimation will be inaccurate

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