Beam forming method of time frequency domain joint treatment in TD-LTE (Time Division-Long Term Evolution) system

Abstract

The invention discloses a beam forming method of time frequency domain joint treatment in a TD-LTE (Time Division-Long Term Evolution) system, which comprises the following steps of: firstly, obtaining accurate information of an estimation channel by using an uplink pilot frequency insertion scheme, carrying out time prediction on the information of the estimation frequency domain channel so as to be used for compensating change of the channel, caused by system processing delay or mobile station movement, and specifically adopting linear prediction; secondly, carrying out frequency domain smoothing on the channel information obtained through prediction so as to be used for avoiding hop of estimation channels of adjacent subcarriers on magnitude and phase and reducing influence of noise and interference on a wave beam; and finally, carrying out calculation of a downlink wave beam forming weighting matrix on the smoothed channel information for realizing improvement on system performances.

Description

technical field [0001] The invention relates to a downlink beam forming method used in a TD-LTE (time-division duplex mode of long-term evolution protocol) system in which multiple antennas are configured at a base station and a single antenna is configured at a user end. It is mainly used for the inaccurate channel estimation of continuous pilots due to factors such as noise and interference. At the same time, the delay caused by uplink and downlink feedback and data processing, or the user's mobile speed is too fast, resulting in channel estimation that cannot reflect the downlink channel in real time. Therefore, if it is not suitable for calculating the weight vector of the beamforming, the accuracy of the beamforming is improved through the time-frequency domain joint processing of the channel, thereby improving the performance of the system. Background technique [0002] The beamforming method is mainly used in the preprocessing of information in wireless communication,...

AI Technical Summary

Problems solved by technology

[0007] For the TD-LTE system, due to the time difference between uplink and downlink transmission, the channel information during uplink and downlink transmission is not exactly the same. At this time, using the channel information estimated at the current moment to determine the beamforming weighting matrix for the next transmission will result in The defect of error caused by the change of channel, the present invention provides a prediction scheme in time; in addition, the channel on each subcarrier can be directly estimated by using the block pilot insertion method in the uplink, although the channel estimated in this way The information is very accurate on each subcarrier, but due to the existence of noise and interference, the slow variation between the originally associated subcarriers becomes weaker, making the channel information between adjacent subcarriers relatively independent and continuous. The lack of the channel estimated by the block pilot is precisely the slow-varying characteristic of the spatial channel. Therefore, the present invention proposes to smooth the estimated channel in the frequency domain after predicting in time, thereby improving the performance of the system.

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