MIMO-based downlink data transmission method, device and system

Abstract

The invention discloses a multiple input multiple output (MIMO)-based downlink data transmission method, device and system. The method comprises the following steps of: receiving an uplink signal transmitted by a user terminal, executing uplink channel estimation based on the uplink signal to acquire corresponding uplink channel state information and converting the uplink channel state information into corresponding downlink channel state information; and calculating a pre-coding matrix aiming at the user terminal according to the acquired downlink channel state information, pre-coding downlink transmission data according to the acquired pre-coding matrix and transmitting the pre-coded downlink transmission data to the user terminal. Thus, the accuracy for acquiring the pre-coding matrix can be improved, the acquired downlink channel state information can be matched with the adopted pre-coding matrix, and optimal pre-coding is realized, so that the pre-coding gain is improved, and the system capacity is greatly improved.

Description

technical field [0001] The present invention relates to the communication field, in particular to a MIMO-based downlink data transmission method, device and system. Background technique [0002] In a Long Term Evolution (LTE) system, the network side usually uses Multiple Input Multiple Output (MIMO) technology to transmit and receive signals through multiple antennas at the transmitter and receiver, thereby greatly improving System transmission performance and capacity. Among them, MIMO-based transmit diversity technology is to repeatedly send precoded data streams at the transmitter to obtain diversity gain and coding gain; while MIMO-based spatial multiplexing technology is to simultaneously transmit multiple different data streams at the transmitter , so that the capacity and spectrum efficiency of the communication system can be doubled without increasing the bandwidth, which truly embodies the essence of the capacity improvement of the MIMO system. However, the use of...

AI Technical Summary

Problems solved by technology

However, there are quantization errors in PMI-based precoding technology, which will lead to the loss of precoding gain; at the same time, the estimation of precoding matrix and CQI by the user terminal side has great restrictions on the base station side, because the base station cannot base on the actual network environment. Flexible selection of optimal precoding matrix and accurate CQI estimation

[0006] To sum up, the existing downlink data transmission method is not ideal for realizing the precoding matrix. Therefore, it is necessary to provide a new downlink data transmission method to overcome the above-mentioned defects.

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