Method for transmitting signals of multi-input multi-output system and codebook feedback method

Abstract

The invention provides a signal transmission method and a codebook feedback method in a multiple-input multiple-output (MIMO) system. The codebook feedback method comprises the following steps: after receiving a signal transmitted from a transmitting end, a receiving end calculates the current codebook matching with the current channel estimation result, and feeds the codebook information back to the transmitting end; wherein the codebook information is the difference of the serial number of the current codebook and the previous codebook. The signal transmission method comprises the following steps: after receiving a signal transmitted from a transmitting end, a receiving end feeds the difference of the serial number of the current codebook and the previous codebook back to the transmitting end; and the transmitting end obtains the serial number of the current codebook according to the serial number of previous codebook and the difference, weighs the signal according to the codebook corresponding to the serial number of the current codebook, and transmits to the receiving end. The technical proposal provided in the invention can remarkably reduce feedback cost of a system under the same codebook design accuracy, or design more codebooks under the same feedback cost of the system, thereby remarkably improving the channel feedback accuracy.

Description

technical field [0001] The invention relates to the field of mobile communication, in particular to a signal sending method and a codebook feedback method in a multiple-input multiple-output system. Background technique [0002] In the case of limited channel bandwidth, the system capacity of the system can be greatly improved by using MIMO (Multiple Input Multiple Output) technology. Precoding (precoding) technology is the channel information fed back by the sender through the receiver. The encoding matrix is ​​processed so that each data stream is equivalent to independent channels for transmission during the spatial channel transmission process. However, if the real channel characteristics are fed back, the required system overhead is very large. Therefore, in the current design, channel feedback is usually performed through codebook feedback. In the current codebook feedback method, the most similar codebook is found according to the current channel characteristics, and...

AI Technical Summary

Problems solved by technology

If more codebooks need to be designed for more accurate feedback channel characteristics, then the feedback overhead will increase with the number of codebooks

And if in order to reduce the codebook overhead, it is necessary to design fewer codebooks or reduce the feedback frequency, then the codebook accuracy or channel feedback accuracy will be reduced accordingly

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