A method for asynchronous interference suppression in a multi-base station cooperative communication system

Abstract

The embodiment of the invention discloses a multi-base station cooperative communication system asynchronous interference rejection method comprising the following steps: building a base station and user same codebook set; using the minimum mean squared error estimation method to estimate a channel matrix Hj corresponding to users j (j=1,..K); quantifying the user j channel matrix, and returning a quantified channel index value obtained by quantification to the base station; allowing the base station to restore the user j channel matrix from the cookbook according to the index value, and using a BD algorithm to calculate a user j precoding matrix according to the restored channel matrix; allowing the base station to transmit signals according to the obtained precoding matrix. The method uses the feedback bit number corresponding to the signal to noise ratio to solve the quantification codebook, uses the codebook to quantify the user channel state information, and uses the BD algorithm to resolve and obtain the precoding matrix according to the quantified channel state information for transmission, thus improving the precoding matrix algorithm, reducing the system rate loss, and well rejecting the asynchronous interferences.

Description

technical field [0001] The invention relates to the technical field of wireless communication, in particular to an asynchronous interference suppression method for a multi-base station cooperative communication system. Background technique [0002] Multi-base station cooperative communication technology, also known as coordinated multi-point transmission (Coordinated Multi-point, COMP) technology, can effectively improve the communication transmission rate of the entire cell, especially the transmission rate of cell edge users through the cooperation between different base stations, thereby been extensively and in-depth researched. However, since there is no radio network controller in the multi-base station cooperative system, the synchronization of transmitted signals between base stations cannot be realized through unified scheduling. In this way, the signals sent by the cooperative base station to the same user cannot be synchronized. Even if the useful signal received ...

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Problems solved by technology

However, since there is no radio network controller in the multi-base station cooperative system, the synchronization of transmitted signals between base stations cannot be achieved through unified scheduling

In this way, the signals sent by the cooperative base station to the same user cannot be synchronized. Even if the useful signal received by the user can be synchronized through the time advance technology, it is difficult to synchronize the interference signal because of the position difference between the base station and the user.

Therefore, the signal received by the user has inherent asynchronous characteristics, and the inter-cell interference caused by asynchrony is much more serious than that of the synchronous system.

[0003] As an implementation form of multi-base station cooperative communication, precoding technology can pre-suppress spatial interference signals, thereby reducing the complexity of signal detection at the receiving end and attracting attention. However, since the precoding matrix is ​​the channel state fed back by the base station through the user end The information is calculated, and the bandwidth of the feedback channel is limited, which may easily cause the base station to fail to obtain perfect channel state information in practical applications.

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