PTS method for lowering PAPR of MIMO-OFDM system

Abstract

The invention discloses a PTS method for lowering PAPR of an MIMO-OFDM system. Sub-block segmentation is carried out after information source bits are subjected to baseband modulation and series-parallel-connection conversion, time domain sub-block signals are obtained through IFFT modulation, all the time domain sub-block signals are subjected to time domain circulation shift of different lengths and then subjected to sub-block synthesis, and time alternative signals with different PAPRs are obtained. Meanwhile, after corresponding sub-blocks among antennas are switched, time domain circulation shift and sub-block synthesis are carried out to generate more time domain alternative signals, and then a sequence with the minimum PAPR is selected and emitted. Phase change is achieved through different lengths of circulation shift of the sub-blocks, more alternative sequences are obtained through sub-block switch among the antennas, more alternative sequence sets can be obtained under the condition of the same IFFT modulation amount, good PAPR inhibition performance is achieved, and blind detection of received signals is achieved by comparing the distance between a reverse rotary signal and a signal constellation point.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, in particular to a PTS method for reducing the PAPR of a MIMO-OFDM system. Background technique [0002] The multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system obtains diversity gain by using frequency, time and different antennas, which can effectively resist multipath and noise in wireless communication, and become the future mobile multimedia communication. One of the main candidate technologies. [0003] MIMO-OFDM signal is a kind of multi-carrier modulation signal, and one of the main disadvantages is that the signal peak power to average power ratio (PAPR) is relatively high. At present, a mainstream method to reduce MIMO-OFDM system is partial transmission sequence method (PTS method). Taking two transmitting antennas as an example, the basic principle of the traditional PTS method is: the OFDM signal of each antenna is divided int...

AI Technical Summary

Problems solved by technology

The disadvantages of the traditional PTS method are: 1. In order to obtain better PAPR suppression performance, each antenna needs to select a signal with the smallest PAPR from multiple candidate signals for transmission. When the number of phase factors P used by each sub-block is constant, To increase the number of candidate sequences can only increase the number of blocks, and each sub-block requires IFFT modulation, which increases the computational complexity of the algorithm; 2. In order for the system to restore the original signal at the receiving end, the transmitting end needs to transmit the phase factor. Sideband side information, the transmission of sideband side information reduces the spectrum utilization efficiency of the system, and the transmission error of the phase factor will lead to a significant increase in the bit error rate of the system

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