Method for reducing peak to average power ratio of OFDM signal

Abstract

The invention provides a method for reducing a peak to average power ratio (PAPR) of an orthogonal frequency division multiplexing (OFDM) signal. In the method, the PAPR is reduced by a cascade selected mapping (SLM) method or a partial transmit sequence (PTS) method and an amplitude limiting method. The SLM or PTS with a small packet number is used for primarily reducing the PAPR of the signal, and a chipping ratio of time domain data which is output by the PTS or the SLM is set by the amplitude limiting method so as to reduce the PAPR to a target value. Compared with the method only using the PTS or SLM method, the method has the advantages that the implementation complexity is low due to the small used packet number. Compared with the amplitude limiting method, the method has the advantage that the PAPR of the signal is primarily reduced before the amplitude is limited so signal distortion is few at the same chipping ratio. The method integrates the advantage of few signal distortion of the PTS or SLM method, and the advantage of the amplitude limiting method that the PAPR is direct and the method is easy to implement. Under the gauss channel, the performance of the bit error rate is reduced to certain extent compared with that of original data, but the performance loss is not large in the range of the signal to noise ratio which is concerned by the design.

Description

technical field [0001] The invention relates to the field of wireless communication, in particular to the peak-to-average ratio reduction technology in the OFDM system. It can be used in the design of peak-to-average ratio reduction in OFDM. This method combines the advantages of small linear distortion of PTS and SLM methods in the peak-to-average ratio reduction method and the advantages of simple implementation and direct peak-to-average ratio reduction of the limiting method. Under the premise of high rate performance, the peak-to-average ratio reduction capability is improved and the complexity of implementation is reduced. Background technique [0002] With the increasing demand for mobile communications and wireless networks, more advanced wireless transmission technologies are increasingly required. One of the most immediate challenges in the design of high-speed wireless communication systems is to overcome the severe frequency-selective fading brought about by wir...

AI Technical Summary

Problems solved by technology

[0005] In theory, the scrambling code method is the most promising solution to the peak-to-average ratio problem in OFDM, but this method is more complicated, and the inverse operation of PAPR is required to restore the original data at the receiving end, which also increases the cost of the receiver

From a practical point of view, the pre-distortion method is simple and the most practical. More importantly, if the receiver is cost-effective if the direct limiting method is used, it will cause certain interference and system performance loss.

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