Method for reducing peak-to-average power ratio of frequency domain forming OFDM (Orthogonal Frequency Division Multiplexing) without bandwidth expansion

Abstract

The invention discloses a method for reducing a peak-to-average power ratio of frequency domain forming OFDM (Orthogonal Frequency Division Multiplexing) without bandwidth expansion and mainly solves the problem that the peak-to-mean ratio performance of an OFDM signal showed in the prior art is too low. The method disclosed by the invention comprises the following steps of: (1) carrying out a serial-to-parallel conversion on input signals by a signal processor and obtaining signal sequences in parallel transmission; (2) multiplying a diagonal matrix and a square matrix, made up of different Chu sequences, to acquire a pre-coding matrix, and weighing the signal sequences by using the pre-coding matrix; (3) constructing a Gaussian-like function as a frequency domain forming function, and weighing the signals; (4) after carrying out a zero insertion operation and a rapid inverse Fourier transform on each data symbol, performing a parallel-to-serial conversion on the signal sequences andacquiring OFDM transmission signals suitable for transmission. The method for reducing the peak-to-average power ratio of frequency domain forming OFDM (Orthogonal Frequency Division Multiplexing) without bandwidth expansion, disclosed by the invention, has the advantages of low complexity and high utilization rate of frequency spectrum; and the peak-to-average ratio of the signals can be reducedremarkably without losing bit error rate of received signals, and the power utilization rate of a transmitter of a communication system is improved.

Description

technical field [0001] The present invention belongs to the technical field of communication, and further relates to a method for reducing signal peak-to-average power ratio (Peak to Average Power Ratio, PAPR, referred to as peak-to-average ratio) in an orthogonal frequency division multiplexing (orthogonal frequency division multiplexing, OFDM) system. To improve the transmission performance of OFDM system. Background technique [0002] Compared with traditional technology, OFDM transmission technology can provide larger coverage, better transmission quality, higher data rate and spectral efficiency. However, since the data symbols in the OFDM transmission system are superimposed by multiple independently modulated subcarrier signals, when the subcarrier phases of each data signal are the same or similar, the signals will be modulated by the same initial phase signal, thus Generate a larger instantaneous power peak, resulting in a higher peak-to-average ratio. Since the d...

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Problems solved by technology

[0004] The disadvantages of this method are: first, the computational complexity of this method is too high due to multiple fast Fourier transform and matrix multiplication operations on the signal sequence; second, this method needs to transmit the sideband information of the signal , once the receiving end makes an error in receiving the sideband information, the bit error rate performance of the signal will drop sharply; Performance Value Requirements

[0006] The disadvantages of this method are: first, the reduction of the peak-to-average ratio is not large enough to meet the requirements of most mobile user terminal equipment on the performance value of the peak-to-average ratio; secondly, this method needs to occupy additional signals of the communication system Bandwidth and transmit power, reducing the spectrum utilization and power utilization of the communication system

[0008] The disadvantage of this method is that the reduction of the peak-to-average ratio is not large enough to meet the requirements of most mobile user terminal equipment for the performance value of the peak-to-average ratio

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