Method and apparatus for reducing PAR

Abstract

The invention provides a method for reducing the peak-to-average power ratio, which comprises distributing the code-modulated signals on a plurality of sub-carrier waves, and combining the sub carrier waves into a plurality of physical resource blocks; combining the physical resource blocks into a plurality of subsequences; searching the optimal phase after respectively subjecting each of the subsequences to the rapid Fourier reverse transformation; and carrying out the phase rotation according to the optimal phase corresponding to each of the subsequences. With the method and the device, the signals of the multicarrier are divided into the subsequences and then the phase rotation is carried out based on the PRB; and since the data and the pilot-frequency information is in the same PRB, a transmitting terminal can accurately demodulate without need of a transmission side band information receiving terminal while carrying out the phase rotation to the subsequences, and the BER deterioration is also prevented.

Description

technical field [0001] The invention relates to the technical field of mobile communication, in particular to a method and device for reducing peak-to-average ratio. Background technique [0002] OFDM (Orthogonal Frequency Division Multiplexing, Orthogonal Frequency Division Multiplexing) multi-carrier system uses orthogonal frequency division channels, so it can support high-speed wireless data transmission without complex equalization technology, and has strong anti-fading And the ability to resist inter-symbol interference, but the main disadvantage of the OFDM system is that it has a large peak-to-average power ratio (PAPR, peak-average powerratio), which directly affects the operating cost and efficiency of the entire system. Peak-to-average ratio problem is a common problem in multi-carrier modulation. [0003] In the prior art, in order to overcome the shortcoming that the OFDM signal peak-to-average ratio is too large, there are three main types of methods: the firs...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, in order to overcome the shortcoming that the OFDM signal peak-to-average ratio is too large, there are three main types of methods: the first type of method is the clipping method, the second type of method is the sequence selection method, and the third type of method is the phase transformation method;

[0004] The principle of the first type of clipping method is simple. Generally, the probability of large peaks appearing is very small. The method of clipping is a more effective method to reduce the peak factor; but because clipping is a nonlinear processing, it will cause serious in-band Distortion and out-of-band noise, which will greatly reduce bit error performance and frequency band utilization; at the same time, although filtering after peak clipping can reduce adjacent channel interference, there will be peak regeneration, so multi-stage peak clipping filtering is often used in the prior art: For example, the TR (Tone ReseRvation) algorithm does not need to transmit sideband information. TR technology is essentially a limiting technology. Although out-of-band interference is avoided, and the complexity is relatively low without sacrificing spectrum efficiency, it will In-band noise is generated, and more importantly, the TR algorithm in the prior art still has a large amount of calculation, and the generated in-band noise is genera

Images