Low-peak-to-average-ratio wireless optical transmission method based on dynamic scalar regulation

Abstract

The invention discloses a low-peak-to-average-ratio wireless optical transmission method based on dynamic scalar regulation. The low-peak-to-average-ratio wireless optical transmission method based on dynamic scalar regulation comprises the steps that different scalar regulation coefficients are selected according to time domain peak values of all OFDM symbols, the symbols with extremely large peak values are compressed to a certain extent, in this way, the PAPR of signals of a whole frame is lowered, and therefore the transmission performance is improved; a user just needs to measure the average power of the received symbols at the receiving end so as to estimate the multiplied regulation coefficient, and the method is easy to realize; requirements of a system for power amplifiers and the degree of linearity of LED lamps are lowered due to the fact that the PAPR is lowered, nonlinear distortion of signals in an electric and optical domain is reduced, and the receiving performance of the system is improved; the direct-current bias needing to be added at the transmitting end is reduced due to the fact that the PAPR is lowered, and power consumption of the system is reduced.

Description

technical field [0001] The invention relates to a low peak-to-average ratio wireless optical transmission method based on dynamic scalar adjustment, which belongs to the wireless optical communication technology. Background technique [0002] Due to its rich spectrum resources, good communication security, high transmission power, and less electromagnetic radiation, wireless optical communication has become a research hotspot in the field of communication in recent years. In order to achieve high-speed data transmission in wireless optical communication and reduce inter-symbol interference (ISI), OFDM modulation is introduced in wireless optical communication, and high-speed data transmission can be provided by sending modulated symbols on orthogonal subcarriers in parallel. Combat multipath effects. [0003] Intensity modulation / direct detection (IM / DD) is often used in wireless optical communication, so the time-domain transmitted signal after OFDM modulation needs to be ...

AI Technical Summary

Problems solved by technology

This can not only ensure that the time domain signal sent is a positive real signal, but also reduce the transmission power and save resources, but the frequency utilization rate is low, and N subcarriers can only send N / 4 symbols. This method sacrifices the data rate for The trade-off avoids the power loss of adding a DC bias

DCO-OFDM is to add a DC bias to the OFDM modulated signal to make the signal a positive value. This method is simple to implement and has a high frequency utilization rate, but increases the DC power consumption.

[0004] Similar to the OFDM system in radio frequency communication, the OFDM system in wireless optical communication also has the problem of high signal peak-to-average power ratio

A high PAPR will put forward high requirements on the linearity of the power amplifier at the transmitter. In an optical OFDM system, an excessively high PAPR will not only impose higher requirements on the linearity of the LED lamp but also the power amplifier. Because the power amplifier and the LED lamp Non-linear characteristics can cause nonlinear distortion, which can seriously degrade the overall performance of the system

At the same time, in the wireless optical communication DCO-OFDM system, high PAPR will also lead to an increase in the required DC bias, thereby increasing system power consumption

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