Method for modulating and demodulating ultrashort wave advanced mapping

Abstract

The invention relates to a method for modulating and demodulating ultrashort wave advanced mapping, which comprises the following steps: firstly, converting eight binary bits into four complex numbers by a sender through complex mapping; secondly, performing advanced mapping on the four complex numbers to obtain a new complex vector containing eight new complex numbers; and finally performing quaternary modulation on each new complex number in the new complex vector to obtain eight quaternary modulation waveforms. A receiver detects the received eight quaternary modulation waveforms one by one to obtain a receiving new complex vector containing eight receiving new complex numbers, then performs related operations between the receiving new complex vector and a complex conjugate vector generated by the receiver, estimates out the four complex numbers sent by the sender according to the results of the related operations, and finally uses the mapping relation between the eight binary bits of the sender and the four complex numbers to restore the eight binary bits. By using the method, the receiver obtains additional demodulation signal-to-noise ratio gain under the condition of not reducing the information transmission rate to further increase the communication distance of an ultrashort wave radio communication system.

Description

technical field [0001] The invention relates to a modulation and demodulation method for a transceiver of an ultrashort wave wireless communication system, in particular to a method for realizing ultrashort wave high-order mapping modulation and demodulation by designing mapping conversion rules between information bits and transmission waveforms. Background technique [0002] The communication distance of an ultrashort wave wireless communication system is generally determined by the propagation characteristics of electromagnetic waves in this frequency band, antenna gain, transmission power, and baseband signal processing methods. In the case of a given frequency band, transceiver antenna and transmit power, the communication distance mainly depends on the baseband signal processing method adopted. [0003] In the baseband signal processing method, the signal design that affects the communication distance mainly includes the channel codec method and the modulation and demo...

AI Technical Summary

Problems solved by technology

On the other hand, the propagation characteristics of electromagnetic waves in the ultra-short wave band (30MHz-3GHz) cannot reach the transmission distance of ionospheric propagation in the short-wave frequency band (3MHz-30MHz), and many applications in this frequency band hope to achieve longer communication distances

In the process of solving these problems, some new technologies such as Trellis-Coded Modulation (TCM: Trellis-Coded Modulation) can provide some solutions, which are characterized by being able to improve the receiving signal-to-noise ratio of the system without increasing the transmission bandwidth. Performance, but the signal-to-noise ratio improvement that TCM can provide is only 3-6dB, and with the improvement of the signal-to-noise ratio, the implementation complexity increases significantly

Images