A 16APSK signal carrier phase synchronization method and a judgment locking method thereof

Abstract

The invention provides a 16APSK signal carrier phase synchronization and locking judgment method, and aims to provide a method capable of reducing the number of phase ambiguity of 16APSK and reducingthe subsequent processing complexity of a demodulator. The invention is realized through the following technical scheme: the method comprises the following steps of: obtaining a sample; in the 16APSKcarrier synchronization, a 16APSK carrier is synchronized, firstly, the hard decision module obtains hard decision values of demodulation constellation points according to carrier synchronization output signals; secondly, the phase discriminator demodulates an angle difference between a carrier synchronous output signal and a hard decision value of a constellation point; EXTRACTING PHASE ERROR SIGNALS, smooth filtering is carried out on the phase error signal through a loop filter; and then the voltage-controlled oscillator NCO generates a corresponding phase compensation value according to anoutput signal of the loop filter and the phase deviation indication output by the 16APSK carrier synchronous judgment locking branch joint judgment module, and finally, the carrier synchronous inputsignal performs phase compensation according to the phase compensation value to obtain a carrier synchronous output signal.

Description

technical field [0001] The invention relates to the field of satellite communication, in particular to a carrier synchronization method for high-order modulation in high-speed satellite communication, and in particular to a carrier synchronization method suitable for 16APSK and its locking method. Background technique [0002] With the continuous development of satellite communication and the continuous expansion of satellite communication services, the demand for the amount of data to be transmitted continues to increase. This makes it necessary to use a modulation method with high spectrum efficiency under limited spectrum resources. Since the satellite channel is a typical nonlinear channel, compared with the low-order modulation method, the high-order modulation signal will face more serious signal nonlinear distortion. The traditional high-order QAM modulation (such as 16QAM) has a large constellation amplitude and is very sensitive to the nonlinearity of the channel. ...

AI Technical Summary

Problems solved by technology

In the process of signal propagation, the rapid change of channel characteristics, the asynchronous clock of the receiving end and the clock of the sending end, and the Doppler frequency shift caused by motion all cause the signal spectrum received by the receiving end to deviate from the center point, so that The down-converted baseband signal produces a randomly changing frequency offset, and the signal will introduce random phase jitter during transmission, so that the baseband signal at the receiving end will inevitably have frequency offset and phase offset, resulting in random phase before signal demodulation error

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