Frequency deviation, time delay and phase deviation combined synchronization method of continuous phase modulation signals

Abstract

The invention belongs to the wireless communication field and provides a frequency deviation, time delay and phase deviation combined synchronization method of continuous phase modulation signals. The combined synchronization method includes the following steps of: FFT-based frequency deviation estimation; frequency deviation correction; filtering and demodulation; error signal generation: timing error signals and phase error signals are generated by using demodulation code elements and decision information; and iterative update: a timing loop and a phase-locked loop update timing and phase estimated values by using the error signals. According to the frequency deviation, time delay and phase deviation combined synchronization method of the continuous phase modulation signals, based on an FFT-based frequency deviation estimation algorithm, and a timing and phase combined estimation algorithm is used in combination, and therefore, accurate estimation can be performed on frequency deviation, timing and phase information. The method of the invention is suitable for accurate estimation of the frequency deviation, timing and phase value of the continuous phase modulation signals under a condition that frequency deviation, frequency deviation primary rate of change, time delay and phase deviation exist. The method has the advantages of elimination of false lock, excellent bit error rate (BER) performance and high estimation precision.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and specifically provides a joint synchronization method of frequency deviation, time delay and phase deviation, which is suitable for satellite communication, telemetry communication and other fields, and can realize frequency deviation, time delay and phase deviation recovery at the same time, ensuring Communication reliability. Background technique [0002] Due to the characteristics of high spectrum utilization and high power efficiency of continuous phase modulation, it has been widely used in the field of telemetry and satellite communication. However, because the phase of the CPM signal has memory characteristics, the synchronization of the CPM system is very different from the traditional method. The difference; and, CPM communication systems usually operate under low signal-to-noise ratio, which makes it more difficult to guarantee the reliability and effectiveness of sync...

AI Technical Summary

Problems solved by technology

YossefRahamim et al. used the maximum mean square soft output algorithm of decoding soft information to correct large frequency offset and phase offset, and obtain ideal bit error performance and estimation accuracy, but two-dimensional search is required, and the computational complexity is very high

Moreover, this method is more suitable for frequency offset estimation of short burst signals, but not suitable for longer transmission sequences

SayakBose proposed a non-data-assisted frequency offset, timing, and phase joint estimation algorithm, which can simultaneously recover frequency offset, timing, and phase information under the condition that the frequency offset is 10% to 20% of the code rate. This algorithm chooses the non-data-assisted frequency offset recovery algorithm because it has a large frequency locking range, so it can estimate large frequency offsets, but the algorithm has false locking and does not consider the primary change rate of frequency offset

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