Data aided symbol timing system for precoded continuous phase modulated signals

Abstract

Data aided carrier phase and symbol timing synchronizers are implemented at baseband as digital modulators isolating input signal inphase and quadrature component signals fed into inphase and quadrature. Laurent transforms that function as data detector to provide odd and even data bit multiplexed output data signal while cross coupling the inphase and quadrature transformed outputs for removing data modulation in error signals to correct phase errors and timing errors in the received signal so as to provide reliable data demodulation of noisy received signals having dynamic carrier phase and symbol timing errors as found in continuous phase modulation communications systems such as Gaussian minimum shift keying communications systems.

Description

STATEMENT OF GOVERNMENT INTEREST[0001]The invention was made with Government support under contract No. F04701-93-C-0094 by the Department of the Air Force. The Government has certain rights in the invention.REFERENCE TO RELATED APPLICATION[0002]The present application is related to applicant's copending application entitled Data Aided Carrier Phase Timing Tracking System for Precoded Continuous Phase Modulated Signals, Ser. No. 09 / 694,650, filed Oct. 24, 2000, by the same inventors.FIELD OF THE INVENTION[0003]The invention relates to the field of continuous phase modulation communications systems. More particularly, the present invention relates to symbol time tracking for continues phase modulations communications systems, such as Gaussian minimum shift keying communications systems having small bandwidth time products.BACKGROUND OF THE INVENTION[0004]In synchronous digital data communication systems, the carrier phase and symbol timing of the received signal must be acquired and ...

AI Technical Summary

Benefits of technology

This approach enables non-degraded bit error rate (BER) performance with reduced design complexity, allowing for accurate symbol time and carrier phase tracking even in noisy conditions, and improves power and spectral efficiency in CPM systems.

Problems solved by technology

The use of CPM signals in communications systems can potentially achieve significant improvement in both power and spectral efficiency over other conventional modulation techniques, at the cost of a moderate increase in receiver complexity.

Often, symbol time tracking and carrier phase tracking limit the performance of CPM systems.

These synchronizers often lose track during noisy communications.

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