Carrier synchronisation for multiple symbol Trellis-coded CPFSK in burst-mode transmission

摘要

A carrier synchronisation technique for multiple symbol Trellis-coded continuous phase frequency shift keying (MSTC-CPFSK) system in burst-mode transmission is proposed. For the synchronisation technique, a joint data-aided (DA) acquisition and phase-locked loop (PLL) tracking algorithm is presented. First, an all-zero sequence is utilised as a pilot for DA acquisition, where the modulated pilot waveform is a direct current (DC) signal, eliminating the operation of modulation removal; and then, a second-order PLL structure is introduced for tracking processing, and we make an analysis of the tracking performance by calculating the equivalent Cramer-Rao bound (ECRB) for the second-order PLL structure; subsequently, we extend the obtained result to any order PLL structures; moreover, the ECRB for the MSTC-CPFSK system is also derived through arithmetical calculation; finally, some numerical results are given to verify the performance of the authors presented synchronisation algorithm, and the simulations illustrate that their algorithm can improve the throughput compared with the classical DA-only algorithm.