On Burst-Mode Synchronization of SOQPSK

In this paper, we present a maximum likelihood synchronization algorithm which jointly estimates frequency offset, symbol timing and carrier phase for shaped-offset quadrature phase-shift keying (SOQPSK) signals. We have considered a burst-mode transmission scenario in which a known and optimized training sequence is embedded in the beginning of each burst for the purpose of data-aided (DA) synchronization in a feedforward structure. The proposed algorithm first estimates the frequency offset independently from other parameters. The estimated frequency is then used to derive the symbol timing which is followed by the carrier phase estimation. The mean-squared error (MSE) of the proposed algorithm is computed via simulations. The results show that the proposed algorithm performs near the theoretical Cramer-Rao bound (CRB) at signal-to-noise ratios (SNRs) as low as 0 dB.

[1]  H. Meyr,et al.  A fully digital feedforward MSK demodulator with joint frequency offset and symbol timing estimation for burst mode mobile radio , 1993 .

[2]  Mark J. Dapper,et al.  SBPSK: A Robust Bandwidth-Efficient Modulation for Hard-Limited Channels , 1984, MILCOM 1984 - IEEE Military Communications Conference.

[3]  Marek Gasior,et al.  Improving FFT Frequency Measurement Resolution by Parabolic and Gaussian Spectrum Interpolation , 2004 .

[4]  T. Aulin,et al.  Continuous Phase Modulation - Part I: Full Response Signaling , 1981, IEEE Transactions on Communications.

[5]  Erik Perrins,et al.  The Cramér-Rao bound for data-aided synchronization of SOQPSK , 2012, MILCOM 2012 - 2012 IEEE Military Communications Conference.

[6]  Umberto Mengali,et al.  Joint phase and timing recovery with CPM signals , 1997, Proceedings of ICC'97 - International Conference on Communications.

[7]  Mark Geoghegan.  Challenges of Implementing an iNET Transceiver for the Radio Access Network Standard (RANS) , 2011 .

[8]  Michele Morelli,et al.  Feedforward joint phase and timing estimation for MSK - type signals , 2001, Eur. Trans. Telecommun..

[9]  E. Perrins,et al.  Decision-Directed Symbol Timing Recovery for SOQPSK , 2009, IEEE Transactions on Aerospace and Electronic Systems.

[10]  Umberto Mengali,et al.  Feedforward carrier frequency estimation with MSK-type signals , 1998, IEEE Communications Letters.

[11]  Prashanth Chandran,et al.  Symbol Timing Recovery for CPM with Correlated Data Symbols , 2009, IEEE Transactions on Communications.

[12]  M.K. Nezami.  Techniques for acquiring and tracking MIL-STD-181B signals , 2002, MILCOM 2002. Proceedings.