Abstract:

The expressions of non-conjugated and conjugated secondorder cyclic cumulants are deduced based on complexvalued binary phase shift keying (BPSK) signals. The influence of different timedelays on the characteristics of cyclic frequency is studied, and the independent algorithms are proposed to estimate carrier frequency and chip width. In other words, carrier frequency can be estimated based on nonconjugated secondorder cyclic cumulants with a timedelay to be zero|while chip width can be estimated based on conjugated  second order cyclic cumulants with a timedelay to be nonzero. To improve the performance, the optimum timedelay is deduced, and then a much better chip width estimation algorithm is proposed. Simulations verify that though the performance of the proposed carrierfrequency algorithm has 2 dB loss, computational complexity is much simpler than the cyclicspectrum algorithm, and the performance of the proposed chip width algorithm has a more than 5 dB increase compared with the cyclicspectrum algorithm.