Block Detection of Multiple Symbol DPSK in a Statistically Unknown Time-Varying Channel

Abstract

We present a detection scheme for multiple-symbol DPSK for use in a statistically unknown time-varying channel. The scheme relies on a parametric representation of the timevarying channel, resulting in a reduction in the number of parameters required to be determined by optimizing a maximum likelihood sequence estimation (MLSE) type cost function. We also present a reduced-complexity version of the detection scheme based on sphere decoding. Analysis and simulations show good performance in Rayleigh fading over varying degrees of channel time-variation for an appropriately selected channel parameterization.

Differential dual‐hop relaying under user mobility

“…4, in Case I with symmetric channels, the BER is monotonically decreasing with (P/N 0 ) and it is consistent with the theoretical values in (22). Approximately, 3 dB performance loss is seen between coherent and non-coherent detections in this case.…”

“…The definite integral in (22) can be easily computed using numerical methods and it gives an exact value of the BER of the D-DH system under consideration in time-varying Rayleigh-fading channels.…”

“…Then P 1 = (1 − ̺)P and from (5), A = P (1 − ̺)/(̺P σ 2 1 + N 0 ). By substituting P 0 and A into (22), the optimization problem is to find the value of ̺ for which P b (E) is minimized. Since the best performance is obtained in slow-fading channels, α = 1 would be set in (22).…”

“…By substituting P 0 and A into (22), the optimization problem is to find the value of ̺ for which P b (E) is minimized. Since the best performance is obtained in slow-fading channels, α = 1 would be set in (22). Then, the minimization would be performed by a numerical exhaustive search.…”

“…The second goal in this paper is to design a multiple-symbol detection (MSD) for the D-DH relaying to improve its performance in fast-fading channels. MSD has www.ietdl.org been considered for point-to-point (P2P) communications in [17][18][19][20][21][22]. The challenge in developing MSD for AF relay networks is that, because of the complexity of the distribution of the received signal at destination, the optimum decision metric does not yield a closed-form solution.…”