A robust low-complexity estimation technique for frequency-acquisition over frequency-selective channels

Conventional estimation algorithms utilize either a tone or squarewave in the preamble for frequency estimation. However, such patterns for the preamble sequence are nonoptimal when the channel is frequency-selective. Furthermore, the problem is exacerbated for packet-switched systems which require frequency synchronization on a per-packet basis. This paper presents a low-complexity frequency estimation algorithm that is robust in frequency selective fading channels. The algorithm is non-decision aided and does not require a priori frame synchronization. Compared against conventional techniques, a factor of 5-10 reduction in BER and a factor of 3 reduction in convergence time are achieved