Carrier phase tracking in digital radio communications

Computationally efficient schemes which can accurately estimate the unbiased phase offset of a quadrature phase shift keying carrier at low E_b/N₀ are described, with the computational requirements for each scheme. The phase error variance for the Viterbi and proposed schemes, operating in a Gaussian channel, are evaluated and compared with the Cramer-Rao lower bound. Acquisition of the tracking process is determined by computer simulation