An adaptive algorithm for reducing phase error in digital carrier recovery for high-order QAM signals

摘要

References(6) This paper describes an adaptive software aided technique for phase error reduction in digital carrier recovery (CR)for high-order Quadrature Amplitude Modulation (QAM). Simulations and analytical results illustrate a phase error variance improvement of at least 30dB compared to conventional CR, leading to more than 3dB processing gain enhancement for high-order QAM, using the simple 4th power phase estimation technique. The new technique can be employed to improve the performance of any CR loop, at the cost of slight complexity overhead independent of the modulation order.