Patent ID: 6671342
Filing Date: 2003-12-30
Classification: H04B,H04L,H04N

Abstract:
In an offset QAM receiver that recovers in-phase signals sampled at in-phase sampling times and quadrature-phase signals sampled at quadrature-phase sampling times, a method for detecting the phase of the recovered signals comprising:separating the in-phase signals into a first data stream at the in-phase sampling times and a second data stream at the quadrature-phase sampling times; separating the quadrature-phase signals into a third data stream at the quadrature-phase sampling times and a fourth data stream at the in-phase sampling times; generating a fifth data stream representing tentative decisions from the first data stream; generating a sixth data steam representing tentative decisions from the third data stream; comparing the first and fifth data streams to generate a first error signal; comparing the third and sixth data streams to generate a second error signal; combining the first error signal and the fourth data stream to form a first phase error signal; and combining the second error signal and the second data stream to form a second phase error signal.