Blind equalization algorithms for dual-mode CAP-QAM reception

We propose a dual-mode receiver capable of blindly demodulating both carrie rless amplitude modulation/phase modulation (CAP) and quadrature amplitude modulation (QAM) line codes. Our work is motivated by some emerging broad-b and access standards which require a receiver that can first blindly start up, then blindly distinguish between CAP and QAM, and finally decode the si gnal. The "brute force" solution to this problem would be to implement CAP and QAM receivers in parallel. However, we propose a single novel receiver based on a single equalizer that accommodates both line codes, yielding sig nificant computational savings. We describe the receiver architecture, blin d start-up methods, and line code identification algorithms, as well as com puter simulations and a laboratory experiment to verify the theoretical rec eiver behavior.