Popis: |
In this paper, we designed a carrier recovery with small loop delay based on polarity-decision phase detector algorithm with large frequency acquisition range that is useful for cable modem downstream. To reduce loop delay we design a phase detector with look-up table, a digital controlled oscillator (DCO) with simple modular operation, and an index search of sine/cosine table. Simulations show that the newly designed carrier recovery can yield the bit error rate (BER) performance compared to floating-point simulated carrier recovery in large carrier frequency offset under high order quadrature amplitude modulation (QAM). |