A feed-forward technique for initial reference parameter estimation in burst mode PSK demodulation

In burst mode communications, fast and efficient estimation of demodulator reference parameters is a key issue as receivers must be able to correctly synchronize on short bursts of data. To do so, it is possible to use a prea mble in each data burst as long as the algorithms used require very short p reambles and therefore do not degrade communication efficiency excessively. If a preamble is used, in fact, estimation performance is better than when a fully modulated carrier is used. In this paper the authors propose a nov el feedforward technique for reference parameter recovery in PSK demodulati on, the main characteristics of which are robustness to frequency offsets, shea acquisition time and ease of implementation, even with low-cost digita l hardware. The technique is based an a very short special carrier preamble modulated by a known pattern, which allows the reference parameters to be estimated simultaneously and directly.