Carrier frequency and frequency rate-of-change estimators with preamble-postamble pilot symbol distribution

Digital burst-mode transmission is ordinary in a few wireless communications systems such as satellite time-division multiple access (TDMA) and terrestrial mobile cellular radio. In those situations the received carrier may be affected by non-negligible Doppler shift and Doppler rate due to relative motion between transmitter and receiver. This contribution is concerned with the introduction of new enhanced-accuracy and low-complexity carrier Doppler shift and Doppler rate estimators which exploit the presence of (known) pilot symbols in the burst. In particular, we consider a special burst format encompassing two groups of consecutive pilot symbols placed at the beginning (preamble) and at the end (postamble) of each packet. The performance of the proposed estimation schemes is assessed by analysis and by simulation, and is compared to the relevant Cramer-Rao bounds. The particular pilot arrangement is shown to provide enhanced estimation accuracy at low signal to noise ratio as compared to conventional (preamble-only) estimation.