Optimization of the Alberty and Hespelt carrier frequency error detection algorithm

Following a literature survey, the Alberty and Hespelt frequency error detection (FED) algorithm was chosen for software implementation in an all-digital demodulator. For the correct operation of this algorithm, it is desired to have symmetric bandpass filters. In this paper a simple method will be presented to ensure that the bandpass filters are fully symmetrical. Simulations show that even with symmetric bandpass filters, there is a substantial amount of tracking jitter. To overcome this problem, a smart filter has been implemented to ensure that the tracking performance is almost jitter free without increasing the error acquisition time