Frequency offset due to Doppler shift and/or oscillator instabilities degrade receiver performance. In this paper, a family of frequency detectors for frequency offset estimation and compensation in digital receivers is introduced. The proposed detectors are best suited for frequency offset compensation of a subclass of binary continuous phase modulation with h = l/2that includes modulation schemes with nonnegative frequency pulses. For the considered modulation schemes, the modulation-induced self-noise term is absent from the variance of the frequency estimate. The estimator is nondata- and nontiming-aided and its estimation range is either half or a quarter of the bit rate (R). With larger frequency offsets, the estimators that have a ± R/2estimation range introduce a frequency ambiguity of Rthat is of no relevance to the performance of a differential detection based receiver.
All Science Journal Classification (ASJC) codes
- Electrical and Electronic Engineering
- Digital receivers
- Frequency acquisition
- Frequency detectors
- Satellite communication