This report is a study aimed at deriving and evaluating algorithms, suitable for implementation in an FPGA for realtime applications, to track fast frequency hopping and/or modulated signals with a high signal-to-noise ratio. Both Least Mean Square, LMS-, and Recursive Least Squares, RLS- type frequency estimators have been designed and evaluated . The results indicate that RLS-type estimators can compete successfully with LMS in fast tracking of frequency changes despite the use of necessary time saving approximations. The simulations also indicate that the suggested algorithms can detect 180 degrees phase shifts in the carrier frequency, thus revealing the binary spreading code, and that the frequency derivative can be estimated by differentiating the frequency estimate.