Efficient detection and signal parameter estimation with applications to high dynamic GPS receivers

The author presents a technique for simultaneously detecting data and estimating the parameters of a receiver carrier signal phase that is modulated by unknown data and experiencing very high Doppler, Doppler rate, etc. Such a situation arises, for example, in the case of the Global Positioning System (GPS), where the signal parameters are directly related to the position, velocity, and acceleration of the GPS receiver. The proposed scheme is based upon first estimating the received signal local (data-dependent) parameters over two consecutive bit periods, followed by detecting a possible jump in these parameters. The presence of the detected jump signifies a data transition which is then removed from the received signal. This effectively demodulated signal is then processed to provide the estimates of global (data-independent) parameters of the signal related to the position, velocity, etc. of the receiver