Opimzation of Full-Time and Time Shared Noncoherent Code Tracking Loops

Four noncoherent correlative code tracking loops are presented and analyzed using the Renewal Theory framework. The results include the standard noncoherent delay lock loop, the time shared version of that loop known as the tau dither loop, and modified versions of each. From the stochastic differential equation, the generalized S-curve and statistics of the equivalent noise at the input of the loop filter can be derived for each loop. Computation of the noise statistics (autocorrelation and power spectral density) allow determination of the intensity coefficients used as inputs to the renewal equations. The solutions from these steps lead to the probability density of the tracking error. Optimization of the loop structures to minimize the tracking error variance and mean time to lose lock is indicated by the simulation results.