One-step code-phase tracking method for long-code navigation systems

In this paper we propose a novel code-phase tracking method for satellite navigation systems. We consider long-code systems, where the navigation message is spread by a code with period much longer than the symbol period. The proposed method tracks the delay in one step and no iterative processing is needed. The estimation is performed using a MSE criterion. The received signal amplitude can also be tracked. The proposed algorithm achieves in a single step the same performance as the traditional early-late receiver after several iterations. Moreover, no signal interpolation is required. Hence, the complexity is lower and a single sample per chip is sufficient for the estimation.