Lower bound on spreading code tracking error under unmatched de-spreading mode

The spreading code tracking error lower bound of the coherent delay-locked loop with a generic unmatched de-spreading chip waveform is presented, and the equivalent root-mean-square bandwidth which can serve as a measure of the tracking precision in thermal noise for unmatched de-spreading mode is proposed. By using this measure, tracking performance of some typical spreading signals in global navigation satellite systems under unmatched de-spreading mode is evaluated.