The impact of Doppler frequency hopping on code tracking performance is simulated. A design on Pseudo-Noise (PN) Code tracking loop aided by the carrier tracking loop according to the carrier frequency hopping pattern is proposed in this paper. This scheme can be applied in the telemetry, tracking, and commanding system which uses Direct Sequence/Frequency Hopping spread spectrum (DS/FH) hybrid spread spectrum technology. Simulations of the code tracking loop under different carrier to noise ratios are compared based on this scheme. The results show this method on PN code tracking of DS/FH signals is valid.