Time Domain Power Law Noise And Phase Noise Synthesis For GPS Code Analysis

System simulation is extremely important for verification of large-scale integrated chipsets for wireless applications, such as front-end circuit design for wireless receiver. In order to perform the system level simulation, models for each circuit module as well as disturbance are required.Power low noise (1/f~αNoise) and phase noise are two common interferences in analog circuit. 1/f~αNoise is an important limit factor for radio frequency receiver and base band analog circuit. Phase noise is normally found in phase locked loop and local oscillators, which increase the phase error, multi-channel interference and bit error rates. Two current techniques for generating discrete sequence of 1/f~αnoise are summarized. One is based on finite impulse response (FIR) and infinite impulse response (IIR) filter, the other is based on the structure of several parallel first-order low pass filters. Comparisons will be made between the two methods in point of running time and relative error. Based on the modeling principle of low-pass filters structure for 1/f noise generation, a time-domain model is proposed for phase noise synthesis. The main idea is to separate the noise generation process into different segments and use the low-pass filters structure to process the noise separately in each individual segment. The MATLAB simulation environment was selected because of its wide application for development and evaluation of communication algorithms.Besides, a simplified simulation environment for GPS coarse/acquisition (C/A) code tracking is set up in MATLAB to evaluate the influence of phase noise on C/A code tracking process. Further research is made to find the relationship between the phase noise characterizations and the influences.The simulation results are verified both in frequency domain and time domain. Conclusions can be drawn that the proposed phase noise model has the following advantages: simple, parametric and independent. It can aid system simulation and research on noise reduction.