A selection method of frequency combination in MF-INSAR system

As an extension of the Interferometric Synthetic aperture radar (InSAR), the multi-frequency InSAR can realize high-accuracy elevation extraction of the steep terrain. Though the maximum likelihood estimation (MLE) is widely used in the signal processing of multi-frequency InSAR, the performance of this method can be influenced by the selection of frequency combination. At the beginning, this paper analyses the elevation estimated effectiveness of different frequency combinations from the aspect of Cramer-Rao Lower Bound (CRLB). Then, it calculates the ambiguity cycle as a further filter for the optimal frequency combination. Finally, this paper discusses the adaptability to the phase noise with the help of Monte Carlo simulation strategy. In consideration of these three aspects, a selection method of frequency combination is proposed, and further simulation results are provided in quantity. Relevant researches can be used in the design of multi-frequency InSAR system.