GEO 卫星机会源近岸海面高度测量性能评估

It is potential to measure sea surface height using opportunity of source from geostationary earth orbit (GEO) satellites. Most studies focus on the experimental demonstrations, but few works comprehensively assess its perfor⁃ mance. Based on this, the paper evaluates the influence of the signal bandwidth, incoherent integration number, signal‑to‑ noise ratio (SNR) and retracking algorithm on the oceanic altimetry performance. It is found that once the incoherent inte⁃ gration number and SNR are over the optimal incoherent integration number and SNR, the improvements of the altimetry performances are insignificant. Therefore, choosing optical incoherent average number, and designing the receiver antenna gain, radio‑frequency gain, and receiver bandwidth to obtain optical SNR are needed. The fitting method can provide a bet⁃ ter precision than the interpolation method. The data from the BeiDou B3I signal and ASTRA 19.2 E satellite experiments are used to assess the GEO opportunity‑source altimetry. The experiment results show that for the incoherent average num⁃ ber and SNR over 10 000 and 7 dB, respectively, the altimetry precision of about 0.20 m and 0.10 m can be obtained, re⁃ spectively. Due to multi‑frequency or multi‑channel transmission, the spectral synthesis is proposed to improve the altime⁃ try precision. The simulation results show that the synthetized signal from 10‑channel signals of Zhongwei‑1 satellite pro⁃ vides a precision of 3.50 cm and 0.69 cm for the interpolation and fitting method.