The coherent-dispersion spectrometer (CODES) is a new exoplanet detection instrument using the radial velocity (RV) method. This attempts mainly to improve environmental sensitivity and energy utilization by using an asymmetric, common-path Sagnac interferometer instead of a traditional Michelson interferometer. In order to verify its feasibility and to choose the appropriate key parameters to obtain the optimal performance, research on data processing for the design stage of the CODES is performed by systematic simulation and analysis. First, the instrument modelling is carried out for further data analysis according to the principle of the CODES, and the reliability of the model is verified by experiments. Second, the influence of key parameters on fringe visibility is analysed systematically, which provides a certain reference for the choice of the key parameters. Third, the RV inversion method for the CODES is proposed and optimized according to the related analysis results so as to promote RV inversion precision. Finally, the recommended values for the key parameters of the CODES are given. The experimental results show that the data processing error of RV inversion is less than 0.6 m s–1 within the recommended range of key parameters. This indicates that the scheme of the CODES is reasonable and feasible, and that the proposed data processing method is effective and well matched with the instrument design.
High-sensitivity interferometers are one of the basic tools for precision measurement, and their sensitivity is limited by their shot noise limit (SNL), which is determined by vacuum fluctuations of the probe field. The quantum interferometer with novel structures can break the SNL and measure the weak signals, such as the direct observation of gravity wave signal. Combining classical interferometers and the optical parametric amplifier (OPA) can enhance the signal; meanwhile, the quantum noise is kept at the vacuum level, so that the sensitivity of the nonlinear interferometer beyond the SNL can be achieved. By analyzing in detail the influence of system parameters on the precision of quantum metrology, including the intensity of optical fields for phase sensing, the gain factor of OPA, and the losses inside and outside the interferometers, the application conditions of high-sensitivity nonlinear quantum interferometers are obtained. Quantum interferometer-based OPAs provide the direct references for the practical development of quantum precise measurement.