Simulation And Experimental Investigation Of Radar-lidar System

In recent years, with the trend of the detection’s environment being more and more complex and the target also being multiplex, single detection model has been unable to meet the actual needs. In the meantime, the laser detection precision has been affected by the weather which is hard to be removed, the performance of microwave detection has also been limited by electronic bottlenecks. Therefore, how to properly combine these two so that they can learn from each other’s strong points to offset others’ own weakness which can better adapt to the future detection’s requirements needing to be explored currently. This paper proposes a design of radar-lidar ranging system, through the theoretical research and experiments to demonstrate the feasibility of this system.Based on the basic principle of FMCW Laser Radar, which also combine with the existing DDS signal generator, this paper proposes a principle of quasi-FMCW radar-lidar ranging system which the frequency changes by steps, and also desire the system. Derived by calculating and modeling, the paper represent the corresponding theoretical explanations and ranging formula and the resolution formula. Aiming to give a detailed theoretical analysis and simulation about the signal generator, through simulation study this paper investigate all the major parameters of the signal generator which may influence the system’s range accuracy, operating range, range resolution, such as the number of comb of the optical frequency comb, the repetition frequency, the jitter of the repetition frequency, the jitter of the OFC’s power, the response time of the Fabry-Perot Tunable Filter, as well as the duration of each comb. Finally, this paper show the optimum design parameters respectively, and then show the rules of rational reason of the radarlidar system.In the experiments, first, this paper use the theory of DPMZM’s carrier-suppressed SSB to design a optical frequency comb generation system, through the experimental system, this paper get a comb with 9 comb and 0.2359 dB flatness. While taking advantage of the generating optical frequency comb, using the F-P cavity filter to complete the signal generation verification test, the final result obtain a FMCW with two frequency steps changing. The result prove that combine OFC and Fabry-Perot Tunable Filter can obtain quasi-FMCW with the frequency changing by steps. Finally, take advantage of the intensity modulator’s double sideband modulation theory, this paper design a quasi-FMCW ranging experiment in the laser band and the theoretical analysis agrees well with experiment results which indirect proof of the radar-lidar system’s theory correctness and operability.