Research On Microwave Interference Laser Ranging System Based On Double Polarization Modulation

Laser ranging technology plays a key role in scientific research,aerospace,engineering and transportation.Compared with traditional laser ranging methods,the microwave Interferometric Laser Ranging System Based on secondary polarization modulation has high application value because of its high measurement accuracy,low cost and small size.As an important part of the second polarization modulation laser ranging system,the optical receiving module and the microwave source module largely determine the ranging accuracy.Therefore,this paper mainly focuses on how to design optical receiving module and microwave source to optimize the ranging accuracy of ranging system.Firstly,the paper demonstrates the ranging principle and its mathematical model of the ranging system,and analyses its ranging principle.Secondly,the design and implementation process of high precision and large dynamic range optical receiving module and low phase noise X-band microwave source module as the core module of ranging system are described.The key technologies such as analog and digital isolation and micros trip line design are discussed in detail,as well as the basic architecture and selection of analog-to-digital converter,the selection and design of filter and how to control the noise of analog-to-digital converter circuit.It has a certain reference value for the practical application of engineering.Finally,the designed laser ranging system is tested experimentally.Experiments show that the optimal conversion accuracy of ADC is better than 15 bits,the phase noise of X-band microwave source is better than-100d Bc/Hz@10k Hz,the non-linearity of laser ranging system is better than±5um,and the absolute ranging accuracy(standard deviation)is better than3×10^-6m.