Design Of General Processing Platform For Li Dar Based On FPGA

Lidar has continued to innovate and develop in recent years.In various application systems,different algorithms are used to process data to obtain the information contained in the signal.For radar systems,data transmission efficiency,system inheritability and portability need to be considered.As an extremely important part of the lidar system,the signal processor involves functions such as signal acquisition,storage,data transmission,and command control.These functions are integrated and designed to make the function design more general,which is convenient for the transplantation and inheritance of the entire system.Based on the above requirements for lidar,combined with previous design experience and achievements,a general processing platform for lidar is designed.Since the signal in the signal acquisition is roughly classified into two parts,the analog signal and the single-photon signal,two acquisition boards are designed in the system to perform high-speed signal acquisition and single-photon signal counting respectively.An interface board is used to control the system,with a power board and a data recording board to form the entire system.The whole system is presented in a VPX chassis with six card slots,with reserved processing modules to accomplish the general and miniaturized design requirements of the system.Firstly,according to the performance characteristics of the general processing platform of lidar,this thesis introduces the theory of single photon counting,signal acquisition,highspeed data transmission,etc.,and carries out the design of the board card int the system according to the characteristics of the chip.According to the scheme of each functional board in this system,the overall structure of the two signal acquisition boards is determined,and the core device selection,schematic design,PCB layout design and board making of each functional module are carried out.Perform single-board testing on the hardware of the functional board to ensure that the board works normally and that each functional module is powered normally.Secondly,according to the system performance indicators,the realization and verification of the logic codes of the high-speed acquisition,clock module,data storage module,data transmission module and single-photon counting module are completed.Finally,all functions of the system are realized and verified.In the design,the method of combining serial-parallel data and double data rate sampling is used to realize the counting of single photon data.In the test,the pulse signal with a minimum pulse width of 2.5ns is accurately counted,avoiding the interference of noise on photon data.It provides a new solution and design scheme for the use of single-photon pulse counting in other application scenarios.Perform functional verification in the entire system,including high-speed signal acquisition,single-photon counting,real-time display,and data storage.After extensive testing,the whole system runs stably,can be collected and stored in various scenarios,the interface board can control the system normally,and can also complete the control of INS and GPS.The overall design meets the requirements of the general processing platform for lidar,realizes the versatility and inheritability of the system,and provides a reference idea for the design of other similar systems in subsequent research.