Embodiments of the disclosure provide a LiDAR assembly with modularized components. The LiDAR assembly includes an integrated transmitter-receiver module assembled on a first bracket, configured to emit optical signals to an environment surrounding the LiDAR assembly and detect returned optical signals from the environment. The LiDAR assembly also includes a control module affixed on a PCB, configured to control the integrated transmitter-receiver module to emit the optical signals. The LiDAR assembly further includes an interface module affixed on a second bracket, configured to operatively couple the integrated transmitter-receiver module and the control module. The LiDAR assembly yet further includes a frame configured to position the integrated transmitter-receiver module, the control module, and the interface module at predetermined positions of the LiDAR assembly through the first bracket, the PCB, and the second bracket respectively. The integrated transmitter-receiver module is configured to be assembled to or disassembled from the frame through guideways.