To further trace the error caused by the magnetic field coupling process of the time-gate displacement sensor, the coupling characteristics of the time-gate displacement sensor in the construction field are studied. A new linear time-gate displacement sensor based on the exponential planar coil structure is developed. The mathematical model of the magnetic field constructed by sensor engineering is formulated. The influence of the sensor coupling gap on the magnetic field distribution of the coil coupling plane is analyzed, and the coupling characteristics of the coil of different shapes are studied. According to the coupling characteristics of the sensor, a new linear time-gate displacement sensor measurement model is formulated. The electromagnetic field finite element simulation and simulation error analysis are carried out on the model, and the optimal sensing gap of the structure is 0. 4 mm. The structural error of the sensor is traced and analyzed, and the structure of the sensor was further optimized. An experimental platform is established by using the double-layer PCB winding process to process sensor fixed and moving ruler. Comparative experiments are implemented on sensor prototypes before and after optimization. The experimental results show that the new linear time-gate displacement sensor based on exponential plane coil structure can effectively suppress the four errors of the sensor, and the original measurement accuracy of the newly developed sensor prototype is improved by 45. 8% on the original basis.