In the TDOA target generation system， microwave photon links are used to transmit multi-channel and multi-band target simulation signals containing accurate TDOA information. To ensure the accuracy of TDOA information is enough， it is necessary to accurately measure the propagation delay of the target simulation signal through the photon link. A novel method for measuring the propagation delay of photon link is proposed in this paper， which uses a dedicated delay measurement chip based on the gate delay counting principle to achieve high-resolution and high-precision measurement. By occupying the same optical transmission channel of a single fiber through time sharing between the delay measurement signal and the target simulation signal， the measurement of the propagation delay and the transmission of the target simulation signal are achieved for a photon link， it meets the hardware requirements for accurately measuring the propagation delay of photon link mechanically. The experimental results show that this method can accurately measure the propagation delay of the TDOA target simulation signal through the photon link， with an error of less than 1ns， which is one order of magnitude higher than the TDOA measurement accuracy of the sensor， meets the measurement accuracy requirement of the system.

From the perspective of active and passive radar target tracking data fusion， this paper summarizes the measurement error distribution characteristics of discrete space distributed active and passive radars for the same air target through a qualitative analysis method of radar measurement error combing mathematical approximation processing and geometric figure analysis. A novel fusion method for active and passive radar target measurement data is proposed when the angle between the target and the deployment point of the active and passive radar is small. By optimizing the weighting coefficient allocation criteria to fully combine the advantages of the each radar measurement accuracy， the target tracking data is fused in the geosphere coordinate system to improve measurement accuracy， the target fusion data is smoothed using the extended Kalman filter algorithm. The simulation results show that this method can combine the advantages of active and passive radar target measurement accuracy， reduce the measurement error ellipse after target data fusion， and overall improve the measurement accuracy of fused target tracking data.