Dual-antenna Time-delay Countermeasure against Passive Location System

This paper considers countermeasure technology of satellite passive location system based on TDOA measurement. Considering that TDOA measurement is based on the principle of time difference estimation on emitter signal received by different receivers, a technology of the same signal form spread spectrum signals with different time delay emitted by two antennas in emitter is proposed. The center vectors of the two antennas point to different directions, which makes the power ratios of the two antennas signals received by different satellites different. Then, the paper compares the theoretical derivation of the time difference estimation between traditional location method and dual-antenna time-delay technology, and introduces the satellite passive location algorithm and location error index. Finally, the simulation results show that the time difference value estimated by receivers is wrong after using the dual-antenna time-delay technology, and location error in the satellite coverage area increases effectively. The closer the angle of the antenna center vector is to the ground, the better the effect will be. It is of great significance in protecting the communication security of users.