Data fusion of target characteristic in multistatic passive radar

Radar cross section(RCS)is an important attribute of radar targets and has been widely used in automatic target recognition(ATR).In a passive radar,only the RCS multiplied by a coefficient is available due to the unknown transmitting parameters.For different transmitter-receiver(bistatic)pairs,the coefficients are different.Thus,the recovered RCS in different transmitter-receiver(bistatic)pairs cannot be fused for further use.In this paper,we propose a quantity named quasi-echo-power(QEP)as well as a method for eliminating differences of this quantity among different transmitter-receiver(bistatic)pairs.The QEP is defined as the target echo power after being compensated for distance and pattern propagation factor.The proposed method estimates the station difference coefficients(SDCs)of transmitter-receiver(bistatic)pairs relative to the reference transmitter-receiver(bistatic)pair first.Then,it compensates the QEP and gets the compensated QEP.The compensated QEP possesses a linear relationship with the target RCS.Statistical analyses on the simulated and real-life QEP data show that the proposed method can effectively estimate the SDC between different stations,and the compensated QEP from different receiving stations has the same distribution characteristics for the same target.

Doppler Signal Simulation and Analytic System for Radio Fuze

A system for simulating and analyzing the Doppler signal of air-target fuse is established by constructing two parts： Doppler signal testing with simulation and Doppler signal analysis. The first part establishes the near-field target characteristic model where the Doppler spectrum in different encounter condition is obtained. The second part mainly deals with a general purpose hardware platform to obtain and process the Doppler signal as well as a software to estimate the Doppler spectrum. The model and the result of Doppler spectrum analysis were verified by experiments.

Study on the Technique of Passive Millimeter Wave Detector

In order to initiate the flight immediately when it reaches the top of the pedrail vehicle, technical parameters of radiometer have been designed and speedy effective signal processing method has been adopted. After analyzing the difference of signal characteristic between the main jam and the target, a method of identifying target in time domain is given. The target distinguishing rules are set up by extracting the magnitude, the slope and the width of the signal, combining with distinguishing the dimension of the target. The result of the theoretic analysis shows that the detecting scheme adopted can ensure the detector to identify and orientate the pedrail vehi cle＇s top armour, as well as control the detonation precisely.

Reconstruction of characteristic parameters of underwaterelastic composite tubular targets

By using a ray method, a physical model that the backscattering of a tube is simplilied into reflection of a plane wave on layered media is suggested and reconstruction formulas of the parameters of a metallic tube covered with sound-absorbing materials under the conditions of high frequency, fard field and thin tube are given. The internal and external radii of an aluminium tube filled by water or air and thickness of the covered material are reconstructed by using computer simulation and experimellts. The theoretical tesults obtained by this method are supported by experiments.