The paper addresses the realization of anti-stealth radar and the problems which modern radars are confronted with. With the application of spread spectrum technology to radars, the capability of anti-stealth and anti-jamming is improved. Signal-to-noise (SNR) of the receiver increases through raising the launching power. Intercept probability decreases by transmitting multiple PN codes. Range of radar detector increases on condition that the intercept probability is unchanged. Simulation results show the validity of the proposed method.

Orthogonal frequency-division multiplexing (OFDM) combines the advantages of high performance and relatively low implementation complexity. However, for reliable coherent detection of the input signal, the OFDM receiver needs accurate channel information. The Doppler shift of fast-fading channels will generate inter-carrier interference (ICI) and, hence, degrade the performance of orthogonal frequency-division multiplexing (OFDM) systems. In this paper, we present regularized total least-squares (RTLS) scheme to eliminate the ICI and noise. A closed-form mathematical expression has been derived to express the channel estimation. It has been shown that the proposed channel estimation and data detect can effectively eliminate the ICI effect.

In this paper, a novel netted radar system is designed to reduce the influence of mutual interference between signals. The emission signals of all stations are assigned the orthogonal PN codes. Because of the good autocorrelation and cross-correlation properties, mutual interference becomes weaker and signals from different stations could be separated by the preassigned PN codes. At the same time, the spectrum of the emission signal is spreaded, the peak-to-mean envelope power ratio (PMEPR) and the intercepted probability of the signals descend therefore. Simulation results show the good performance of the proposed approach.

In order to enhance the capability of anti-jamming and Low Probability of Intercept (LPI) of radar system, spread spectrum signals are designed for modern radar system. Emission signal is coded with PN codes at the transmitting terminal. Spectrum of signal is spreaded and multi-signal mixed together, so it is not easy to intercept. At the receiving terminal, undesired signals are spreaded when dispreading desired signal. Signal to noise ratio (SNR) of the received signals is raised after despreading, so the detection range broadens. Computer simulations verify the good performance of the proposed approach.