Extended Target Echo Detection Based on KLD and Wigner Matrices

Abstract

With the development of airborne radar radio frequency stealth (RFS) technology, the method of improving the RFS performance of airborne radar by optimizing target detection performance has been extensively studied. However, for wideband radar signals, the traditional point target model appears as an extended target model in the range-dimension, which is unfavorable to the detection of target echoes. To overcome the existing drawbacks, this paper devises an efficient echo detection algorithm from the perspective of information theory and random matrix. Firstly, aperiodic agile wideband radar signals are utilized to observe targets. Then, one frame of echo signals in the same range gate is reconstructed into a data form conforming to the Wigner matrix spectral decomposition. Finally, according to the signal detection theory, Kullback-Leibler Divergence (KLD) is used as the test statistic to complete the echo detection of the stealthy extended targets. By statistical analysis and comparison with other established echo detection algorithms, simulation results manifest that the proposed algorithm has superior detection performance and strong robustness, which not only makes up for the deficiency of traditional narrowband radar detection algorithms, but also increases the detection probability of radar system when it is faced with stealthy extended targets.

Research on the Sequential Difference Histogram Failure Principle Applied to the Signal Design of Radio Frequency Stealth Radar

“…The interval distribution of PRI causes the number of accumulated pulses in the histogram to be less than the threshold value. 3 The SDIF sorting algorithm generates incorrect PRI estimates. To address the measurement error of the arrival time of signal pulses by the electronic reconnaissance receiver, a tolerance range is usually set in the sorting algorithm.…”

“…In the special case, if the finite elements in sets ∆T 1 and ∆T 2 are arranged in an equal difference and repeated cyclically, the signal is a PRI slide signal. 3 The elements in sets A and B are pseudo-random code sequences or random sequences, and the signal is a random PRI signal. In the special case, if the elements in sets ∆T 1 and ∆T 2 are random sequences that obey a small interval distribution, the signal is a PRI jitter signal.…”

“…The prerequisite for electronic countermeasures is electronic reconnaissance [2]. As the function of electronic reconnaissance systems becomes increasingly comprehensive and precise, radio frequency (RF) stealth radar is becoming a research hotspot to counter the electronic reconnaissance systems in modern electronic countermeasures [3]. According to the signal detection process of electronic reconnaissance systems, RF stealth radar [4] mainly has three countermeasures, anti-interception [5][6][7], antisorting [8] and anti-identification, to achieve RF stealth.…”

Distributed Target Detection in Unknown Interference

“…Note that with the improvement of radar resolution, a target usually occupies successive multiple range bins. In other words, a target is usually a distributed target [ 21 , 22 ]. However, to the best of our knowledge, no effective detector has been proposed for the problem of detecting a distributed target in completely unknown interference.…”

An Entropy-Based Anti-Noise Method for Reducing Ranging Error in Photon Counting Lidar

“…Therefore, a more robust anti-noise technology needs to be established. Entropy is an important tool to quantitatively evaluate the uncertainty of random events, and recently many technologies using entropy to improve detection performance have been developed in radar, ultra-wide bandwidth ranging and location, fuzzy clustering, and cypher system [18][19][20][21]. For the range measurement process of photon counting lidar, noise is a stationary random process and signal is a nonstationary random process, which means that the fluctuation of noise photon events (PEs) is completely random and that of signal PEs is related to laser pulse, i.e., the uncertainty of the fluctuation among noise events is much higher.…”