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Traditional in-field self-calibration techniques for some multiple channel systems, whose volume and weights are limited, are inefficient. A more simple calibration technique, employing only one assistant source in near-field and one transceiver channel, is investigated and it's unnecessary to conduct complex feed circuits behind the antennas. Furthermore, the calibration method in the principle of...
The estimation of PRIs (Pulse Repetition Interval) is the core of pulse sorting. Conventional pulse sorting algorithms, based on accumulation (such as FFT), have two shortcomings: one is its difficulty in extracting short pulse segments that are dispersed in massive pulse streams; the other is the heavy computation burden for real-time processing. Accounted for interleaving and missing of multiple...
In this paper, a scheme of a large point FFT processor with configurable transform length is proposed. To achieve a pipelined structure, the proposed scheme is designed by Radix-2 decimation-in-frequency (DIF) FFT algorithm with Single-path Delay Feedback (SDF) architecture. A prototype is implemented on Xilinx Virtex-7 XC7VX690T FPGA, which can compute 16∼128K FFT at a speed as high as 350MHZ. This...
This paper presents a model of RCS characteristic of non-uniform plasma sheltering disk target, by considering the absorption and refraction of electromagnetic wave, and combining graphic electromagnetic and ray tracking methods. The results show that: (1) RCS is reduced more than 10dB at wide-band frequency of electromagnetic wave, when the incident direction of electromagnetic wave is near the vertical...
The rotation angle estimation is useful method to extract the feature of target for the application of SAR-ATR, which would improve the efficiency of the recognition. A novel algorithm based on corner point estimation (CP) is proposed for the target rotation angle estimation in the SAR image, which extracts the feature of corner point information to achieve high precision. In the presented CP method,...
In this paper we utilize the multipath return to improve the image resolution and the signal-to-clutter ratio (SCR). Based on the modified indoor radio propagation model and the multipath scattering model, a method for localizing the focused multipath ghost is provided, then an algorithm combined the through-wall Green function with Back Propagation (BP) algorithm for association and mapping the multipath...
Radar has the capability of penetration into low-loss dry sand down to bedrock beneath. This suggests the possibility of 3D bedrock topography retrieval using SAR interferometry beneath dry sand. The influence of different penetration depths on the InSAR DEM generation is analysed initially based on a two-layer sand model. Mean-while, ICESat elevation data and the SRTM-C DEM associated with a SRTM-C...
In this paper, three different three-dimensional imaging modes, i.e., Circular Synthetic Aperture Radar (CSAR), Elevation-CSAR (E-CSAR) and Planar Circular Array, are investigated in order to compare their 3-D imaging capability in terms of spatial resolution, spectral efficiency and the region of support in the wavenumber domain. The signal spectra of the point spread function are formulated via...
This paper proposes a novel frequency discrimination method and discusses its application on anti-towed decoy. Before describing the proposed method, the principle of all phase FFT is first introduced. Then, based on the property of phase invariant, a novel frequency discrimination method based on all phase FFT is presented. Furthermore, the performance is specifically analyzed via numerical experiments...
A low-cost mini-missile is designed in this paper to substitute the real missile, which is extremely expensive. The proposed mini-missile, with compact configuration and miniaturized size, reveals RCS in the region −8°<theta<8° more than −10 dBsm at 6.5 GHz, 9 GHz and 9.5 GHz. Moreover, in the region − 8°<theta<8°, RCS of the missile at 35 GHz is more than −13 dBsm. The mini-missile has...
The multichannel in azimuth synthetic aperture radar (MC-SAR) system is very promising for high-resolution and wide-swath (HRWS) imaging, whereas Doppler centroid block estimation related to the channel phase calibration has a great influence on image quality. In order to solve the problem of the Doppler centroid block estimation, this paper proposes an effective way to improve its precision. This...
The sound recognition is considered as an effective tool to improve the performance of man-machine interaction. However, because of the non-ideal effect during the propagation and the extensive variation range of sound signal, it is quite difficult to achieve high accuracy target sound recognition for conventional sound recognition methods. In order to improve the performance of sound recognition,...
Aim at weak radar target detection and tracking in complicated background, a track-before-detect (TBD) method based on plot and track filtering is proposed. First, the plots obtained from low threshold processing are tracked and filtered, then, based on the plot and track features, multi-level thresholds are designed to eliminate false plots and tracks, finally, the target detection and tracking results...
This paper proposed a genetic algorithm based on division position coding to solve the optimization of subarray partition in monopulse application, which aims at finding the best compromise between sum and difference patterns. In the proposed method, the division position is encoded as a chromosome gene, then the initial population is randomly generated by a series of non-repeated integers, and the...
Orthogonal projection (OP) adaptive beamforming is widely applied in practical scenarios because of strong robustness. However, the performance of traditional OP adaptive beamforming would degrade severely when OP adaptive beamforming is applied at subarray level, especially in asymmetrical subarray configuration. To overcome this problem, the improved orthogonal projection (IOP) adaptive beamforming...
The superior performance of polarization sensitive array (PSA) over the single polarization array is achieved by doubling system facilities and more computational load, which limits its applications in the radar field. The alternate polarization array (APA) can reduce this problem but it still has results in the obvious fencing lobe problem. A novel design of random polarization array (RPA) is presented...
A novel radar error calibration method is proposed to easier calibrate the high-accuracy radar, which is based on the dynamic correction of the ADS-B fixed error and the change of the target echo center. Firstly, the source, types and the characteristics under radar coordinate system of ADS-B position data error are analyzed. Secondly, a model of the change of aviation target echo center is established...
Conventional Space-time adaptive processing (STAP) requires large numbers of independent and identically distributed (i.i.d.) training samples to ensure the clutter suppression performance, which is hard to be achieved in nonhomogeneous environment. In order to obtain improved clutter suppression with small training support, an iterative sparse recovery STAP algorithm is proposed in this paper. In...
The performance of the conventional Gram-Schmidt orthogonalization of covariance matrix (RGS) beamforming method will decrease significantly when non-ideal factors exists such as the appearances of fast moving interferences, array platform movement. In order to improve the robustness of interference suppression, a derivative constrained Gram-Schmidt orthogonalization of covariance matrix (CRGS) beamforming...
The range gate pull off (RGPO) jamming is considered as common electronic countermeasures (ECM) technique used to deceive radar tracking system. Under the stationary assumption, traditional slow-time pulse diversity approach needs several pulse repetition intervals (PRIs). However in the presence of RGPO, jamming signals would change fast over PRIs, making stationary hypothesis invalid. Therefore...
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