P-band space-based bistatic radar can globally detect and track moving targets with very strong penetration ability and has become an important research field in the radar community recently. This paper discusses the ...
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ISBN:
(纸本)9781849199940
P-band space-based bistatic radar can globally detect and track moving targets with very strong penetration ability and has become an important research field in the radar community recently. This paper discusses the problems of the designing the P-band bistatic space-based radar such as the characteristics analysis of the target RCS, the antenna size analysis, the effect of ionosphere and the influence of sea clutter characteristics. The numerical results were used to verify the theoretical analysis.
High resolution medium penetrating imaging radar is a kind of important equipment which can be widely used in military, security, construction and other fields. For the sake of imaging the target buried in the medium ...
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ISBN:
(纸本)9781849199940
High resolution medium penetrating imaging radar is a kind of important equipment which can be widely used in military, security, construction and other fields. For the sake of imaging the target buried in the medium fast and in high resolution, this paper analyzes the theory of high resolution medium penetrating imaging, proposes two dimensional fast scan method which combine column staggered array antenna with lead rail, presents the process of near field synthetic aperture imaging and structure of the prototype. In the end, the result of imaging test of the prototype is given. The prototype can penetrate 2.5cm board and image the small target, the imaging resolution is better than 1cm.
FMCW radar with deramping technique has many advantages comparing to traditional pulse radar. But the expressing of signal error becomes more complicated. The distortions on amplitude and phase are unavoidable for wid...
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ISBN:
(纸本)9781849199940
FMCW radar with deramping technique has many advantages comparing to traditional pulse radar. But the expressing of signal error becomes more complicated. The distortions on amplitude and phase are unavoidable for wide bandwidth and wide pulse signal, which have a serious impact on the imaging quality. Aiming at the problem of signal error correction, the echo signal model of FMCW radar with amplitude-phase error was established in this paper. The analysis of error estimation and correction were investigated in detail especially for non-linear phase error. And a practical solution was presented to reduce the effects from the distortions. The processing and results were proved through theoretical derivation and simulation analysis validation. And this method has significantly improved the range resolution and calibrated the position deviation. Additionally, this algorithm has a strong practicability, due to considering both the indicator and real-time imaging processing algorithm costs.
This paper presents a novel low complexity TOA estimation method for unknown signal under low SNR condition, especially for inner-pulse modulated signal. In this new method, received signal is firstly pre-processed by...
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ISBN:
(纸本)9781785610387
This paper presents a novel low complexity TOA estimation method for unknown signal under low SNR condition, especially for inner-pulse modulated signal. In this new method, received signal is firstly pre-processed by multiplying its delayed conjugation to reduce intra-pulse modulation. Then a refined coherent accumulation is applied to achieve a precise TOA estimation result. Simulation results show that this new method can achieve an accurate TOA estimation for unknown signal under low SNR condition.
GPR for detecting shallow surface target has heavy clutter and target echo cannot be distinguished easily. This paper proposes a PCA-SVD mixed clutter suppression method to realize dimension reduction and reconstructi...
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ISBN:
(纸本)9781849199940
GPR for detecting shallow surface target has heavy clutter and target echo cannot be distinguished easily. This paper proposes a PCA-SVD mixed clutter suppression method to realize dimension reduction and reconstruction, which can improve the performance of clutter suppression effectively. SVD processing remove direct wave, firstly. Then PCA remove uncancelled clutter and remove noise. At last, we design an experiment to validate the performance of clutter suppression.
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 alg...
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ISBN:
(纸本)9781849199940
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 *** scheme is superior to existing technologies, due to its ability to process a continuous-flow input sequence and its prospect for real-time, configurable transform length applications.
Multi-channel phased array radar has the following advantages: detection multiple target, far work distance, antiinterference capability, and sensitive response, etc. The squint SAR (Synthetic Aperture Radar) is an ef...
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ISBN:
(纸本)9781849199940
Multi-channel phased array radar has the following advantages: detection multiple target, far work distance, antiinterference capability, and sensitive response, etc. The squint SAR (Synthetic Aperture Radar) is an effective means of detection in complex background in all-weather and all-day. Multi-channel phased array radar needs the consistency of amplitude and phase. The design of the system parameter should focus on the problem of spatial variability properties of PRF and resolution design. This paper introduces the composition analysis of multi-channel phased array radar, consistency of amplitude and phase, and the design of radar system parameters. The result of flight experimentation verifies the method of system design.
The spectral analysis (SPECAN) algorithm is efficient and always used for synthetic aperture radar (SAR) data processing. But the azimuth dependence of Doppler rate is neglected in SPECAN algorithm, which results in t...
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ISBN:
(纸本)9781785610387
The spectral analysis (SPECAN) algorithm is efficient and always used for synthetic aperture radar (SAR) data processing. But the azimuth dependence of Doppler rate is neglected in SPECAN algorithm, which results in the defocusing of targets away from the scene center. In order to solve this problem, an improved SPECAN algorithm is proposed. Considering the fact that the region of support in the azimuth frequency domain is different for targets in the same range gate, the algorithm equalizes the Doppler rate by nonlinear chirp scaling (NCS) in the azimuth frequency domain. Moreover, a modified map drift (MD) autofocus method is given to estimate the Doppler rate and its dependence. Finally, the effectiveness of the proposed algorithm is verified by real SAR data.
Frequency Modulated Continuous Wave (FM-CW) waveform has been widely used in radar range measuring, speed measuring and imaging. However, the performance of matched filtering for range compression is usually degraded ...
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ISBN:
(纸本)9781785610387
Frequency Modulated Continuous Wave (FM-CW) waveform has been widely used in radar range measuring, speed measuring and imaging. However, the performance of matched filtering for range compression is usually degraded by the nonideal factors in the real radar system, such as the frequency modulation ratio error and the unstable sampling clock. In this paper, an iterative method is proposed to compensate these phase errors induced by the nonideal factors based on the entropy minimum. The principle of the proposed iteration is to construct a series of local quadratic curves to gradually approach the minimum. Finally, both simulated and experimental datasets are used to validate the feasibility and effectiveness of the proposed method.
Aiming at the characteristics of the airborne forwardsquint SAR imaging, a high-performance SAR real-timeprocessing system is established in this paper. Firstly, in order to realize range cell migration correction (R...
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ISBN:
(纸本)9781849199940
Aiming at the characteristics of the airborne forwardsquint SAR imaging, a high-performance SAR real-timeprocessing system is established in this paper. Firstly, in order to realize range cell migration correction (RCMC) accurately and range-azimuth decoupling in forwardsquint SAR imaging, a high-precision SAR imaging algorithm is used in this system, namely nolinear chirp scaling(NCS) algorithm. Secondly, the motion of airborne platform is unstable, so the weighted phase gradient autofocus (WPGA) algorithm is used for motion compensation. Finally, a real-time signal processor is designed which is based on the TMS320C6678 multi-core DSPs issued by TI. The processor satisfied the demands of SAR real-time imaging because of its powerful processing performance and high-speed data transmission ability.
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