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In the scene of ground moving target detection, the target echo information is often corrupted by strong clutter. In this letter, a joint clutter suppression algorithm is proposed based on robust principal component analysis and total variation denoising for pulse Doppler radar. The novel method named total variation‐ robust principal component analysis replaces the l1‐norm in robust principal component analysis algorithm with a total variation seminorm. Total variation robust principal component analysis retains the clutter suppression ability of robust principal component analysis, and effectively separates the target from the noise in range‐Doppler domain. [ABSTRACT FROM AUTHOR]

This letter considers the coherent integration and detection for hypersonic target in the first‐order approximate (FOA) echo model. The proposed algorithm first accomplishes the modified pulse compression utilising the designed reference signal, then conducts the Keystone transform (KT) based coherent integration method to detect the target. Compared with the existing methods which model the received signal without considering the target's intrapulse motion, the proposed method has a lower modeling error and can maintain good noise robustness for weak hypersonic target detection. Experimental results are given to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Range ambiguity suppression is a significant problem in traditional pulse‐Doppler radar systems, especially when the pulse repetition frequency is set high to avoid Doppler ambiguity. One possible way to deal with such problem is to apply the noise radar system, by transmitting pulse‐agile waveforms and using a group of matched filters as the receiver to accumulate the power of unambiguous echoes while dispersing the range‐ambiguous ones. However, when strong targets or heavy clutters exist, the dispersed ambiguous power is still high, which leads to high range‐Doppler sidelobes and overwhelms the weak targets. This paper explores a new way to deal with the range‐ambiguity suppression problem in noise radar. The range‐ambiguity suppression as a sparse recovery problem is formulated, and then both the unambiguous and ambiguous targets (and/or clutters) can be simultaneously reconstructed. The proposed method can enhance the range‐ambiguity suppression performance and synthetic an ambiguity‐free range‐Doppler map with a low sidelobe level, which ensures the weak target recovery performance even in a cluttered environment. [ABSTRACT FROM AUTHOR]

This paper presents an algorithm to enhance the range‐Doppler imaging performance for noise radar. Traditional matched filtering based method suffers from high range and Doppler sidelobes, which makes the weak targets overwhelmed by the sidelobes of strong targets or clutters in the range‐Doppler map. Sparse recovery based methods have been widely used to suppress such sidelobes, but most of them assume a repetitive transmit waveform, which cannot be applied to noise radar applications. In this letter, the range‐Doppler imaging problem for noise radar is formulated as a sparse recovery model and solved by a 2D generalized smoothed‐l0 algorithm. The proposed method can deal with the random waveforms varying among different pulses in noise radar. The robustness of the proposed method in strong noise and clutters is validated by simulation results. [ABSTRACT FROM AUTHOR]

An iterative adaptive approach (IAA) based algorithm is presented to realise coherent integration for the random pulse repetition interval radar. The proposed method firstly removes the effect of Doppler ambiguity via phase compensation, and then accomplishes target focusing via conducting the azimuth IAA and range inverse fast Fourier transform. Theoretical analysis and numerical experiments have verified the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Wide‐band interference (WBI) can severely degrade synthetic aperture radar image quality. This Letter proposes a new WBI suppression technique using time‐varying filtering method and sparse recovery. In this method, a time‐varying filter is firstly set up in the short‐time Fourier transform domain as a pre‐processing step to suppress the major power of WBI, and then, an adaptive dictionary‐based sparse recovery algorithm is developed to recover the useful target echo loss resulting from time‐varying filtering. Finally, traditional SAR imaging algorithms can be performed to obtain a well‐focused image. Simulation results demonstrate the validity of the proposed method. [ABSTRACT FROM AUTHOR]

A new method for three‐dimensional (3D) imaging via a narrowband bistatic multiple‐input–multiple‐output (MIMO) radar with two uniform rectangular arrays is presented. After matched filtering and phase compensation, the method utilises the 2D cross‐range images measured by the transmit and receive arrays to reconstruct the 3D image of the target. Compared with the 3D wideband monostatic MIMO imaging, lower hardware cost can be achieved since the narrowband waveforms are employed. In addition, the range alignment in wideband imaging can be avoided for the poor range resolution of the narrowband waveforms. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) gold multiple signal classification (gold‐MUSIC) is proposed in order to reduce the complexity of MUSIC and make real‐time processing possible for joint range and angle estimation by multi‐carrier frequency multiple‐input multiple‐output radar. 2D gold‐MUSIC evaluates the MUSIC spectrum at coarse intervals, then determines peaks by narrowing the 2D search area iteratively based on a simultaneous gold‐section of range and angle to find accurate localisation of the peaks. The proposed method eliminates huge computation burden caused by a grid‐by‐grid spectral search of classical MUSIC and obtains remarkable resolution in range and angle with no dependence on array configurations. Numerical studies demonstrate the effectiveness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

In general, ionosphere phase contamination can expand the Bragg peak of sea clutter and the echo signal from a target in sky‐wave over‐the‐horizon radar (OTHR). By exploiting the subspace algorithm, an effective approach of ionosphere phase decontamination is proposed to solve the above‐mentioned problems. In this new scheme, the stronger one of two spreading Bragg peaks is extracted by an adaptive sliding‐window bandpass filter, and the instantaneous phase of the spreading Bragg peak is obtained by the subspace algorithm. Both the theoretical analysis and the experimental results of the real OTHR data have confirmed the feasibility of this new method. [ABSTRACT FROM AUTHOR]