Frequency-Hopping Code Design for MIMO Radar Estimation Using Sparse Modeling

Mathematical Problems in Engineering

Cheng

et al. 2017

RCI is a novel superresolution staring imaging technique based on the idea of wavefront modulation and temporal-spatial stochastic radiation field. For RCI, the reference matrix should be known accurately, and the imaging performance depends on the incoherence property of the reference matrix. Unfortunately, the modeling error, which degrades the performance significantly, exists generally. In this paper, RCI using frequency-hopping waveforms (FH-RCI) is considered, and a FH code design method aiming to increase the robustness of RCI to modeling error is proposed. First, we derive the upper bound of imaging error for RCI with modeling error and conclude that the condition number of the reference matrix determines the imaging performance. Then the object function for waveform design which minimizes the condition number of the reference matrix is achieved, and the quantum simulated annealing (QSA) is employed to optimize the FH code. Numerical simulations show that the optimized FH code could decrease the condition number of the reference matrix and improve the imaging performance of RCI with modeling error.

Section: Mathematical Problems In Engineeringmentioning

confidence: 99%

Section: Mathematical Problems In Engineeringmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Waveform Analysis and Optimization for Radar Coincidence Imaging with Modeling Error

Zhou

Mathematical Problems in Engineering

Cheng

et al. 2017

“…Significantly increased DOFs can be obtained by exploiting these independent paths. In [82], [83], it is shown that frequency-hopping codes can be utilized for MIMO radar waveform diversity design. Nevertheless, since orthogonality is only approximated in practice, waveform diversity design is still a technical challenge.…”

Section: Introductionmentioning

confidence: 99%

An Overview on Time/Frequency Modulated Array Processing

IEEE J. Sel. Top. Signal Process.

Farina³

2017

192

Time and frequency modulated arrays have numerous application areas including radar, navigation and communications. Specifically, a time modulated array can create a beampattern with low sidelobes via connecting and disconnecting the antenna elements from the feed network, while the frequency modulated frequency diverse array produces a range-dependent pattern. In this paper, we aim to introduce these advanced arrays to the signal processing community so that more investigations in terms of theory, methods and applications, can be facilitated. The research progress of time/frequency modulated array studies is reviewed and the most recent advances are discussed. Moreover, potential applications in radar and communications are presented, along with their technical challenges, especially in signal processing aspects.Index Terms-Time modulated array, frequency modulated array, frequency diverse array, array signal processing, phasedarray, range-dependent beamforming, multiple-input multipleoutput (MIMO) radar.

“…These characteristics contrast with the range-independent transmit beampattern in a phase-array radar. FDA radar is different from orthogonal frequency division multiplexing (OFDM) radar [8] and multiple-input multiple-output (MIMO) radar [9,10]. OFDM radar uses orthogonal subcarriers, but nonorthogonal carriers are employed in FDA radar.…”

Section: Introductionmentioning

confidence: 99%

Range-azimuth decouple beamforming for frequency diverse array with Costas-sequence modulated frequency offsets

EURASIP J. Adv. Signal Process.

Shao

2016

Different from the phased-array using the same carrier frequency for each transmit element, the frequency diverse array (FDA) uses a small frequency offset across the array elements to produce range-angle-dependent transmit beampattern. FDA radar provides new application capabilities and potentials due to its range-dependent transmit array beampattern, but the FDA using linearly increasing frequency offsets will produce a range and angle coupled transmit beampattern. In order to decouple the range-azimuth beampattern for FDA radar, this paper proposes a uniform linear array (ULA) FDA using Costas-sequence modulated frequency offsets to produce random-like energy distribution in the transmit beampattern and thumbtack transmit-receive beampattern. In doing so, the range and angle of targets can be unambiguously estimated through matched filtering and subspace decomposition algorithms in the receiver signal processor. Moreover, random-like energy distributed beampattern can also be utilized for low probability of intercept (LPI) radar applications. Numerical results show that the proposed scheme outperforms the standard FDA in focusing the transmit energy, especially in the range dimension.