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Displaying Results 1 - 12 of 12
• ### Computationally efficient two-dimensional direction-of-arrival estimation of electromagnetic sources using the propagator method

Publication Year: 2009, Page(s):437 - 448
Cited by:  Papers (1)
| | PDF (261 KB)

The authors develop a propagator-based algorithm for two-dimensional (2D) direction finding of electromagnetic sources under spatially correlated noise here. The planar-plus-an-isolated array geometry, first defined by Li et al. (1996) is adopted. The authors propose to replace the planar pressure-sensors in Li et al. (1996) by electromagnetic vector sensors, thus exploiting the bene... View full abstract»

• ### ISAR imaging of manoeuvring targets with the range instantaneous chirp rate technique

Publication Year: 2009, Page(s):449 - 460
Cited by:  Papers (1)
| | PDF (829 KB)

The conventional range instantaneous Doppler (RID) algorithm is a well accepted inverse synthetic aperture radar (ISAR) imaging method for manoeuvring targets. In the RID imaging, the cross-range resolution depends on the instantaneous Doppler of scatterers at the imaging instant. For a high manoeuvring target, the instantaneous Doppler of scatterers may be small at some imaging instants and the s... View full abstract»

• ### Azimuth-invariant bistatic multichannel synthetic aperture radar for moving target detection and location

Publication Year: 2009, Page(s):461 - 473
Cited by:  Papers (4)
| | PDF (753 KB)

Ground moving target indication (GMTI) is one of the most important applications of the bistatic synthetic aperture radar (SAR) system as well as the monostatic system. An algorithm for moving target detection and location is presented with an azimuth-invariant bistatic multichannel SAR, which consists of one transmitter (channel) and multireceivers (multichannel). The algorithm is based on the di... View full abstract»

• ### Multibaseline InSAR height estimation through joint covariance matrix fitting

Publication Year: 2009, Page(s):474 - 483
| | PDF (624 KB)

A new joint processing method based on joint covariance matrix fitting is presented for the multibaseline synthetic aperture radar interferometry. This method can make full use of the interferometric information embedded in the joint covariance matrix to estimate the terrain height without eigendecomposition and eigenspace division, and is insensitive to the rank variation of the joint signal subs... View full abstract»

• ### Analysis and extraction of stepped frequency radar signature for micro-motion structure

Publication Year: 2009, Page(s):484 - 492
Cited by:  Papers (2)
| | PDF (596 KB)

Radar signature produced by micro-motion structures contains movement and structure information which is useful for radar target recognition. For stepped frequency (SF) radar, the Doppler modulation is coupled with the stepped carrier frequency. It shifts and smears the high-resolution range profile and makes it difficult to analyse and extract the micro-motion information from the range profile d... View full abstract»

Publication Year: 2009, Page(s):493 - 501
Cited by:  Papers (1)
| | PDF (331 KB)

The problem of adaptive target detection for airborne multi-input multi-output (MIMO) radars with space-time receivers in the presence of Gaussian interference (including clutter and noise) is studied. Previous work has assumed the interference covariance matrix to be known. The case with unknown covariance matrix is investigated here. By exploiting the low rank property of clutter subspace, gener... View full abstract»

• ### Bistatic clutter analysis and range ambiguity resolving for space time adaptive processing

Publication Year: 2009, Page(s):502 - 511
Cited by:  Papers (3)
| | PDF (708 KB)

The clutter characteristics of bistatic airborne radar are more complex than those of monostatic airborne radar. The clutter spectra not only vary severely with range, but also vary with bistatic configuration. The problem of range dependence is more serious in monostatic airborne radar. In this paper, the geometry of arbitrary bistatic airborne radar configuration is firstly analysed, and a formu... View full abstract»

• ### Eliminating ghost images in high-range resolution profiles for stepped-frequency train of linear frequency modulation pulses

Publication Year: 2009, Page(s):512 - 520
Cited by:  Papers (5)
| | PDF (302 KB)

In modern radar systems, using stepped-frequency pulse train is an effective approach to achieve high-range resolution (HRR) with narrow instantaneous bandwidth and low system complexity. However, if the parameters of stepped-frequency (SF) radar (such as single pulse bandwidth, frequency step size and sampling instant) are not prudently designed, ghost image phenomenon (also called range ambigu... View full abstract»

• ### Pitch estimation for non-cooperative maritime targets in ISAR scenarios

Publication Year: 2009, Page(s):521 - 529
Cited by:  Papers (3)
| | PDF (596 KB)

Maritime targets are usually involved in complex motions that complicate the generation of focused inverse synthetic aperture radar (ISAR) images and their scaling in cross-range. By assuming some hypotheses that translate to some restrictions in the maritime surveillance scenario, a signal model for the phase history is derived. This function is calculated here using phase gradient autofocus and ... View full abstract»

• ### New waveform design for magnetron-based marine radar

Publication Year: 2009, Page(s):530 - 540
Cited by:  Papers (1)
| | PDF (1043 KB)

At their long-range mode, conventional magnetron-based marine radar use low pulse repetition frequency (PRF) to extend the unambiguous range, and increase the pulse-width to regain the average power. The proposed new waveform maintains narrow pulses and high PRF even at the long-range mode. Range ambiguity is mitigated by periodic yesno` coding of the transmitted pulse train. Using narrow pulses... View full abstract»

• ### Theory and simulation of ionospheric effects on synthetic aperture radar

Publication Year: 2009, Page(s):541 - 551
Cited by:  Papers (14)
| | PDF (638 KB)

Space-based synthetic aperture radar (SAR) necessarily involves imaging through the ionosphere. At low frequencies (VHF, UHF and L-band) the ionosphere will degrade the SAR image. Previous work has shown that the amount of image degradation strongly depends on the integrated strength of ionospheric turbulence, C k L. The focusing, sidelobes and integrated sidelobe ratio al... View full abstract»

• ### Direction-of-arrival estimation in radar systems: moving window against approximate maximum likelihood estimator

Publication Year: 2009, Page(s):552 - 557
Cited by:  Papers (4)
| | PDF (481 KB)

In this study, we compare two radar target direction-of-arrival (DOA) estimation algorithms: the classical moving window (MW) estimator, implemented in many real radar systems and the approximate maximum likelihood (AML) estimator. The first technique exploits multiple detections in the same time-on-target and the second one exploits the fact that the radar antenna mechanical scanning impresses an... View full abstract»