Spectral bias in adaptive beamforming with narrowband interference
IEEE Transactions on Signal Processing
Synthetic aperture radar construction of spectrum map for cognitive radio networking
Proceedings of the 6th International Wireless Communications and Mobile Computing Conference
Phased-MIMO radar: a tradeoff between phased-array and MIMO radars
IEEE Transactions on Signal Processing
| Hi-index | 754.84 |
Radio-astronomical observations are increasingly contaminated by interference, and suppression techniques become essential. A powerful candidate for interference mitigation is adaptive spatial filtering. We study the effect of spatial filtering techniques on radio-astronomical imaging. Current deconvolution procedures, such as CLEAN, are shown to be unsuitable for spatially filtered data, and the necessary corrections are derived. To that end, we reformulate the imaging (deconvolution/calibration) process as a sequential estimation of the locations of astronomical sources. This not only leads to an extended CLEAN algorithm, but also the formulation allows the insertion of other array signal processing techniques for direction finding and gives estimates of the expected image quality and the amount of interference suppression that can be achieved. Finally, a maximum-likelihood (ML) procedure for the imaging is derived, and an approximate ML image formation technique is proposed to overcome the computational burden involved. Some of the effects of the new algorithms are shown in simulated images