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In this paper, a method for the design of nonlinear phase, full-band, ultra-wideband (UWB) pulses that satisfy the Federal Communications Commission's effective isotropic radiation power spectrum mask, or more generally, any other given mask, is introduced. The method uses convex programming in each step of the iterative procedure that updates the phase distribution of the goal function. Thanks to its mathematical structure, this method can be easily modified in order to be applied, in sequential fashion, to several different orthogonal UWB pulse-design problems, addressed later in the paper. The first among them is a problem considered in literature-design of multiple pulses, orthogonal when radiated. When employed for solving this problem, the method proposed here produces a considerably larger number of orthogonal pulses with high energy compared to the methods introduced before. As a novelty, the problem of designing pulses which are orthogonal in reception is considered. Then, a modification of our method is presented that can be used to solve this problem. We also introduce statistical criteria of robustness of pulses' orthogonality in reception, to the variation of the pulses' shape caused by the channel transfer function. After that, a modification of the proposed method is presented that is capable of producing a set of pulses with predefined maximum value of this criteria. Furthermore, it is shown that the method proposed can be used to efficiently design orthogonal pulses using a suboptimal value of the sample rate. All the concepts introduced are illustrated by design examples more...

A novel method for suppressing antenna array radiation pattern sidelobes while keeping the main lobe width constant has been proposed. The method is based on the IRLS (iterative reweighted least squares) algorithm, which has found wide application in the field of radar pulse compression. The algorithm is not restricted by the array geometry and the mutual element coupling and has no limitations regarding the array excitation coefficients and array radiation pattern. In comparison with the ECF (envelope constrained filter) method, it showed much better results in sidelobe suppression. The algorithm implementation is simple and straightforward. more...

For original paper by Wang et al., see IEEE Signal Processing Lett., vol.10, p.235-8 (2003 August).

A novel method for the minimax pattern synthesis of FIR filter based wideband beamformers is presented. Emphasis is placed on frequency invariant beamforming, although intentional frequency variant patterns may be synthesised as well. The method is based on the algorithm originally developed for the compressive FIR filter design in pulse compression radars. more...

A novel approach to arbitrary array pattern synthesis is proposed. It is based on the minimax algorithm originally developed for mismatched filter design for radars with pulse compression. The proposed approach allows the user to define the pattern mainlobe beam width and the sidelobe envelope shape. more...