  The design of sparse spatially stretched tripole arrays is an important but
also challenging task and this paper proposes for the very first time efficient
solutions to this problem. Unlike for the design of traditional sparse antenna
arrays, the developed approaches optimise both the dipole locations and
orientations. The novelty of the paper consists in formulating these
optimisation problems into a form that can be solved by the proposed
compressive sensing and Bayesian compressive sensing based approaches. The
performance of the developed approaches is validated and it is shown that
accurate approximation of a reference response can be achieved with a 67%
reduction in the number of dipoles required as compared to an equivalent
uniform spatially stretched tripole array, leading to a significant reduction
in the cost associated with the resulting arrays.
