Generalising the co-array, for SAR and MIMO radar

We describe the relationship between far field pattern synthesis for the co-array and the SAR array; showing the application of these to MIMO radar pattern synthesis. Whereas the original co-array concept was developed for planar arrays, the understanding as described in this paper shows its generalisation to arbitrary three dimensional arrays. These ideas are then used to show some useful MIMO radar array configurations. Whilst the analysis applies to the far field we show this also gives a good approximation to the near-field pattern of a focused array, but only in the focal plane.