  Sparse arrays can generate a larger aperture than traditional uniform linear
arrays (ULA) and offer enhanced degrees-of-freedom (DOFs) which can be
exploited in both beamforming and direction-of-arrival (DOA) estimation. One
class of sparse arrays is the coprime array, composed of two uniform linear
subarrays which yield an effective difference co-array with higher number of
DOFs. In this work, we present a new coprime array structure termed thinned
coprime array (TCA), which exploits the redundancy in the structure of the
existing coprime array and achieves the same virtual aperture and DOFs as the
conventional coprime array with much fewer number of sensors. An analysis of
the DOFs provided by the new structure in comparison with other sparse arrays
is provided and simulation results for DOA estimation using the compressive
sensing based method are provided.
