  The term fractal refers to the fractional dimensions that have recursive
nature and exhibit better array factor properties. In this article, we present
a new class of sparse array where the recursive nature of a fractal can be used
in designing an antenna array called a sparse fractal array by combining
sparsity properties of the various sparse array and the recursive nature of
fractal array. The most important property of the proposed array is the
hole-free difference coarray which makes it a good choice for DOA estimation as
various algorithms like coarray MUSIC etc demand hole-free difference coarray.
But the performance of any array depends on the presence of essential and
nonessential sensors in it which governs whether the difference coarray will
get affected upon sensor failure or not. Hence, in this paper, a rigorous
analysis is done for various combinations of sparse fractal arrays to test
their robustness in presence of a faulty sensor environment.
