  In this letter, inspired by the maximum inter-element spacing (IES)
constraint (MISC) criterion, an enhanced MISC-based (EMISC) sparse array (SA)
with high uniform degrees-of-freedom (uDOFs) and low mutual-coupling (MC) is
proposed, analyzed and discussed in detail. For the EMISC SA, an IES set is
first determined by the maximum IES and number of elements. Then, the EMISC SA
is composed of seven uniform linear sub-arrays (ULSAs) derived from an IES set.
An analysis of the uDOFs and weight function shows that, the proposed EMISC SA
outperforms the IMISC SA in terms of uDOF and MC. Simulation results show a
significant advantage of the EMISC SA over other existing SAs.
