A new wideband compact slot antenna array
with cavity back for indoor wireless local area network
(WLAN) access points (AP) is described, covering several
wireless communication services from 2.4 to 4.8 GHz, that
is especially designed to enhance multiple-input–multiple-output
(MIMO) system performance. Despite very close
packing of the array elements, these exhibit very low
mutual coupling (<-23 dB) and low cross-polarization (<-14
dB). Each element of the array produces a unidirectional
radiation pattern with a steady gain increase vs frequency
from 5.5 to 8 dBi. Results are confirmed with
measurements.