Abstract:
A small, wideband, multiple-input-multiple-output antenna
is presented for 4G long term evolution (LTE) applications. The proposed
antenna consists of a vertically polarized wideband stepped slot,
as well as a horizontally polarized narrowband, uniform slot, integrated
on a single substrate and fed by two ports. A prototype of the proposed
antenna was designed, fabricated, and measured. The stepped slot antenna
achieves an enhanced bandwidth of 122% from 0.77 GHz to
3.12 GHz, covering the 2G, 3G, and 4G bands. The narrowband slot
achieves a bandwidth of 35% from 2.11 GHz to 3.01 GHz, covering the
4G band frequencies only. The isolation between the two slots is greater
than 21 dB over the entire band of interest. The radiation pattern of the
wideband slot in the horizontal plane is omnidirectional in nature while
the narrowband slot exhibits a bidirectional radiation pattern in the horizontal
plane. The proposed antenna is suitable for indoor, ceilingmount,
microcell 4G LTE applications.