The MIMO communication system has been one of the most promising technologies, well suited for high data rate communication. A MIMO (Multiple-Input-Multiple-Output) system use at least two antenna structures and is more advantageous than single-input single-output (SISO) in an aspect of increasing channel capacity and reducing transmitting power. MIMO antennas should have compact structure, high radiation efficiency, low envelope correlation, and high isolation between the signal ports. In small structures (antennas spaced closely), the application of MIMO technology has been restricted by high degree of coupling and spatial correlation between antenna elements due to the limited available space. The isolation between antennas become critical as it can deteriorate the system performance and decreases channel capacity. The Ultima MA530 MIMO antenna is low profile, heavy-duty, fully IP67 waterproof external M2M antenna for use, transportation and remote monitoring applications. This unique omnidirectional antenna provide high efficiency and high isolation between antennas elements in a heavy-duty low profile compact structure, delivering powerful MIMO antenna technology for Wi-Fi 802.11n and emerging 802.11ac. The antenna screws down permanently onto a roof or metal panel and can be pole or wall-mounted. One antenna elements is vertically polarized and one is horizontally polarized to increase the isolation between antennas.