The use of side-mounted loop antennas on platforms to obtain nearly omnidirectional radiation

Antennas mounted to vehicles at VHF frequencies are limited to whip and loop antennas. Often, mechanical constraints force antenna placement to be less than optimal. In this work, we investigate the use of side-mounted loops on rectangular conducting platforms. It will be shown that tall thin platforms radiate similar to a dipole. In addition, as the thickness increases, the loop antennas can radiate in a nearly omnidirectional fashion if the antenna-mounted sides of the platform are not too wide. In effect, a narrow platform width implies return currents for a loop antenna that remain mostly vertical.