Optimum use of a 4-element Yagi-Uda Antenna for the Reception of Several UHF TV Channels

Outdoor Yagi-Uda antennas are frequently used in Sri Lanka for the reception of UHF and VHF TV channels. An antenna designed for a particular channel can show poor reception characteristics to other TV channels due to their operating frequencies and physical locations. The first few TV stations, which were set up in nineteen eighties, had VHF transmissions. Those TV channels still operate on VHF, while some of them supplement with UHF transmissions. A large number of TV channels in Sri Lanka use UHF channels for the transmission of their TV programs. The paper studies the dependence of the maximum gain of the antenna, the input power to the dipole of the antenna , and the radiation pattern of the antenna on the operating frequency which are the key indicators of its receiving characteristics. Considering the physical distribution of TV stations in the lowlands of Sri Lanka, this paper searches ways of optimizing reception characteristics of a 4-element Yagi-Uda UHF antenna.