Wideband Active and Passive Antenna Solutions for Handheld Terminals
A printed dipole antenna with integrated balun is presented. The radiating structure is a two element dipole with resonances at 900 and 1700 MHz, with the balun providing one extra resonance at each band. By co designing the radiating element with a Marchand balun modified for dual band operation, an antenna covering the cellular bands 824 960 and 1710 2170 MHz has been achieved. Measurements on a fabricated antenna on low cost FR 4 substrate show antenna efficiencies of 80 and 70% in the lower and upper band respectively. Despite the use of a dual element radiator, the radiation pattern that is close to omni directional H plane is obtained.