A new quasi-omnidirectional vertical polarisation antenna with low profile and high gain for DTV on vehicle

A new quasi-omnidirectional vertical polarisation antenna with low profile and high gain is presented. With the symmetric folded dipole and ground mirror, the antenna exhibits almost omi- nidirectional radiation performance and the measured gain exceeds 10 dB, its available bandwidth is enough for digital TV in Beijing, which will even be able to compensate the depolarisation. The relationship between the antenna size and gain is investigated. By optimisation, the size of antenna can be reduced and maximum gain achieved.