Design and simulation of novel broadband antenna for mobile telecommunication

A novel broadband omnidirectional antenna is presented in this paper. The an tenna is proposed for operating at mobile telephone bands. To achieve simple struc ture, the proposed antenna is composed of three monopoles in a plane. The impedance matching and bandwidth for the presented antenna are mainly affected by length and separation of the three monopoles. The theory of basic three monopoles antenna is discussed and simulated. By properly choosing the adequate dimension and adjusting the coupling distance, impedance bandwidth of S
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≪ −10 dB is about 640 MHz, and relative bandwidth is greater than 60 %. The antenna can get omnidi rectional radiation pattern in the whole frequency band. And the main lobe 3 dB width is from 61° to 72.6° in the low frequency without side lobe. The highest gain is stable 4.7 dB. The theory analysis and simulation results are presented.