Matlab Software-based Dual-band Array Antenna Design

Dual band, wide band and wide scan angle phased arrays is studied in this thesis.For the arrays unit, the method of fed, wideband, miniaturization, and muti-frquency, and wide beamwidth and the basic technology and analysis method of microstrip patch antennas is discussed. Based on the method, we design and simulate a wide band and wide beamwidth microstrip antenna and a dual band, wide band, wide beamwidth microstrip antenna. By adding a iron box outside the E patch antenna, which can reducing the radiation area, we get an antenna that works at the frequency band form 1200MHz to 1400MHz and its half-power beamwidth is±60 degree between this band. Also, by comprising two printed dipole and designing suitable feed network, we get an antenna works between 400MHz-480MHz and 1200MHz-1400MHz and its half-power beamwidth is also±60 degree between this two bands.Then, after introducing some basic theory and simple characteristics of phased arrays, we first introduce the Invasive Weed Optimization (IWO) into the synthesis of non-uniformly phased array and get a dual band, wide band and wide scan angle phased arrays. The phased arrays can steer to±60degree at 400MHz-480MHz and 1200MHz-1400MHz and no grating lobe appear in the real space. However, the active reflection coefficient (ARC) of the arrays unit is big, most of the energy is reflecting to the feed port.For the active element pattern (AEP) and active reflection coefficient (ARC), we try to reduce the couple between the units by changing the shape of the antenna to increase the scan angle. A single printed dipole with two parasitic monopole elements to broaden the E-plane radiation pattern to±60 degree is designed. Designing a uniform array with this unit, the arrays can steer to±40 degree while the ARC is small than -10dB which is wide than normal dipole arrays.