Experimental investigation of broad-band microstrip antennas

An experimental investigation of broadband microstrip antennas on a PTFE substrate with permittivity epsilon /sub r/=2.1 and thickness h=1.6 mm is presented. A 17% bandwidth improvement is achieved by modifying the feed on the substrate with coaxial-fed disk antennas. Experiments carried out on circularly shaped modified patches showed a further bandwidth improvement of 80% over conventional microstrip patches. This method of bandwidth improvement is based on the fact that the impedance match is the limiting factor to the bandwidth for this class of antennas.<
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