I have a problem on broaden all bandwidth (880-960MHz, 1710-1880MHz, 1850-1990MHz, 1920-2170MHz). I use stack method, where i have 4 patches calculate base on fc=c/4(L+W) formula, then i stack them 1 by 1 like staircase with shorting plate in btw. as a result i get 3 bands. however all those band are not wide enough to cover the service frequency in market.
Hi Poey,
You might want to tune the antenna to a lower impedance than 50 ohm, get a "small circle" on the Smith Chart, which you can than move to the 50 ohm with a simple matching circuit. It will probably work for only on frequency, unless if you are using multiple feeds for different frequencies.