bandpass filter design using ie3d simulator

FR-4 - Wikipedia, the free encyclopedia

thank you sir,

sir i have already gone through that site , i didn't got complete idea about fr4 substrate, just i want to know which material does comes under this group

What do you mean? FR4 is that glassfiber-expoxy material used in standard PCB. This is different from the expensive microwave substrates.

Depending on the manufacturer, the dielectric properties of FR4 can vary. Reported values are somewhere between epsr=4.2 ... 4.9 and the data that I measured for my supplier was 4.7 with tand=0.027. It is difficult to use this material for RF circuits because the dielectric properties are not well controlled. Also, the dielectric loss is higher than typical microwave substrates.