Patent ID: 8018304

Claim:
A filter comprising: at least one first filter, each first filter being a band-reject type filter having a first set of filter parameters that are a function of a first material used to fabricate the respective first filter; at least one second filter, each second filter having a second set of filter parameters that are a function of a second material used to fabricate the respective second filter, each second filter being one of: a band-reject type filter; and a band pass type filter; wherein at least one of the at least one first filter and at least one of the at least one second filter are cascaded together; wherein the first material and the second material are different materials; wherein the filter has a third set of filter parameters that are a function of both the first material and the second material; and wherein the first material has a smaller magnitude temperature coefficient than the second material such that each first filter has less temperature dependent frequency drift than each second filter.