rf tunable filter vendors?
Hittite has tunable LPF from DC-7.6G. What do you need, BPF or LPF?
PS: Sorry, the LPF cutoff freq is above 2G, maybe that is not fit for you.
is 600MHz your operating freq or the bandwidth you require ?
if 600MHz is the operating freq, then Toyo make a wide range of tunable Helical Resonators hi, lo and band pass filters. Covering at least 100 to 1300MHz. Have used them often in projects I have built over the years
Dave
Dave, 600MHz is the working frequency. Did you mean Toko? Their helical filter is mechanic tunable, not electronically tunable.
Tony, I'm looking for BP filter. thanks for refered Hittite. Hittite tunable filter covers band higher than 1GHz. It's not in my band , but it gives me an idea of what the current technology is. I'm surprised the minimum band width is 11%. Is 1% band width and step possible?
You would need components with very high Q factor, which makes the filter really big and really expensive. At microwave frequencies, there are tunable narrow band filters with YIG resonators, but these are not available for 600MHz.
If you are at an early design stage, you might think about a different system architecture that avoids this difficult filter spec. If it's too late now: What are the filter specification that you really need?
Thnaks Volker for your input.
In the prototype I had mask issue which led me to the filter approachs, fixed or tunable. All types of filter solution returned answer No, except cavity filters. Major concers are fc accuracy and temperature stability.
There is chance for different system design and I did think about other system architectures like 2 stage IF, but still the 2nd mixer spurious and PA(class A 1W) unwanted emission are hard to meet mask-- -80dBc for 2nd alternate channel.
