Conceptual ID for 300MHz bandpass filter design

[elberlee]

Dear,

I want to design a high Q BPF at 350 MHz, actually, only 350 MHz is important, so I want to the pass band as narrow as possible, the BW less than 10MHz will be very good.

At the same time, the insertion loss should also be controlled as low as possible, less than 1dB will be very helpful.

Can anyone give me some suggestion about the prototype of the filter? lump component ? Distribute component? anything ....

Thank you in advance!

 

[biff44]

A saw filter will probably do the best job:

https://www.oscilent.com/catalog/Category/if_filters_300m0.html

if not, get some long λ/4 ceramic resonators, and make a multipole banpass filter:

 

[elberlee]

A saw filter will probably do the best job:

https://www.oscilent.com/catalog/Category/if_filters_300m0.html

if not, get some long λ/4 ceramic resonators, and make a multipole banpass filter:

the coaxial ceramic resonator is a good choice, thank you very much!
With the ceramic resonator, the harmonics need to be removed by additional LPF or BPF. Do you think the distribute components could give a better insertion loss than the lumped component at this frequency range? (300MHz to 1 GHz)

Thanks,

 

[BigBoss]

Helical resonators with EM couplings will give you better insetion loss and narrower bandwidth compare to lumped filters.
They are also cheaper than coaxial ceramic resonators.
It's very common in CATV networks ( BW=5-10MHz)