I try to reproduce the 700-1000 MHz chebyshev 0.05dB bandpass example described page 42 of Applied Microwave & wireless "transforms aid the design of practical filter".

I can't find the exact structure depicted on fig 7a :

- 23.34nH series L

- 1.61pF series cap

- 11.5pF shunt cap

- 3.13nH series L

- 0.35nH series L

- 1:8.15 trf

I have used shape wizard (bandpass, chebyshev, N=3,R=0.05,fl=700,

fh=1000) followed by extraction (series element first) Inf DC Inf Inf DC DC. This is the only extraction which gives series L1 C1, shunt C2,series L2 but I have shunt L3 series C3 instead of shunt C3, series L3.

How can I proceed ?

Marc

I can't find the exact structure depicted on fig 7a :

- 23.34nH series L

- 1.61pF series cap

- 11.5pF shunt cap

- 3.13nH series L

**- 93.68pF shunt cap**- 0.35nH series L

- 1:8.15 trf

I have used shape wizard (bandpass, chebyshev, N=3,R=0.05,fl=700,

fh=1000) followed by extraction (series element first) Inf DC Inf Inf DC DC. This is the only extraction which gives series L1 C1, shunt C2,series L2 but I have shunt L3 series C3 instead of shunt C3, series L3.

How can I proceed ?

Marc

Shape wizard creates 3DC and 3Inf. 30 dB attenuation is achieved at 409 and 1700MHz. No extraction can provide the topology mentioned in the article.

The "all series resonator" example, instead, uses 1DC and 5 Inf followed by extraction Inf DC Inf Inf Inf Inf. 30 dB attenuation is achieved at 208 and 1429MHz instead. I have used this topology followed by all transforms mentioned (te-pi,...) and found the same result of the article.

I have however a question : At each norton shunt transform, a trf is added. I have moved to the rightmost position at each time and once the design was finished with all the trf at the right I have used remove trf and found the result of the article. Is it the good way to do that ?

Marc