Interdigital Bandpass Filter
FEATURES:
•Low Insertion Loss
•Low VSWR
•Flat Frequency Response
•2% TO 40% BANDWIDTH
Description
| MODEL NUMBER |
FREQUENCY RANGE (GHz) |
3dB* BANDWIDTH % OF F.C. |
NUMBERS OF* SECTIONS |
VSWR OVER* BANDWIDTH |
RANGE* Deg. |
| FI | 1 To 18 | 2% To 40% | 4 To 15 | 1.50:1 To 12.4 | 0 C To +50 C |
* Custom Design Available. Contact Manufacturer For Other Specifications *
GENERAL SPECIFICATIONS:
Impedance : 50 Ohms
Power Handling : 50 WATTS
The Maximum Insertion loss at a center frequency can be determined using the following formula :
Insertion Loss = (K) (0.5 + No. of Sections) + 0.1 / 3 db Bandwidth
Where the insertion loss constant (K) = 0.85 Up to 18.0 GHz Example : Center Frequency = 8000 MHz,
3 db BandWidth = 1700 MHz
Number of Sections = 8
The db BandWidth = (100 (1700) / 8000 = 21.25%
Therefore Insertion Loss = (0.85) (0.5 + 8) + 0.1 / 21.25 = 0.44db
The Attenuation Range can be determined using the following formula :Attenuation Range = 3 db BW @ Fc = Reject Freq. – Fc / 3dbBandWidth
Example : Center Frequency = 8000 MHz, 3 db BandWidth = 1700 MHz
Number of Sections = 7
To find the Attenuation at 5900 and 9000 MHz :
The 3 db BandWidth from the Fc = 5800 – 8000 / 1700 = 1.294
The 3 db BandWidth from the Fc = 10200 – 580 / 1700 = +1.294
VSWR Bandwidth : Refer to Graph 3
ORDERING INSTRUCTIONS
FI-XXXXX-XXXX-XX-XX
Combline InterDigital—–FI-
Center Frequency (Fc)——XXXXX-
Minimum 3 db Bandwidth————–XXXX-
Number of Sections—————————-XX-
Input Connector————————————–X
Output Connector—————————————-X
MECHANICAL OUTLINE: Consult Manufacturer For Specific Configurations and Mounting Hole Locations
