Flann has developed a new range of double ridge multihole coupler for standard double ridge waveguide sizes and tailored to any special bandwidth requirements.

Our unique design of the coupler array combined with precision machining practice provides better than 40 dB directivity full band with typical directivities better than 45 dB achieved.

Flann is now able to provide a service to make any standard or non-standard type of coupler within the constraints of commercial viability.

We are now able to offer the industry’s only 40 dB directivity coupler with a full band coupling flatness of less than +/-1 dB.

All double ridge couplers are available in nominal coupling values from 10 dB to 50 dB.


  • Directivity > 40 dB – a new industry standard
  • Flat Coupling Response
  • Models up to 40 GHz
  • Coupling values from 10 dB to 50 dB
Double ridge multihole coupler | WRD131
ModelWG SizeMin. Directivity dBNominal Coupling AccuracyCoupling Sensitivity ± dBPrimary Arm VSWRSecondary Arm VSWR
WRD2001312.0 - 4.8WRD200D24350.811.061.35
WRD3501313.5 - 8.2WRD350D24350.811.061.35
WRD4751314.75 - 11.0WRD475D24350.811.061.35
WRD5801315.8 - 16.0WRD580D28350.811.061.35
WRD6501316.5 - 18.0WRD650D28350.811.061.35
WRD7501317.5 - 18.0WRD750D24350.811.061.35
WRD11013111.0 - 26.5WRD110C24320.811.11.35
WRD18013118.0 - 40.0WRD180C24320.811.11.35