The Agilent/Keysight R281A is a waveguide-to-coaxial adapter that converts WR-28 waveguide transmission lines to 50-ohm coaxial lines across the Ka-band frequency spectrum. Designed for bidirectional power transmission, it enables seamless integration between waveguide and coaxial systems in RF and microwave measurement environments.
Technical Specifications
• Frequency Range: 26.5 GHz to 40 GHz
• Waveguide Designator: EIA WR-28 MIL-W-85/3-009
• Flange Designator: UG-599/U MIL-F-3922
• Coaxial Connector: 2.4 mm female
• Maximum SWR (coaxial): 1.13
• Maximum SWR (waveguide band): Less than 1.3
– Key Features
• Low standing wave ratio maintains signal integrity across the full Ka-band
• Bidirectional design supports both transmit and receive applications
• Standard military-specification flanges and connectors ensure interoperability
• Compact form factor integrates into existing test setups without modification
– Typical Applications
• RF and microwave test and measurement systems
• Research and development laboratories
• Manufacturing and qualification testing
• Component characterization requiring mixed transmission media
• System integration where waveguide and coaxial interfaces must interface
– Compatibility & Integration
The R281A mates WR-28 waveguides via UG-599/U flanges to 2.4 mm coaxial connectors. This adapter bridges impedance-matched systems operating from 26.5 GHz to 40 GHz, enabling efficient power transfer and measurement accuracy in Ka-band applications.
