What is the difference between WR designations and the corresponding frequency ranges?
Standard Waveguide Band Reference
The standard WR waveguide series provides a complete set of waveguide sizes covering frequencies from below 1 GHz to above 300 GHz. Each waveguide size is optimized for a specific frequency band with approximately 40% bandwidth. The WR number directly encodes the physical dimension: WR-90 has a broad wall dimension of 0.900 inches (22.86 mm).
| Parameter | Standard Rect. | Ridged | Circular |
|---|---|---|---|
| Single-Mode BW | 40% (1.25-1.9 fc) | 50-150% | 26% (1.31:1 ratio) |
| Attenuation | Low | Moderate (3-5x) | Low to very low |
| Power Handling | High (kW-class) | Moderate | High |
| Polarization | Single | Single | Dual (TE11) |
| Cost | Low (commodity) | Medium | High (specialty) |
Frequently Asked Questions
What are the most commonly used sizes?
WR-90 (X-band): radar, satellite communications. WR-42 (K-band): satellite uplinks, 5G backhaul. WR-28 (Ka-band): satellite earth stations. WR-10 (W-band): automotive radar, point-to-point links, scientific research. These sizes account for the majority of waveguide component sales.
What about reduced-height waveguide?
Reduced-height (half-height) waveguide uses the same broad dimension (a) but half the narrow dimension (b). This provides the same frequency range in a lower profile but with higher attenuation and reduced power handling. It is used in space-constrained applications.
Can I convert WR designations to metric?
Yes. Multiply the WR number by 0.254 to get the broad dimension in mm. WR-90: 0.90 × 25.4 = 22.86 mm. WR-10: 0.10 × 25.4 = 2.54 mm. International standards use metric (R) or IEC designations instead of WR.