Knowledge Base
Quick reference tables for RF and microwave engineering. All content is published for engineering reference only — no component models, specifications or pricing are included. For datasheets and availability, please use our contact channel.
RF & Microwave frequency bands
Common band designations and approximate frequency ranges. Limits vary slightly by convention; treat these as engineering reference points.
| Band | Frequency range | Typical use |
|---|---|---|
| HF | 3 – 30 MHz | Long-range communication, instrumentation |
| VHF | 30 – 300 MHz | Broadcast, line-of-sight links, monitoring |
| UHF | 300 MHz – 1 GHz | Cellular, ISM, monitoring, navigation aid |
| L | 1 – 2 GHz | Satellite links, broadband wireless, GNSS |
| S | 2 – 4 GHz | Point-to-point, weather monitoring, wireless |
| C | 4 – 8 GHz | Satellite, backhaul, test equipment |
| X | 8 – 12 GHz | Backhaul, instrumentation, space-linked payloads |
| Ku | 12 – 18 GHz | Satellite downlink, VSAT, broadband |
| K | 18 – 27 GHz | Satellite, automotive sensing, links |
| Ka | 27 – 40 GHz | High-throughput satellite, 5G mmWave |
| Q / V | 33 – 50 GHz (Q) · 40 – 75 GHz (V) | Backhaul, experimental links |
| E / W / F | 60 – 110 GHz | Millimeter-wave measurement, imaging, links |
S-parameter quick reference
Scattering parameters describe a network at its ports, measured with a vector network analyzer.
Reflection at port 1. Lower magnitude = better match (e.g. < -10 dB).
Transmission from port 1 to port 2. Used for insertion loss and gain.
Transmission from port 2 to port 1. Low value = good isolation.
Reflection at port 2. Same convention as S11.
RF connector selection
Choose by the highest operating frequency and the interface already in your system. Limits are typical upper values for standard grades.
| Connector | Upper frequency | Notes |
|---|---|---|
| BNC | ≈ 4 GHz | Bayonet, common on lab instruments and low-frequency RF. |
| SMA | ≈ 18 GHz | Screw, general-purpose RF and test equipment. |
| N | ≈ 18 GHz | Rugged screw, field and higher-power use. |
| TNC | ≈ 12 GHz | Threaded BNC variant, vibration-resistant. |
| 2.92 mm (K) | ≈ 40 GHz | Precision, shares interface with 3.5 mm / SMA. |
| 2.4 mm | ≈ 50 GHz | Precision mmWave, not mate-compatible with 2.92 mm. |
| 1.85 mm | ≈ 65 GHz | Precision mmWave measurement interfaces. |
| 1.0 mm | ≈ 110 GHz | High-frequency measurement and link use. |
Useful RF calculators
External calculation tools from established RF vendors. Links open in a new tab.
Frequently asked
These are short labels for frequency ranges used across RF and microwave engineering. They help engineers refer to a band without stating exact limits. The table on this page lists common designations and their approximate ranges.
S-parameters describe how a network behaves at its ports. S11 and S22 are return loss (matching); S21 is forward transmission (gain or insertion loss); S12 is reverse isolation. They are measured with a vector network analyzer.
Choose by the highest frequency in your application and the mechanical interface you already use. SMA and N cover up to about 18 GHz; 2.92 mm (K) reaches 40 GHz; 2.4 mm and 1.85 mm extend into mmWave. Match the connector to your cable and instrument interfaces.
No. This knowledge base is reference-only. Component models, specifications and pricing are provided on written inquiry through our contact channel.