Microwave Frequency Bands
Understanding Microwave Bands
The letter-band designations are used throughout the RF industry despite their arbitrary origins. Understanding the characteristics and applications of each band is fundamental to RF engineering.
IEEE Microwave Band Designations
| Band | Frequency | Key Applications |
|---|---|---|
| L | 1-2 GHz | GPS, ATC radar, mobile satellite |
| S | 2-4 GHz | Weather radar, 5G sub-6, Wi-Fi |
| C | 4-8 GHz | Satellite (C-band), weather radar |
| X | 8-12 GHz | Military radar, satellite |
| Ku | 12-18 GHz | Satellite TV (DBS), radar |
| Ka | 27-40 GHz | Satellite broadband, 5G |
| W | 75-110 GHz | Automotive radar, backhaul |
Frequently Asked Questions
What are the microwave frequency bands?
Letter designations from WWII: L (1-2), S (2-4), C (4-8), X (8-12), Ku (12-18), K (18-27), Ka (27-40), V (40-75), W (75-110 GHz). Each has characteristic applications and properties.
Why were letters used?
The letter designations originated in WWII for security. The frequencies of radar systems were classified, so letter codes were used instead. The designations persisted and are now standard industry terminology.
Which band is most important commercially?
S-band and sub-6 GHz dominate cellular (5G NR FR1). Ku-band dominates satellite TV. Ka-band is growing for satellite broadband. W-band is growing for automotive radar. Each band serves different market needs.