Signal Bands
The radio and optical bands used for deep-space communication — S, X, Ka, UHF, and laser.
- S-bandSignal band
A lower-frequency microwave band long used for spacecraft command and low-rate telemetry, and for near-Earth links. Robust and less affected by weather than higher bands, but limited in data rate.
- Frequency
- ≈ 2.0–2.3 GHz
- X-bandSignal band
The workhorse band of deep-space communication and radiometric navigation. Most interplanetary missions send their science data and are tracked on X-band, which balances data rate against antenna size and weather losses.
- Frequency
- ≈ 7.1–8.5 GHz
- Ka-bandSignal band
A higher-frequency band that carries much more data than X-band for the same antenna, at the cost of greater sensitivity to rain and pointing. Increasingly used for high-rate science downlink from deep space.
- Frequency
- ≈ 26–32 GHz
- UHFSignal band
An ultra-high-frequency band used for short-range proximity links — for example between a Mars rover and an orbiter that relays the data to Earth — rather than for direct deep-space communication.
- Frequency
- ≈ 400 MHz
- Optical (Laser)Signal band
Laser communication encodes data on an infrared beam instead of radio waves. Its far shorter wavelength packs data into a tighter beam, promising data rates 10–100× higher than radio — the frontier of deep-space communication, demonstrated by DSOC on the Psyche spacecraft.