- Uplink, from user to drone: Generally 2.4 GHz
- Downlink, from drone to user: Generally 5.8 GHz
- These bands are used widely
- We want the noise level to be as low as possible for everyone's usage, so it does not interfere with Wi-Fi signals
- A low noise floor results in a low Signal-to-Noise Ratio, or SNR, for everyone in the area
- We can reduce our transmission power, such as 25 mW for video transmission or 10 mW for the control link
Trade-Offs Between Low and High Frequency
| Characteristics | Low Frequency, 900 MHz and 2.4 GHz | High Frequency, 5.8 GHz |
|---|
| Range | Long | Short |
| Penetration | Good, able to go through trees and walls | Poor |
| Bandwidth | Low, with slower data | High, able to send HD video |
| Spectrum Congestion | Crowded, used by Wi-Fi, Bluetooth, and microwaves | Not as crowded |
| Application | Almost always used for the Control link, or uplink | Used for Video Feed, from Drone to Pilot |
Bandwidth
- A range of frequencies, or the frequency at which the output power drops by half, or the voltage drops by -3 dB
- In the frequency domain, it is the range of frequencies that a signal occupies or a communication channel can support