Antennas: power loss on polarization mismatch
Most people in RC hobby knows that receiver and transmitter antennas should match polarization. But what would happen if there was a mismatch? For example when transmitter uses linear vertical and receiver circular left hand? There would be a loss of power, attenuation. How much? Look at table below. Remember: -3dBi means half of power is lost during polarization change and you need +6dBi power (4 times more) to increase range by factor of two.
Vertical | Horizontal | LHCP | RHCP | |
---|---|---|---|---|
Vertcal | 0dBi | -20dBi | -3dBi | -3dBi |
Horizontal | -20dBi | 0dBi | -3dBi | -3dBi |
LHCP | -3dBi | -3dBi | 0dBi | -20dBi |
LHCP | -3dBi | -3dBi | -20dBi | 0dBi |
- -20dBi is practical value. In theory, all power should be lost during this conversion. But we are living in not perfect world and always some power will go though
- Vertical - Linear Vertical Polarization
- Horizontal - Linear Horizontal Polarization
- LHCP - Left Hand Circular Polarized
- RHCP - Right Hand Circular Polarized
I'm Paweł Spychalski and I do things. Mainly software development, FPV drones and amateur cinematography. Here are my YouTube channels: