FPV Antenna Guide, RHCP, LHCP Polarisation, Directional vs Omnidirectional

FPV Antenna Guide, RHCP, LHCP Polarisation, Directional vs Omnidirectional

Antennas are a crucial component in your FPV system, affecting both the range and quality of your signal. This guide explains the different types of antennas used in FPV (First Person View) flying, helping you choose the right one based on your needs.

Antenna Frequency

FPV antennas are frequency-specific, meaning you must match the antenna frequency to your FPV equipment. Most FPV systems use 5.8GHz antennas, which are smaller than lower frequency antennas like 2.4GHz.

Antenna Polarization: Linear vs. Circular

Polarization is how the signal is transmitted and received by the antenna. There are two main types:

  • Linear Polarization: Signals are transmitted in a straight line. These can provide longer range but require perfect alignment between the transmitting and receiving antennas. They’re less ideal for drones due to constant movement.
  • Circular Polarization: Signals rotate in a corkscrew pattern, making them more reliable for drones as they maintain consistent overlap regardless of the drone’s orientation. Most FPV pilots prefer circular polarized antennas for this reason.

LHCP vs. RHCP: Circular polarized antennas come in left-hand (LHCP) and right-hand (RHCP) versions, and both antennas (transmitter and receiver) must be of the same type for compatibility.

Directional vs. Omnidirectional Antennas

Antennas are also categorized by how they direct their signal:

  • Omnidirectional Antennas: These offer wide coverage with shorter range, ideal for general FPV flying as they don’t need to be pointed directly at the aircraft.
  • Directional Antennas: These provide longer range but have a narrow signal beam, requiring the antenna to be pointed at the drone. Ideal for long-distance flights but may need manual or automated tracking.

Using Multiple Antennas

For optimal performance, some FPV systems use a combination of antennas. A common setup is using an omnidirectional antenna for general coverage and a directional antenna for extended range. These setups use diversity receivers to automatically switch between antennas for the best signal.

Antenna Gain

Gain refers to the antenna's ability to focus its signal, measured in decibels (dB). Higher gain antennas stretch the signal for longer range in a specific direction, at the cost of beam width. Lower gain antennas provide a more even, spherical coverage.

Common FPV Antennas

  • Duck Antennas: Linear, omnidirectional, with moderate gain.
  • Cloverleaf and Skew Planar: Circular, omnidirectional, popular for general FPV use.
  • Helical and Patch Antennas: Directional, offering longer range in a specific direction.

To learn more check out our full article over on dronetrest.com - The complete guide to FPV antennas for your drone