Types of antenna for 2.4GHz and 5GHz data transmission
Classification by device location: – internal – built-in antenna used in tablets, laptops, miniature access points, – external – antenna attached directly to the device or installed at a certain distance and connected with a coaxial cable.
Classification by radiation characteristics: – omnidirectional – radio waves are propagated with the same intensity in all directions on a 360° plane,
Fig. 1. External omnidirectional antenna with vertical polarization
Fig. 2. Internal omnidirectional antenna with vertical polarization
– directional – radio waves are propagated in a single direction (from several to 180°).
Fig. 3. Horn directional antenna
Fig. 4. Micro-band panel directional antenna
Classification by polarization: – vertical – the force lines of the electric field are horizontal, i.e. parallel to the ground, – horizontal – the force lines of the electric field are vertical, i.e. perpendicular to the ground. Two antennas working together must have the same polarization.
The following factors should be considered when selecting the antenna: – Type of antenna (omnidirectional or directional), – polarization (horizontal, vertical), – antenna gain in dBi, – connector type (N, SMA, TNC).