Vertically polarized antennas are widely used today because they provide an omnidirectional signal path as opposed to horizontal antennas. Note, however, by using the cross polarization (vertical to horizontal), 30% signal loss will occur.

The feeder or coaxial cable is composed of resistance and reactance, so it will act on the signal propagating along its length. This loss of signal mainly depends on the type of coaxial cable and is defined in each manufacturer’s data sheet. But the rule is: the longer the coaxial cable runs between the transceiver and the antenna, the greater the signal loss.

Isolation refers to separating multiple antennas from each other to avoid the effects of interaction. In some devices, coupling between antennas can reduce their efficiency. Coupling can detune the antenna, causing mismatch losses and reducing efficiency. Isolation is usually expressed in dB, and a good typical isolation should be in the range of 20 to 30 dB or more.