1. Working frequency band

The antenna always works in a certain frequency range (bandwidth), which depends on the requirements of the index. The frequency range meet the index requirements is the working frequency of the antenna. Various wireless systems are different, and the frequency band used by operators is also different. It is necessary to select the antenna of the appropriate frequency band.

2. Polarization mode

Antenna polarization refers to the direction of electric field intensity formed when the antenna radiates. When the electric field intensity direction is perpendicular to the ground, the electric wave is called vertically polarized wave; When the electric field intensity direction is parallel to the ground, the electric wave is called horizontally polarized wave.

3. Impedance

For a wire antenna, the ratio of the voltage and current at the input of the antenna is called the input impedance of the antenna. For the area antenna, the voltage standing wave ratio on the feeder is often used to represent the impedance characteristics of the antenna.Select the appropriate feeder and impedance matcher to ensure that the input impedance of the antenna matches the characteristic impedance of the feeder, so as to maximize the power input to or output from the antenna.

4. Directivity of antenna

The directivity of an antenna refers to the ability of the antenna to radiate electromagnetic wave in a certain direction. For the receiving antenna, directivity indicates the receiving ability of the antenna to the radio waves transmitted from different directions. The directional characteristic curve of antenna is usually represented by a directional pattern.

5. Lobe width (also known as beam width or main lobe width or half-power angle)

Lobe width refers to the included angle between two points where the radiation intensity is reduced by 3 dB (power density is reduced by half) on both sides of the maximum radiation direction of the main lobe. The narrower the lobe width, the better the directivity, the farther the action distance, and the stronger the anti-interference ability.

6. Front to back ratio

Anterior posterior ratio refers to the ratio of the maximum value of the main valve to the maximum value of the back valve. It shows that the antenna can suppress the back lobe.

7. Antenna Gain

Antenna gain refers to the ratio of the power density of the signal generated by the actual antenna and the ideal radiation unit at the same point in space under the condition of equal input power. The gain is closely related to the antenna pattern. The narrower the main lobe is, the smaller the side lobe is, and the higher the gain is. Antenna gain is used to measure the ability of an antenna to radiate electromagnetic waves in a specific direction. It should be noted that the antenna itself does not increase the energy of the radiated signal. It only concentrates the energy in a certain direction through the combination of antenna oscillators and changing its feeding mode.

8. Inclination

The inclination of the antenna refers to the inclination of the radio wave, not the mechanical inclination of the antenna oscillator itself. The inclination angle reflects which height angle the antenna receives the strongest radio wave.

9. Isolation

The isolation degree of an antenna refers to the uncorrelation of two antennas or one dual polarization antenna. The qualified isolation degree parameter ensures the diverse reception performance of antennas in the same sector.

10. Standing wave ratio

The antenna standing wave ratio is an indicator of the matching degree between the antenna feeder and the base station. It is generated because the incident wave energy is not fully radiated after being transmitted to the antenna input, resulting in reflected waves and superposition.