Introducing the antenna gain measurement method by the standard antenna method using the radio anechoic box
Application
Evaluating antenna gain usually requires a calibrated standard antenna or anechoic chamber, but it can be simply evaluated using a spectrum analyzer with a tracking generator and a radio anechoic box.
- Obtain the EUT gain by comparing it with the reference antenna (antenna with a known gain).
- As for the measurement environment, the measurement is performed in the anechoic chamber (anechoic box) as in the case of radiation pattern measurement.
- Mainly, dipoles and log periodic antennas are used in the MHz band, and horn antennas are used in the GHz band.
Solution
Measurement procedure
- Set the spectrum analyzer center frequency and span according to the band you want to measure.
- The tracking generator output is measured at the reference antenna end.【Fig.1】
The result is “A (dBm)” - Prepare a receiving antenna and a reference antenna (Tx), and install them in the anechoic box at a certain distance.
- Close the door of the anechoic box and perform the measurement.【Fig.2】
The result is “X (dBm)”. - Take out the reference antenna (Tx) and install the EUT in the same position.
- Close the door of the anechoic box and perform the measurement.【Fig.3】
- If you do not know the maximum radiation direction of the EUT, rotate the turn table and look for the peak gain.
The result is “”Y (dBm)””. - Calculate EIRP EUT (dBm) from the following formula.
EIRP Tx(dBm)=A(dBm)+Gain Tx(dBi)
EIRP EUT(dBm)=Y(dBm)-X(dBm)+EIRP Tx(dBm) - Obtain the EUT gain from the following formula.
Gain EUT(dBi)=EIRP EUT(dBm)-EUT transmit power(dBm)
※EIRP:Equivalent Isotropically Radiated Power
※If the EUT transmission power and gain cannot be separated, such as when the EUT antenna is integrated, EIRP will be the final result.
![](https://micronix-jp.com/english/wp-content/uploads/sites/3/2022/04/Antenna-gain-measurement-by-standard-antenna-method_00.jpg)
![](https://micronix-jp.com/english/wp-content/uploads/sites/3/2022/04/Antenna-gain-measurement-by-standard-antenna-method_01.jpg)
![](https://micronix-jp.com/english/wp-content/uploads/sites/3/2022/04/Antenna-gain-measurement-by-standard-antenna-method_02.jpg)
System configuration
Anechoic box (With manual or electric turntable) |
Antenna (standard and reception) |
Spectrum analyzer (With tracking generator) |
Others, cable stands and various options |
Products introduction
Electromagnetic anechoic box / Shield box
Spectrum analyzer (With tracking generator)
![](https://micronix-jp.com/wp-content/uploads/2022/11/contact_cta_cover.png)
Please feel free to contact us.
If you want to verify 5G, customize a radio wave shield box, or need product repair, please do not hesitate to contact us about any small matter.