Radiated performance measurements

OTA (OVER THE AIR) OPERATIONS

Characterizing and measuring the quality of reception and the radiated power levels of a mobile device, depending on its position in relation to the transmitter, provides essential data for evaluating the performance of the device. Standardization of these power levels is gradually forming and coming together.

Today, the measurements are carried out according to two similar methods defined in the European standard 3GPP, ETSI TS 134.114 and the American standard CTIA, CTIA OTA V3.

The following two parameters are measured:

  • TRP: Total Radiated Power (dBm)
  • TRS: Total Radiated Sensitivity (dBm)

If the TRP power level measurements are fast and classic, the TRS sensitivity measurements become more complex. The sensitivity can be measured according to several methods (resulting in equivalent results) defined within the standards.

The measurements are carried out in a fully anechoic Faraday cage. The mobile device is positioned on an artificial head. The head is placed on a turntable.

The measurements are made by changing the positions of the device, the antenna and the turntable. These measurements can take a long time and be tedious if the adequate measuring equipment is not available.

LCIE Bureau Veritas provides you with its high-performance and fully automated testing resources, enabling these measurements to be performed on the latest generation mobile devices:

  • Free Space measurements on the following frequency bands: GSM 850, GSM 900, DCS 1800, DCS 1900, WCDMA B1 (2100MHz) and WCDMA B8 (900 MHz) according to 3GPP and CTIA standards.
  • Measurements with SAM (mobile on the right and on the left) on the following frequency bands: GSM 850, GSM 900, DCS 1800, DCS 1900, WCDMA B1 (2100MHz) and WCDMA B8 (900 MHz) according to 3GPP and CTIA standards.
  • Number of measurement points:
  1. – 288 points with Angle Theta (plate) = 15 °, Angle Phi (positioner) = 30 ° and 2 Vertical and Horizontal polarizations.
  2. – 144 points with Angle Theta (plate) = 30 °, Angle Phi (positioner) = 30 ° and 2 Vertical and Horizontal polarizations.
  3. – 96 points with Angle Theta (plate) = 45 °, Angle Phi (positioner) = 30 ° and 2 Vertical and Horizontal polarizations.

The three measurement methods recommended under the standards are feasible.