Digital Average Power Measurement Description

Last updated: November 27, 2008

How is a Digital Average Power Measurement Made?

Digital average power measurements are broadband power measurements made directly on the RF input (the signal is not downconverted in frequency, see Block Diagram ). The input waveform is detected by a true average power detector. The test set's digital signal processor (DSP) then determines the average power of the signal over a 10 ms measurement period (6 slots).

The measurement triggers on the test set's internal ~1.667 ms slot clock. The result is reported in dBm.

The digital average power measurement has a bandwidth of approximately 4 GHZ. For this reason, significant signal energy outside the 1.23 MHz access terminal transmit bandwidth will increase the measured value.

Digital Average Power Measurement Parameters

Multi-Measurement Count - (See Statistical Measurement Results ).
Trigger Arm - (see Trigger Arm (Single or Continuous) Description ).
Timeout Time/State - (see Measurement Timeouts ).

Digital Average Power Measurement Results

Integrity Indicator - (see Integrity Indicator ).
Digital Average Power (in dBm).
The Expected Terminal Power (see Expected Power ) is also displayed on the measurement screen when either of the following conditions is met:
- Current physical layer subtype is Subtype 0 (see Release A Physical Layer Subtype ), the receiver power control is set to auto and Test Application Protocol is set to RTAP.
- Current physical layer subtype is Subtype 2 (see Release A Physical Layer Subtype ), the receiver power control is set to auto and Enhanced Test Application Protocol is set to RETAP.
Or the Expected Terminal Total Power (see Expected Power ) is displayed on the measurement screen when the following condition is met:
- Current physical layer subtype is Subtype 3 (see Release B Physical Layer Subtype ), the receiver power control is set to auto, the Multi-carrier Test Application Protocol is set to RMCTAP and the Connected Carriers is more than one.

An example measurement result display (for subtype 0 physical layer) is shown below:

Digital Average Power Input Signal Requirements

Input Signal Requirements

Key C.S0033 Tests Performed using the Digital Average Power Measurement

4.3.4 Maximum RF Output Power

Calibrating the Digital Average Power Measurement

Refer to Calibrating the Test Set for a description of digital average power calibration.