Spectrum Analyzer Measurements : Channel Power
 
Channel Power
Channel power measurements are set up using the SETUP Menu (Channel Power). The Channel Power measurement is one of most common measurements for a radio transmitter. This test measures the output power, or channel power, of a transmitter over the frequency range. Out‑of‑specification power measurements indicate system faults, which can be in the power amplifiers or in filter circuits. Channel Power measurements can be used to validate transmitter performance, comply with government regulations, or to keep overall system interference at a minimum.
Channel Power Measurement
1. Channel power measurement results are shown in a table at the bottom of the display.
2. Dashed vertical lines and a shaded region define the main channel.
3. All channel power measurement parameters are set via the SETUP menu.
Frequency and span settings for many signal standards can be set as follows:
1. Press MEASURE on the main menu.
2. Select Channel Power from the MEASUREMENT button.
3. Press SETUP and then do the following:
• Set the channel INTEGRATION Bandwidth.
• Select PSD units (dBm/Hz or dBm/MHz).
• Toggle power limit and PSD limit testing if you wish to see pass/fail test results.
Channel Power is a constant measurement; after it is turned on, it remains on until a different measurement is selected or the sweep is paused. Channel Power is calculated at the end of each sweep.
SETUP Menu (Channel Power)
The channel power SETUP menu is available in MEASURE > MEASUREMENT > Channel Power > SETUP. After the channel power measurement is selected, the SETUP menu can be quickly accessed by tapping on the summary display area below the spectrum window.
SETUP Menu (Channel Power)
 
INTEGRATION BW
Specifies the range of integration used in calculating the power in the channel. The integration bandwidth (IBW) is displayed as the shaded region between the bandwidth start and stop thresholds (dashed green lines).
PSD UNITS
Sets the unit bandwidth for power spectral density. The available units are dBm/Hz and dBm/MHz.
POWER LIMIT
The power limit is the threshold value used to determine whether the actual measured channel power will pass or not. If the measured channel power exceeds the set power limit, the channel power test fails; otherwise, the test passes. Pass/fail test results are shown in the measurement results table.
PSD LIMIT
If the power spectral density limit is on, it is the threshold value used to determine whether the actual measured PSD will pass or not. If the measured PSD exceeds the PSD Limit, the PSD test fails; otherwise the test passes.
PRESET SETUP
Sets all channel power setup parameters to default. Turns off limits.