Using the Adjacent Channel Power Measurement

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Adjacent Channel Power measures the power of the carrier and the power of the noise in its adjacent channels. The measurement results can help you determine whether the power is set correctly and whether the transmitter filter is working properly. Once you have set the limits, you can easily see whether a test falls within those limits using the mask feature and the color-coded metrics. You can measure the adjacent channel power on one to three adjacent channels on each side of your center channel in the CDMA, W-CDMA, TDMA, GSM Edge and GPRS, AMPS, NMT-450, Tetra, iDEN and Korean PCS channel bands.

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CAUTION:

When measuring multiple adjacent channels, the combined channel power must not exceed +20 dBm at the RF In port.

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CAUTION:

The maximum power for the RF In (Port 1) and RF Out/SWR (Port 2) ports is +20 dBm (100 mW). When using the 8481A/8482A Power Sensors, the maximum input power applied to the Power Sensor is +24 dBm (300 mW). When using the 8481D Power Sensor, the maximum input power is +20 dBm (100 mW). When directly coupled to a base station (BTS) or Access Network (AN), the test set can be damaged by excessive power applied to any of these three ports. To prevent damage in most situations when you directly couple the test set to a base station, use the high power attenuator between the test set and the BTS.

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NOTE:

For complex modulation such as CDMA, W-CDMA, 1xEV-DO and GSM, the frequency error measurement is not accurate (see respective analyzers for detailed frequency error results).

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NOTE:

The RF in loss can be added manually or automatically by performing an insertion loss measurement. For measurement instructions refer to "Performing (and Calibrating) a Basic One Port Insertion Loss measurement" or "Normalizing and Performing a Basic Two Port Insertion Loss Measurement"

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