Channel Power Measurement; Cdma Channel Power Measurement - Anritsu spectrum master ms2711d User Manual

calculated at the end of a sweep. An hourglass is displayed as the calculations are per-
formed.

Channel Power Measurement

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 in a specific time interval. Out-of-specification power measurements indicate system
faults, which can be in the power amplifiers and in filter circuits. Channel Power measure-
ments can be used to:
Validate transmitter performance
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Comply with government regulations
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Keep overall system interference at a minimum
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Frequency and span settings for many signal standards can be automatically set by pressing
the Frequency key and then the Signal Standard soft key. Choose the desired standard
and press ENTER.

CDMA Channel Power Measurement

MS2711D can be used to measure CDMA signals in terms of channel power. It is necessary
to use precise settings to accurately measure the CDMA signal because the CDMA signal is
different from a CW signal in many respects.
The following are the recommended settings for accurate IS-95 CDMA measurements:
CDMA Channel Bandwidth: 1.23 MHz
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RBW setting: 10 kHz
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VBW setting ³ 3 ´ RBW, or at least 30 kHz
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Averaging function OFF
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Required Equipment
MS2711D Handheld Spectrum Master
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30 dB, 50 Watt, bi-directional, DC –18 GHz, N(m) – N(f), Attenuator
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Test Port extension cable, Anritsu 15NNF50 – 1.5C
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Procedure
Step 1. Reset the MS2711D to the factory default settings for the current mode by press-
ing the RECALL SETUP key on the data keypad. When the key is pressed, a
Recall Setup selection box appears on the display. Select setup location 0 <De-
fault> to recall the factory preset state for the currently selected mode.
Step 2. Using the test port extension cable and 20 dB attenuator, connect the signal
source to the input of the attenuator, and connect the output of the attenuator to
the RF In test port of the MS2711D.
Step 3. Press the AMPLITUDE key and select the Ref Level soft key to set the refer-
ence level to –50 dBm.
Step 4. Select the Ref Level Offset soft key to set the reference level offset to –30 dB.
Chapter 5 Field Measurements
5-3