Anritsu Spectrum Master MS2720T, Руководство пользователя

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CDMA Signal Analyzer 2-8 CDMA Measurement Descriptions
3GPP2 MG PN: 10580-00235 Rev. D 2-15
2-8 CDMA Measurement Descriptions
Code Division Multiple Access (CDMA) is used in spread spectrum systems to achieve
multiple access. The frequency spectrum of a signal is spread by using a code that is not
correlated with the data signal. This code is unique to each recipient. A distinction can be
made among signals because the codes are chosen to have low cross-correlation values. By
matching the send and receive codes, the receiver is able to properly translate the message or
data.
RF Measurements
Channel Spectrum
This function includes (below the measurement display) a table view of Channel Power
(in dBm and Watts), Occ BW, and Peak To Avg Pwr.
Occupied BW
The occupied bandwidth is calculated as the bandwidth containing 99% of the transmitted
power.
Peak to Average Power
This is a ratio of the peak envelope power to the average power, in dB.
Spurious Emission
This function includes a measurement display with eight fixed markers. The marker values
are displayed below the measurement and include the power and frequency at each marker
along with a pass fail indication.
ACPR
This function displays from 1 to 5 channels (carriers) and two adjacent channels on each side.
The power of each channel is displayed below the measurement graph and includes the
frequency and power in each of the 4 adjacent channels.
RF Summary
This function displays a table view of Channel Power (in dBm and Watts), Spurious Emission,
Occ BW, and Peak To Avg Pwr.
Demodulator Measurements
Code Domain Power
Code Domain Power (CDP) displays how much of the channel power is in each Walsh Code.
Power is normalized to the channel power and, therefore, a code reading of –10 dB means that
the power in that code is 1/10th of the channel power. The upper half of the measurement
display shows all of the channels, and the lower half shows a zoom view of selected channels.
The number of zoom channels and the starting position (relative to the upper display) are set
with CDP submenu keys for Zoom and Zoom Start Index. A colored background in the upper
display indicates the channels that are in the lower, zoom display. Colors are applied
according to
Table 2-1 :
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