Anritsu 3GPP, Measurement Manual

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W-CDMA/HSPA+ Signal Analyzer 3-4 W-CDMA/HSPA+ RF Measurements
3GPP MG PN: 10580-00234 Rev. Y 3-9
ACLR Measurement Setup
ACLR (Adjacent Channel Leakage Ratio) is defined as the ratio of the amount of leakage
power in an adjacent channel to the total transmitted power in the main channel and is
displayed in table format under the bar graph. The 3GPP standard specifies one main
channel and two adjacent channels. The ACLR screen displays the main channel power and
the power of two adjacent channels on each side as a bar graph.
The channel spacing is –10 MHz, –5 MHz, +5 MHz and +10 MHz and the channels are color
coded. The 3GPP standard requires the adjacent channel power leakage ratio to be better
than 45 dB at 5 MHz offset and 50 dB at 10 MHz offset.
ACLR measurements can be made for multi-channel systems by measuring the main
channels and the adjacent channels, from one to four channels. The ACLR screen can display
up to 12 channels total.
In the ACLR measurement mode the filtered channel power is used to determine ACLR
values and is listed as filtered on the display.
The following procedure is for one main channel two adjacent channels.
ACLR Measurement Procedure
1. Set the measurement frequency using one of the methods listed in the User Guide.
2. Press the
Measurements
main menu key.
Figure 3-2. Channel Spectrum