3GPP2 Signal Analyzer Measurement Guide : EVDO Signal Analyzer : EVDO RF Measurements Setup
EVDO RF Measurements Setup
To make EVDO RF measurements, connect the instrument to the base station following the setup instructions. Press the Measurement and RF Measurement submenu keys to open the measurement menu.
Channel Spectrum Setup
This measurement displays the spectrum of the specified channel and channel power, occupied bandwidth, and peak-to-average power.
1. Press the RF Measurement submenu key to open the RF Measurement menu.
2. Press Channel Spectrum to display the active measurement (Figure: EVDO Channel Spectrum).
EVDO Channel Spectrum
Power vs Time Setup
From the RF Measurement menu, press Power vs Time to display the active measurement. (Figure: EVDO Power vs. Time).
EVDO Power vs. Time
ACPR Setup
ACPR (Adjacent Channel Power 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.
From the RF Measurement menu, use the following procedure for ACPR:
1. Press the ACPR submenu key to activate the ACPR measurement (Figure: EVDO ACPR Measurement). The red dot on the submenu key indicates that it is selected.
2. Press the ACPR submenu key again to specify the Number of Carriers in a multi-carrier configuration and to specify Carrier BW.
EVDO ACPR Measurement
Spurious Emission Setup
The Spurious Emission test examines emissions at frequencies that are outside of the assigned EVDO channel. Spurious emission should be measured at the base station RF output port by using a direct cable connection.
To perform the test, select the correct band class and channel number. A band-class-specific mask will be shown on the screen. Maximum emission power in each frequency offset region will be highlighted by markers. Typical resolution bandwidths (RBW) that are used in the emission test are 30 KHz and 1 MHz. Due to the variable RBW in some band classes, the spectrum can appear to have “steps”.
For accurate EVDO emission measurements, users are required to input an all-idle or all-active signal, and to set the instrument slot setting accordingly. The emission mask is drawn according to the following document: Recommended Minimum Performance Standards for cdma2000 High Rate Packet Data Access Network. (See 3GPP2 C.S0032-A or TIA-864-A for details.)
In the case of a multi-carrier EVDO signal, the “Number of Carriers” setting can be changed (setting it to a maximum of 5 carriers).
When the center frequency of a signal is entered directly (instead of giving Band Class and Channel Number info), the instrument automatically determines the most likely band class and its emission mask, according to the specified frequency.
From the RF Measurement menu, press the Spurious Emission submenu key to activate the measurement (Figure: EVDO Spurious Emission). The red dot on the submenu key indicates that it is selected.
EVDO Spurious Emission