Receiver Control

Last updated: January 15, 2009

You can manually tune the test set's receiver frequency and attenuation settings for the frequency and power level that you want to test. Or, you can have the test set automatically tune its receiver's frequency and attenuation settings based on other settings such asUplink Channel andUE Target Power .

Automatic Receiver Control

Automatic receiver control is the default for all operating modes except CW Operating Mode (only manual receiver control is available in CW operating mode). With automatic receiver control, the test set automatically tunes to the correct frequencies for making measurements and maintaining a call based on the Uplink Channel setting. Also, the test set adjusts attenuation settings according to the power level that should be present at the RF IN/OUT port given the current settings. This power level is referred to as the Expected Power .

Manual Receiver Control

In some instances, you may want to control the test set's receiver settings manually rather than allowing the test set to automatically control them. This ability is referred to as manual receiver control. Manual receiver settings can be used to override some or all of the automatic receiver settings. You can manually set the Expected Power , the measurement downconverter's tune frequency ( Measurement Frequency ), and the demodulation downconverter's tune frequency ( Uplink Frequency ).

In CW operating mode, you must always specify what frequencies and power the receiver should tune to, there is no automatic receiver control.

Receiver Control Settings

The following settings control the test set's receivers:

Power Control

Available inActive Cell ,FDD Test andCell Off operating modes.

WhenPower Control is set toAuto , the Expected Power from the UE is automatically determined by the test set. WhenPower Control is set toManual , the expected power is determined by the Manual Power setting.

Note, when you switch between operating modes,Power Control is returned to its default value ofAuto .

GPIB command: RFANalyzer:CONTrol:POWer:AUTO

Manual Power

Available inActive Cell ,FDD Test andCell Off operating modes.

When Power Control is set toManual , the Expected Power from the UE is determined by theManual Power setting. Note, when you switch between operating modes,Power Control is returned to its default value ofAuto .

GPIB command: RFANalyzer:MANual:POWer[:SELected]

Expected CW Power

Available inCW operating mode.

TheExpected CW Power setting determines the Expected Power while in CW operating mode.

GPIB command: RFANalyzer:CW:EXPected:POWer

NOTE

You can set the


 Expected CW Power

and


 Manual Power

levels beyond the actual capability of the test set's hardware. This is because these settings are intended to reflect the potential range of RF power at the UE. This range of RF power is meant to accommodate the use of a gain or loss network between the mobile station and the test set (see Amplitude Offset ). The upper and lower limits of these settings provide boundaries for the combination of amplitude offset and expected power from the UE.

Measurement Frequency

Available in all operating modes.

TheMeasurement Frequency setting is used to manually tune the test set's measurement downconverter input signal path (see Block Diagram ).

GPIB commands:

RFANalyzer:MANual:MEASurement[:MFRequency] - Specifies a measurement frequency and sets control mode to manual.
RFANalyzer:CONTrol:MEASurement:FREQuency:AUTO - Specifies manual or auto control mode. When in auto control mode, the measurement frequency is automatically determined by the Uplink Channel setting.
RFANalyzer:MANual:MEASurement:FREQuency - Specifies a measurement frequency.

Note, when you switch between operating modes,Measurement Frequency is returned to its default value ofAuto .

Uplink Frequency

Available inFDD Test andCW operating modes.

TheUplink Frequency setting is used to manually tune the test set's demodulation downconverter input signal path (see Block Diagram ). The demodulation downconverter signal path is used to establish and maintain the call (RF link) between the UE and test set.

GPIB commands:

RFANalyzer:MANual:UPLink[:MFRequency] - Specifies an uplink frequency and sets control mode to manual.
RFANalyzer:CONTrol:UPLink:FREQuency:AUTO - Specifies manual or auto mode. When in auto control mode, the uplink frequency is automatically determined by the Uplink Channel setting.
RFANalyzer:MANual:UPLink:FREQuency - To specify an uplink frequency.

Note, when you switch between operating modes,Uplink Frequency is returned to its default value ofAuto .

Expected Power

To make accurate measurements, the test set needs to know how much power to expect at its RF IN/OUT port; this is referred to as the expected power. If a measurement uses autoranging, the expected power level is calibrated by the test set before making the measurement and does not need to be set by the user. For measurements that do not use autoranging, the test set determines the expected power level in one of several ways:

ForActive Cell operating mode:
- when Power Control is set toManual , expected power is determined by the Manual Power setting.
- when Power Control is set toAuto :
  - if the call status isIdle , expected power is determined by Initial PRACH TX Power or Initial DPCCH TX Power .
  - if the call status isConnected , expected power is determined by the UE Target Power setting.
ForFDD Test operating mode:
- when Power Control is set toManual , expected power is determined by the Manual Power setting.
- when Power Control is set toAuto , expected power is determined by the UE Target Power setting.
ForCW operating mode, expected power is always determined by the Expected CW Power setting.

If the received signal is above or below the acceptable range for expected power, an Over Range or Under Range message is displayed and the measurement's Integrity Indicator is set to 5 or 6, respectively.

Effects on Receiver Control When Changing Operating Mode

After selecting the operating mode and setting one or more receiver controls to manual, the receiver control settings remain as you set them until you change operating mode. Changing operating mode causes some or all receiver parameters to return to automatic control.