Receiver Control

Last updated: 2014-11-28

Description

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 as Channel and MS Target Power.

Automatic Receiver Control

Manual Receiver Control

Receiver Control Settings

Expected 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 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:

When Power Control is set to Auto , the Expected Power from the UE is automatically determined by the test set. When Power Control is set to Manual, 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 of Auto.

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

Only available in CW operating mode.

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

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. The upper and lower limits of these settings provide boundaries for the combination of amplitude offset and expected power from the UE.

The Measurement Frequency setting is used to manually tune the test set's measurement downconverter input signal path.

Available in TD-SCDMA Test and CW operating modes.

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

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:

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.

Related Topics

GPIB Commands: RFANalyzer