Last updated: December 2, 2008
The test set normally sets all receiver parameters automatically using data connection control settings. You may want to control the test set's receiver parameters manually rather than allowing the test set to control them. This ability is referred to as manual receiver control.
This section details how to access the Receiver Control parameter.
Receiver Control
) from the
Call Setup
screen. A full or partial preset of the test set, including cycling power, returns the test set back to auto mode.The following program examples use simple commands to perform a single function. Complex commands that enable manual receiver control and set a specified parameter at the same time are also available. See RFANalyzer for a listing of all receiver control syntax.
OUTPUT 714;"RFANalyzer:CONTrol:MEASurement:FREQuency:AUTO OFF" !Enables manual control of the measurement receiver's frequency.
OUTPUT 714;"RFANalyzer:MANual:MEASurement:FREQuency 825.030 MHZ" !Tunes the measurement receiver to 825.030 MHz through manual receiver control.
OUTPUT 714;"RFANalyzer:CONTrol:MEASurement:FREQuency:AUTO ON" !Returns measurement receiver frequency tuning control to auto.
Manual control parameter values are stored internally (as long as the test set is powered on). Enabling manual control of a parameter without providing a new value causes a previously stored value to immediately take effect. This allows you to pre-define manual control parameter values in your program before enabling manual control.
To make accurate measurements, the test set needs to know how much power to expect at the test set's RF IN/OUT port; referred to as the Expected Power. It gets this value from the call control MS TX Level setting during automatic receiver control, or by the user specifying the expected power with the expected power control set to manual.
You can set the expected power level beyond the capability of the test set's hardware because expected power is intended to reflect the potential range of RF power at the DUT . This range of RF power is meant to accommodate the use of a gain or loss network between the DUT and the test set. See Amplitude Offset for details about amplitude offset.
The upper and lower limits of expected power provide boundaries for the combination of amplitude offset and expected power. If you set expected power to +52 dBm and the amplitude offset to -3 dB, the calculated receiver power will be 49 dBm, but the test set shall be set to +43 dBm, the upper limit of the hardware. If the calculated value of receiver power goes below -25 dB, the lower limit of the hardware, the test set shall be set to -25 dB.
The expected power from the mobile is set manually using the following settings:
To set the test set receiver's expected power setting to manual use RFANalyzer:CONTrol:POWer:AUTO .
OUTPUT 714;"RFANalyzer:CONTrol:POWer:AUTO OFF"
To set the power level that the test set's receiver is expecting the mobile station uplink burst to transmit at for the GPRS system type, use RFANalyzer:MANual:POWer:BURSt<[1]|2|3|4|5|6|7> . Each burst is set individually.
For example, the commands below set the receiver's expected power setting for burst 1 and burst 2.
OUTPUT 714;"RFANalyzer:MANual:POWer:BURSt1 15 DBM"
OUTPUT 714;"RFANalyzer:MANual:POWer:BURSt2 19 DBM"
NOTE: Setting the manual expected burst power will not set expected power control to manual.
It is recommended that you specify the expected power each time you perform a handoff to a new band or traffic channel type during manual receiver control. This ensures that the correct expected power is set for the new channel settings.
Measurement frequency is used to tune the test set's measuring receiver for all bands:
OUTPUT 714;"RFANalyzer:MANual:MEASurement 942.6 MHZ" !Enables manual measurement !receiver control and sets the test set's measurement receiver frequency to 942.6 MHz.
If the receiver control parameter is set to auto, the test set's receiver frequency is set using the parameters in the following table. See CALL:TCHannel[:ARFCn][:SELected] traffic channel details and CALL:TCHannel:BAND for traffic band details. See CALL[:CELL]:BAND<[:SELected]|:GSM> for cell band details. See CALL:BCHannel for broadcast channel details.
| Cell Off | ||
| GSM BCH+TCH | ||
| GPRS BCH+PDTCH | ||
| EGPRS BCH+PDTCH | ||
Measurement Channel in BCH Only Mode sets which channel is measured by the test set in BCH Only operation mode. You can choose to measure one of the following channels: RACH, TCH or PDTCH.
OUTPUT 714;"CALL:OPERATING:MODE GBTest" !Sets the operating mode to GSM BCH.
OUTPUT 714;"RFANalyzer:CONTrol:BTESt:CHANnel TCH" !Sets the Measurement Channel in GSM BCH Only Mode to TCH.
You are suggested to set the
"Measurement Frequency" on page 7
and
"Expected Power Control" on page 6
to
Auto
when selecting a measurement channel in BCH Only Mode. the test set's receiver frequency and Expected Power Level is set automatically using the parameters in the following table.
| Measurement Channel | |||
|---|---|---|---|
| RACH | |||
| TCH | TCH MS TX Level | ||
The Measurement Channel in BCH Only Mode receiver control parameter is only applicable to the following operating modes:
If the operating mode is set to
GSM BCH
,
PDTCH
is greyed on the front panel; if the operating mode is set to
GPRS BCH
or
EGPRS BCH
,
TCH
is greyed on the front panel.
When Operating Mode is switched from one BCH only Mode to another:
Uplink Frequency sets the test set's demodulation receiver frequency, used to demodulate information from the mobile's uplink transmission:
OUTPUT 714;"RFANalyzer:MANual:UPLink 942.6 MHZ" !Enables manual demodulation !receiver control and sets the test set's demodulation receiver frequency to 942.6 MHz.
The expected modulation format is used by transmitter measurements which support both GMSK and 8PSK signals. The Modulation Format Control parameter allows you to select either Auto or Manual mode.
If the modulation format control is set to Auto, the test set determines which modulation format to expect based on the current Operating Mode, current System Type, and the current Uplink Modulation and Coding Scheme. Coding Schemes MCS-1, MCS-2, MCS-3, and MCS-4 use GMSK modulation while MCS-5, MCS-6, MCS-7, MCS-8, and MCS-9 use 8PSK modulation.
The following table indicates which modulation format the test set expects based on each combination of operating parameters.
| System Type |
Uplink Coding Scheme (CS) or Modulation and Coding Scheme (MCS) |
||
|---|---|---|---|
| Active Cell (GSM) | GSM | N/A | GMSK |
| Active Cell (GPRS) | GSM | N/A | GMSK |
| GPRS | CS1 - CS4 | GMSK | |
| Active Cell (EGPRS) | GSM | N/A | GMSK |
| EGPRS* | MCS1 - MCS4 | GMSK | |
| MCS5 - MCS9 | EPSK | ||
| GSM BCH | GSM | N/A | GMSK |
| GSM BCH+TCH | GSM | N/A | GMSK |
| GPRS BCH | GPRS | CS1 - CS4 | GMSK |
| GPRS BCH+PDTCH | GPRS | CS1 - CS4 | GMSK |
| EGPRS BCH | EGPRS | MCS1 - MCS4 | GMSK |
| MCS5 - MCS9 | EPSK | ||
| EGPRS BCH+PDTCH | EGPRS | MCS1 - MCS4 | GMSK |
| MCS5 - MCS9 | EPSK | ||
| CW | N/A | N/A | GMSK |
| Cell Off | N/A | N/A | GMSK |
If the modulation format control is set to Manual, you can set the modulation format the test set should expect for each uplink burst individually.
OUTPUT 714;"CALL:MODulation:CONTrol:AUTO OFF"
OUTPUT 714;"CALL:MODulation:MANual:BURSt EPSK"
OUTPUT 714;"CALL:MODulation:MANual:BURSt2 EPSK"
Modulation Format Control is only available in Active Cell (EGPRS), EGPRS BCH, and EGPRS BCH+PDTCH operating modes. Attempting to change the modulation format control parameter value in other operating modes generates the following error:
Operation rejected: Command is not supported in this operating mode.
You can make changes to the expected modulation format for each individual uplink burst in any operating mode programatically using GPIB commands. These parameters are only accessible via the front panel when the operating mode is valid for this parameter.
Changes to operating mode cause the modulation format control parameter value to be reset to Auto. However, the individual burst settings are not reset and retain any changes you have made.
The expected CW power from the mobile is set manually using the following setting:
To set the power level that the test set's receiver is expecting the mobile station to transmit at in CW operating mode, use RFANalyzer:CW:EXPected:POWer .
OUTPUT 714;"RFANalyzer:CW:EXPected:POWer 15 DBM"
See Expected Power Control for more information on expected power settings.
Measurement Burst sets the mobile uplink burst number on which the measurement is performed (not the absolute timeslot number, but the burst number relative to the first uplink burst in the TDMA frame):
OUTPUT 714;"CALL:PDTCH:MSL:MEAS:BURS 2" !Sets the receiver to measure the second uplink !burst.
The Measurement Burst parameter is always controlled manually. The choice of bursts available is based on the selection table shown under the multislot selection command, CALL:(PDTCH|PDTChannel):MSLot:CONFig .
After selecting the operating mode to use 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 all receiver parameters to return to automatic control.
For information about this parameter see the description in the GPIB command for this parameter, which is located at CALL:MS:TX:BURSt:GPLength .
This parameter is located in the Receiver Control menu on the front panel. Refer to How Do I Access the Receiver Control Parameters? for instructions on how to access this menu.
For information about this parameter see the description in the GPIB command for this parameter, which is located at CALL:MS:TX:FRAMe:SEGMentation .
This parameter is located in the Receiver Control menu on the front panel. Refer to How Do I Access the Receiver Control Parameters? for instructions on how to access this menu.