Programming a Loopback Bit Error Ratio Measurement

Last updated: January 16, 2009

This section provides an example of how to make loopback bit error ratio (BER) measurements via GPIB. The following program example assumes that the mobile station's (UE's) antenna output is connected to the RF IN/OUT connector.

The basic procedure to test loopback BER is as follows:

SetUplink DTCH RMC CRC Presence toPresent (see CALL:SERVice:RBTest:DTCHannel:CRC[:PRESence] ).
SetUE Loopback Type toType 1 (see CALL:MS:LOOPback:TYPE ).
Set the loopback BER setup parameters as desired using the SETup:WBERror commands.
Prompt the user to establish anRB Test Mode connection.
Set UE Target Power and Cell Power as needed.
Use the INITiate:WBERror command to start the measurement (see INITiate ).
Use the FETCh:WBERror ? query to obtain the measurement results (or use the READ:WBERror[:ALL]? command to both initiate the measurement and fetch key measurement results as a sequential operation).

Programming Example

 
10     ! Loopback Bit Error Ratio Measurement Programming Example
20     !
30       Testset=714
40     !
50     !***Set up test parameters***
60     !
70       OUTPUT Testset;"CALL:SERVice:RBTest:DTCHannel:CRC:PRESence PRESent"
80          ! Set Uplink DTCH RMC CRC Presence to Present.
90       OUTPUT Testset;"CALL:MS:LOOPback:TYPE TYPE1"
100         ! Set UE Loopback Type to Type 1.
110     !
120     !***Set up measurement parameters***
130     !
140       OUTPUT Testset;"SETup:WBERror:COUNt 10000"
150         ! Set Number of Bits to Test to 10000.
160       OUTPUT Testset;"SETup:WBERror:CONTinuous OFF"
170         ! Set Trigger Arm to Single.
180       OUTPUT Testset;"SETup:WBERror:CONFidence 99.80"
190         ! Turn Confidence State On and set Confidence Level to 99.80%.
200       OUTPUT Testset;"SETup:WBERror:REQuirement 0.10"
210         ! Set BER Requirement to 0.10%.
220       OUTPUT Testset;"SETup:WBERror:CONFidence:DUTFactor 1.5"
230         ! Set Bad DUT Factor to 1.5.
240     !
250     !***Establish a connection***
260       PRINT "Establish an RB Test Mode connection between the UE and test set."
270       PRINT "Press F2 to continue."
280       PAUSE
290     !
300     !***Set up test parameters***
310     !
320       OUTPUT Testset;"CALL:MS:POWer:TARGet 21"
330         ! Set UE Target Power to +21 dBm.
340       OUTPUT Testset;"CALL:POWer -106"
350         ! Set Cell Power to -106 dBm.
360     !
370     !***INITiate and FETCh measurements***
380     !
390       OUTPUT Testset;"INITiate:WBERror"
400         ! INITiate the measurement
410       OUTPUT Testset;"FETCh:WBERror?"
420       ENTER Testset;Integ,Ber,Error_count,Bits_tested
430       OUTPUT Testset;"FETCh:WBERror:RATio:FAIL?"
440       ENTER Testset;Conf_test
450         ! FETCh and READ Loopback BER measurement results
460     !
470     !***Print measurement results***
480     !
490       CLEAR SCREEN
500       PRINT "Loopback BER Measurement Results:"
510       PRINT
520       PRINT "Integrity Indicator                   = ",Integ
530       PRINT "Bit Error Ratio (%)                   = ",Ber
540       PRINT "Bit Error Count                       = ",Error_count
550       PRINT "Bits Tested                           = ",Bits_tested
560       PRINT "Confidence Test Result                = ",Conf_test
570       PRINT "(0=Pass, 1=Fail, 2=Max Bits Tested)"
580     !
590       END

Programming a Loopback Bit Error Ratio Measurement

Programming Example

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