Agilent Technologies 8935 series e6380a Manuale Utente

CDMA Measurements - Screens and Control Fields

If you have the IS-2000 option installed, you will be able to select the 
I/Q PLOT screen from the set of available measurements.

The I/Q Constellation Diagram screen graphically shows I/Q decision 
points. This is a useful troubleshooting tool when investigating Rho 
problems

Visual presentation helps identify IQ errors. 

 shows no 

errors. However, the 4 point groupings could be skewed away from 
perfect square or offset indicating a phase error. This will result in 
interference from I to Q and from Q to I. Phase errors can result from 
crosstalk between I and Q in the base station baseband processing 
section, misaligned LOs or intermodulation between Walsh codes.

There are two ways to provide your Base Station’s PN Offset value to 
the Test Set:

• Enter the value directly. See 

• Have the Test Set determine the value from the received signals. See