Technical data

Chapter 3 79
1xEV-DO Analyzer and Over Air Test
Optional 1xEV-DO Tx and Over Air Analyzer Measurement Settings
1xEV-DO Analyzer and Over Air
Test
Setting the PN Offset
The PN Offset is a “short code” sequence that provides a unique identifier for each
sector of each cell site. The PN Offsets are applied to the I and Q signals before
modulation. PN Offsets are offset in time by 52.08 µs and they repeat every 26.666
ms. This yields 512 unique short code sequences (0-511). The access terminal needs
the PN Offset to decode information in the Pilot and MAC channels, which are
transmitted by the access network.
If you have selected Auto PN Offset, the displayed PN Offset result corresponds to
the PN Offset of the Pilot sequence with the highest power. If you have selected
Manual PN Offset, the result displayed corresponds to your chosen PN Offset.
The number of slots over which the acquistion is made is determined by the
Measurement Interval, which itself is determined by the Measurement Time. For
more information, refer to “Setting Measurement Time” on page 83.
Setting the PN Increment
The PN Increment allows you to choose the increment step for the PN Offset search
when PN Offset is set to
Auto. Typically the PN Increment is set to 1 when
measuring 1xEV-DO transmitter performance while connected to the access
network via RF cable.
The PN Increment field enables you to search based on a step size of your choice. If
PN Increment = 1 (default), the search will step through PN values by one PN at a
time. If PN Increment = 5, it will step through PN values 0, 5, 10, and so on. The
Measured PN displayed will be a multiple of 5, even if the actual PN is not a
multiple of 5. If you know that all access networks in the area have fixed
increments, then set the PN Increment field to that increment value. If you don’t
know, then use the default value of 1.
Step Notes
1. [Freq/Chan/Time]
2. [PN Offset] Each time you press this softkey, the selected
option changes.