Antenna used for radiated emissions testing are individually calibrated (the antenna factors
can be measured directly) at all appropriate distances. The calibrations produce values that
are defined the “equivalent free space antenna factor.” The calibration procedure corrects
for the presence of the reflection of the antenna in the ground plane, giving the value that
would be measured if the antenna were in “free space.”
Antenna Editor
Step1.
Once Software Tools has been opened, select
Antenna Editor
from the
Tools
menu on the tool bar. A pop-up box will appear on the screen of the PC.
Step2.
Click on “Edit Antenna” to enter an antenna name, description, frequencies, and
antenna factors. Enter the frequencies in ascending order, starting with lowest
frequency first. A maximum of 60 antenna factors may be entered. Use the ar-
row keys on the keyboard to move between entries. Enter an antenna frequency
and gain only, and Software Tools will automatically calculate the antenna fac-
tor.
NOTE: Only one input of frequency and antenna factor is allowed per row. Mul-
tiple antenna factors for a single antenna must be entered individually. For ex-
ample, an antenna having an antenna factor of 5 from 2.0 to 2.25 GHz and an
antenna factor of 4 from 2.25 to 2.5 GHz should be entered as follows:
If necessary, an antenna factor of zero (0) may be entered.
Step3.
Select
Save
from the
File
menu to save the antenna factors to the hard disk.
Uploading Antenna Factors
All 10 available antennas are transferred to the instrument at the same time. To modify only
a single antenna in the instrument, first download the current antennas (see below) then
modify the appropriate antenna, then re-upload the antennas to the instrument.
To upload antenna information from Handheld Software Tools to the instrument:
Step1.
Connect the RS232 cable between the PC and the instrument.
Step2.
Click on the
Upload
button on the tool bar (or select
Upload
from the
Tools
menu). It is important to note that the instrument must sweep very quickly dur-
ing the data transfer, at least every 5 seconds, or the Handheld Software Tools
program may “time-out.” To improve the chances of a successful upload, in-
crease the RBW and VBW settings to the maximum, or set the span to 0, tempo-
rarily.
Step3.
The antennas available can be viewed by pressing the
MEAS/DISP
key, then
the
Measure
,
Field Strength
and
Select Custom Antenna
soft keys.
10-8
Chapter 10 Handheld Software Tools Program
Frequency (MHz)
Antenna Factor
2000
5
2251
4
2500
4