Specifications

User InterfaceGPS and Assisted GPS
37Operating Manual 1171.5248.12 ─ 15
"PRBSxx/Data
List/Pattern"
Arbitrary data can be used for basic tests on the GPS signals.
Arbitrary data are supported only in "Generic" mode.
Data sources "PN9", "PN11", "PN15", "PN16", "PN20", "PN21",
"PN23", "ALL0", "ALL1", and "Pattern" are all available.
If the "Pattern" data type is used, the bit pattern is defined in the "Pat-
tern" input box. The length is limited to 64 bits.
"Data lists" are selected in the "File Select" window, which is called by
means of the "Data List Management" button.
Signals generated in this way can be recognized by a GPS receiver.
However, since there are no real navigation data on the C/A code, only
the signal level of the simulated satellite(s) can be measured and dis-
played by the receiver.
A signal of this type is usually sufficient for performing simple function
tests. It should be noted, however, that the receiver to be tested may
have to be switched to a special test mode, since signals without correct
navigation data are often not indicated (on a display, for example).
SCPI command:
[:SOURce<hw>]:BB:GPS:NAVigation:DATA on page 89
[:SOURce<hw>]:BB:GPS:NAVigation:DATA:PATTern on page 90
[:SOURce<hw>]:BB:GPS:NAVigation:DATA:DSELect on page 89
Select Almanac File
Opens the file manager for selecting the almanac file.
The button is only available if data source "Real Navigation Data" is selected.
The downloaded files can be copied to the R&S Signal Generator via USB interface or
via a LAN network.
Almanacs are currently available at the following internet sites:
U.S.Coast Guard Navigation Center GPS Homepage (http://www.navcen.uscg.gov/
GPS/almanacs.htm)
The almanac files are named xxx.alm (for YUMA files) or xxx.al3 (for SEM files)
whereas xxx denotes the day of a year.
http://www.celestrak.com/GPS/almanac
The naming convention of the almanac file is:
almanac.sem/yuma.weekXXXX.YYYYYY.txt
whereas xxxx denotes the GPS week and
yyyyyy the time of almanac (TOA).
Note: Supported almanac files are SEM-files with data extension *.txt and YUMA
almanac files.
SCPI command:
[:SOURce<hw>]:BB:GPS:NAVigation:ALManac on page 86
Almanac For GPS Week
Indicates the week in which the almanac was published. The simulation time ("Date")
must be set within this time interval.
GPS Main Dialog