TestTree RF-Catcher User manual

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RF-Catcher Suite –Handle a GPS signal
RF-Catcher is the most compact & portable RF Capture & Playback device and spectrum analyzer.
Covering a frequency range from 70 MHz to 6 GHz, RF-Catcher can record & play real-time RF
bandwidth of up to 55 MHz.
RF-Catcher Application Suite extends RF-Catcher capacities with a wide range of software
applications: IQ Converter, IQ Splitter, Event Trigger, RF TroubleMaker, Task Scheduler…
How to capture/playback a GPS signal with RF-Catcher
This setup has been validated with the Spring’17 release of RF-Catcher Application Suite.
STEP 1 –HW requirements
You will need:
•RF-Catcher (+ PC)
•Active GNSS antenna
•GPS splitter
•SMA cables
Note that when playing back the GPS signal on RF-Catcher, it takes a few seconds to get the
lock LED (next to the GNSS antenna on RF-Catcher) to light up.
The lock mechanism of the GPS receiver takes some time, which is normal.
STEP 2 –GPS CAPTURE
We will work with a GPS L1 signal (1575.42 MHz)
Here is how to setup RF-Catcher:
•Connect GNSS active antenna to
the splitter’s DC in port
•Connect RF-Catcher’s GNSS in to
the splitter’s port B
•Connect RF-Catcher’s RF Rx in to
the splitter’s port A (DC Block)
Then configure the following Rx parameters in RF Capture & Playback application:

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RF-Catcher Suite –Handle a GPS signal
You can adjust gain to get an optimal carrier through the “Autoset Gain” button.
Important: Make at least a 45 seconds-long record (1 min 30 typ.) to have time to lock when
playing back the signal.
STEP 3 –GPS PLAYBACK (test setup)
Here is how to setup RF-Catcher to test a GPS recording:
•Connect RF-Catcher’s RF Tx out
to the splitter’s DC in port
•Connect RF-Catcher’s GNSS in to
the splitter’s port A (DC Block)
Then configure the following Tx parameters in RF Capture & Playback application:
The GPS LED on RF-Catcher should light up after a few seconds.
If it does not, try changing the attenuation in GUI and/or using the attenuation value that com-
pensates the gain used during the record.