SoapySDR

AIS-catcher -gu [setting value] ...

In general we recommend to use the built-in drivers for supported SDR devices. However, AIS-catcher also supports a wide variety of other devices via the SoapySDR library which is an independent SDR support library. SoapySDR is not included by default in the standard build. To enable SoapySDR support follow the build instructions below but replace the cmake call with:

cmake .. -DSOAPYSDR=ON

The result is that AIS-catcher adds a few additional "devices" to the device list (-l): a generic SoapySDR device and one device for each receiving channel for each device, e.g. with one RTL-SDR dongle connected this would look like:

Found 3 device(s):
0: Realtek, RTL2838UHIDIR, SN: 00000001
1: SOAPYSDR, 1 device(s), SN: SOAPYSDR
2: SOAPYSDR, driver=rtlsdr,serial=00000001, SN: SCH0-00000001

To start streaming via Soapy we can use:

AIS-catcher -d SCH0-00000001

Note that the serial number has a prefix of SCH0 (short for SoapySDR Channel 0) to distinguish it from the device accessed via the native SDR library. Alternatively, we can use a device-string to select the device:

AIS-catcher -d SOAPYSDR -gu device "serial=00000001,driver=rtlsdr" -s 1536K

Stream arguments and gain arguments can be set similarly via -gu STREAM and -gu GAIN followed by an argument string (if it contains spaces use ""). Please note that SoapySDR does not signal if the input parameters for the device are not set properly. We therefore added the -gu PROBE on switch which displays the actual settings used, e.g.

AIS-catcher -d SOAPYSDR -s 1536K -gu GAIN "TUNER=37.3" PROBE on SETTINGS "biastee=true"

To complete the example, this command also sets the tuner gain for the RTL-SDR to 37.3 and switches on the bias-tee via the SETTING command giving access to the device's extra settings.

If the sample rates for a device are not supported by AIS-catcher, the SOXR functionality could be considered (e.g. -go SOXR on). Again, we advise to use the built-in drivers and include resampling functionality where possible.

Summary Settings

Key	Type	Default	Description
Generic Options
SAMPLE_RATE	integer	0/span>	Sampling rate in Hz (0-20,000,000)
BANDWIDTH	integer	0	Tuner bandwidth in Hz (0-1,000,000, 0=off)
FREQOFFSET	integer	0	Frequency correction in PPM (-150 to +150)
FORMAT	string	CF32	Data type for input source
Specific Options
DEVICE	string	""	SoapySDR device arguments string
GAIN	string	-	Gain settings in key=value pairs
STREAM	string	-	Stream arguments in key=value pairs
SETTING	string	-	Device settings in key=value pairs
ANTENNA	string	-	Antenna selection
AGC	boolean	true	Enable/disable Automatic Gain Control
PROBE	boolean	false	Print actual device settings
CH	integer	0	Channel selection (0-32)