Dealing with different RTL-SDR dongle you may hear about that in some applications a correct PPM value is essential that a specific type of software is working correctly. So what is PPM and how do i find it out ?
It is an Android app that decodes AIS messages transmitted by vessels , ships, over radio using a cheap USB DVB-T /RTL-SDR stick.
AIS messages are transmitted over VHF. Channel A: 161.975 MHz Channel B: 162.025 MHz. The app decodes both channels simultaneously. This app needs no internet connection, it decodes the real time received messages. This is a truly standalone full featured AIS receiver.
The received messages will be translated into NMEA0183 strings which can be forwarded then via UDP or TCP streaming to third-party apps, PC programs or other devices. Such Apps can display the received AIS data for example on a map along with information about the received objects.
Please note: The app needs additional (very cheap) hardware to receive the radio signals.
Cheap AIS dual channel AIS receiver
Low power consummation
Easy to install
Receive VHF AIS radio signals via DVB-T / RTL SDR USB Stick
Decode AIS messages into NMEA0183 strings ( !AIVDM )
Send this messages via Network (UDP/TCP)
Device location (GPS,Network) translation into NMEA strings
location NEMA forwarding via Network (UDP)(GPGSV,GPGSA,GPZDA,GPRMC,..)