RTL-SDR AIS Ship Tracking: Difference between revisions

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The frequency of AIS signal is 161.975 MHz and 162.025 MHz, and have the max range of about 70 km. Is is a line of sight signal.  
The frequency of AIS signal is 161.975 MHz and 162.025 MHz, and have the max range of about 70 km. Is is a line of sight signal.  


''Quarter wave / dipole''. One vertical 1/4 wave element connected to the center of the coax cable and 4 (or more) more grounding elements pointing towards the the ground at 45 deg.
''Quarter wave / dipole''. One vertical 1/4 wave element connected to the center of the coax cable and 4 (or more) more grounding elements pointing towards the the ground at 45 deg. A quarter wave antenna calculator: https://jeroen.steeman.org/Antenna/Quarter-Wave-Antenna-Calculator


''Coax collinear antenna''. Very high omnidirectional gain. Multiple short coax cables where the outer conductor is connected to the inner conductor in an alternating fashion.
''Coax collinear antenna''. Very high omnidirectional gain. Multiple short coax cables where the outer conductor is connected to the inner conductor in an alternating fashion.

Revision as of 11:09, 13 June 2024

Introduction

  • AIS: Automatic Identification System.
  • RTL
  • SDR: Software Defined Radio
  • Also: ADS-B (Automatic Dependent Surveillance-Broadcast) for aircraft surveillance. 1090 MHz

Need a radio dongle, antenna. Use Arduino and RPi.

RTL-SDR V3

My dongle seems to be original, according to https://www.rtl-sdr.com/rtl-sdr-blog-v-3-dongles-user-guide/

V3 Datasheet is at https://www.rtl-sdr.com/wp-content/uploads/2018/02/RTL-SDR-Blog-V3-Datasheet.pdf

  • Install the custom drivers in order to make the V4 work
    • RTL-SDR Blog driver fork from https://github.com/rtlsdrblog/rtl-sdr-blog.
    • Release.zip file from the Releases page. For SDR# extract the rtlsdr.dll file from the x86 folder to the SDR#. For most other x64 programs, use the rtlsdr.dll file in the x64 folder.

Software

SDRSharp


Frequencies 161.975 MHz and 162.025 MHz

AirSpy

Theory -- AIS decoding

https://www.rtl-sdr.com/rtl-sdr-tutorial-cheap-ais-ship-tracking/


Radio Dongle

https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/

https://www.ebay.com/str/rtlsdrblog

https://www.ebay.com/itm/283144516411?mkcid=1&mkrid=711-53200-19255-0&siteid=0&campid=5338814417&customid=&toolid=20012&mkevt=1

Antenna

The frequency of AIS signal is 161.975 MHz and 162.025 MHz, and have the max range of about 70 km. Is is a line of sight signal.

Quarter wave / dipole. One vertical 1/4 wave element connected to the center of the coax cable and 4 (or more) more grounding elements pointing towards the the ground at 45 deg. A quarter wave antenna calculator: https://jeroen.steeman.org/Antenna/Quarter-Wave-Antenna-Calculator

Coax collinear antenna. Very high omnidirectional gain. Multiple short coax cables where the outer conductor is connected to the inner conductor in an alternating fashion.

Yagi antenna. Very directional antenna that will pick up signals in the direction it is pointed: Very large gain.

Slim Jim.

Refs:

Programming

References