Category: Navigation

Introduction In the previous post I looked at using OpenPlotter3 for receiving HF Weather Fax (Ref.1). In this post we will use OpenPlotter3 to receive Marine MF NAVTEX (Ref.2). NAVTEX transmissions contain valuable marine information such as navigation warnings, weather forecasts, ice information and MSI specific messages. The world is divided into different regions and… Continue reading OpenPlotter3 – Marine NAVTEX

Introduction Recently I revisited OpenPlotter after a two year interval to see what had changed in the latest version 3 (Ref.1/2). I tested the Starter and Headless images and setup AIS & GPS on OpenCPN. In 2021 I had looked at various aspects of version 2 (Ref.3/13). In this post I will look at the… Continue reading OpenPlotter3 – Marine HF Weather Fax

Introduction In previous posts I looked at various aspects of GMDSS/DSC using Scicos (Ref.2/7). In the last post I built a BFSK Random Data Generator on GNU Radio and in this post I use the random data produced to test a BFSK BPF decoder on GNU Radio. BFSK BPF Decoder Schematic Figure 1 shows the… Continue reading Marine GMDSS/DSC VHF Decoder_b

Introduction In previous posts I have looked at various aspects of GMDSS/DSC using Scicos. In this post I look at a BFSK generator for DSC VHF using GNURadio. The advantage of GNURadio is that it can be directly interfaced with the RTL-SDR and can decode in real time. GNURC Schematic Parameter DSC VHF BFSK Fc… Continue reading BFSK Generator on GNURadio

Introduction In previous posts I looked at receiving GMDSS/DSC HF & VHF signals using a Windows 10 laptop with SDRangel & Multipsk as well as a RaspberryPi4B with Gqrx & GNURadio (Ref.1/5). I also simulated the VHF DSC signal using Scicos (Ref.2). In this post I will make an initial pass at decoding the VHF… Continue reading Marine GMDSS/DSC VHF Decoder_a