Hello, it’s a pleasure to greet you. I need some information and would like to know if you can help me with a maritime project. I’m currently trying to find a way to detect marine fishing buoys from a fishing vessel. These buoys are satellite buoys that typically operate in the L-band frequencies of 1616-1626 MHz (Iridium or Imarsat), emitting Short Burst Data (SBD) bursts. With a small SDR, I’ve managed to capture the signal from the buoy, but only at a distance of a few meters with a large Noeelec antenna and a SAW LNA filter. The problem is that I don’t want to capture the satellite signal, but rather the signal emitted by the buoy itself. The buoys emit a weak signal; I’m not interested in the message they transmit, but rather in knowing their approximate location within at least 2 nautical miles or at least 5 km. Could the hardware you sell help me with this? I want to know the direction of the incoming signal and its proximity. I know other antennas are needed for this, so I’m asking for your advice. If you have anything else to offer, in short, I want to detect the direction of signals from L-band buoys.
It’s very tricky to separate two signals running on the same band, especially if they’re overlapping from one another. To maximize your chances of avoiding the satellite signals, you’d want to find or build an antenna and specifically has gain out to the horizon, rather than to the sky. None of the commercial antennas for Iridium will do that, so it will most likely need to be an antenna you build yourself. A simple L-band quarter wave ground plane might work well.
Be aware that for L-band direction finding with Kraken, you also need very precise cable matching - ideally phase matched by a lab.