Introduction Recently I was approached for advice on frequency scanning. My first thought was a traditional approach of starting at the base frequency, stepping by the channel spacing and doing a power evaluation. If greater than a threshold, then hold and attempt a decode. Before building a prototype in GNU Radio, I thought I would… Continue reading RTL-SDR for VHF Marine Scanner on SDR#
Category: Electronics
Electronics: Hardware, Simulation Software, Microcontrollers
HF Messaging with OFDM_a
Introduction Communications for blue water sailors is extremely important. Reliable satellite communications for voice, email and GRIB weather files has become common place. This service is expensive, however, depending on usage. HF communications for voice & email is another alternative. This has the conventional drawbacks of propagation reliability, connectivity and bandwidth. There are several commercial… Continue reading HF Messaging with OFDM_a
RTL-SDR for AIS & ADS-B on Local Map+
Introduction In previous posts I looked at receiving both AIS & ADS-B on SDRangel (Ref.1) as well as displaying them on OpenCPN using a combination of aisdeco2 & MULTIPSK (Ref.2). The immediate application for this is for an off shore oil/exploration rig, where knowledge of local ships is important (AIS), as well as incoming/outgoing helicopters… Continue reading RTL-SDR for AIS & ADS-B on Local Map+
SDR for QO-100 Satellite Reception – Planning
Introduction Recently I read an interesting post on an sdr newsgroup discussing the Es’hail 2 satellite also known as QO-100 (Qatar Oscar 100). This is a geostationary satellite designed for DBS or direct broadcast television transmission to North Africa and the Middle East (Ref.1). The satellite has Ku (12-18GHz) and Ka (27-40GHz) band transponders for… Continue reading SDR for QO-100 Satellite Reception – Planning
RTL-SDR for Inmarsat Satellite – Dish vs Patch Antenna
Introduction In the previous post I looked at using my L band equipment to receive Inmarsat satellite signals. I was able to receive two satellites from my location at Toronto Harbourfront: 4F3 (Az=206deg) & 3F5 (Az=54deg). From my home QTH, I am only able to receive a partially blocked 3F5. I did a quick test… Continue reading RTL-SDR for Inmarsat Satellite – Dish vs Patch Antenna