Introduction VOR VHF Omni-Directional Range is an aircraft navigational system developed just before WWII and implemented after the war. It operates in the VHF band from 108.0 – 118MHz (Ref.1). It is gradually being replaced by newer GNSS systems. Nevertheless, I decided that it would be an interesting experiment to receive VOR signals and attempt… Continue reading VOR VHF Omni-Directional Range – Splat! Path Analysis_a
RTL-SDR for VHF Air Band AM on GNU Radio
Introduction In previous posts we looked at various ways to use the RTL-SDR with GNU Radio on either Raspberry Pi4 or Windows. In this post we look at the RTL-SDR for VHF Air Band (108-137MHz) reception on GNU Radio. The latest version of GNU Radio >=3.8xx is used (Ref.1). RTL-SDR for Air Band Setup The… Continue reading RTL-SDR for VHF Air Band AM on GNU Radio
SSB Modulation on GNU Radio
Introduction In the previous post we looked at the RTL-SDR for SSB reception on GNU Radio (Ref.1). In this post we look at how to build an SSB modulator using the Hartley Phasing method (Ref.2). The latest version of GNU Radio >=3.8xx is used (Ref.3). Hartley Phasing SSB Modulator Classically there have been three different… Continue reading SSB Modulation on GNU Radio
RTL-SDR for SSB on GNU Radio
Introduction In the previous two posts we looked at using the RTL-SDR on Raspberry Pi4 with GNU Radio. We examined four applications: displaying the FM band spectrum, wide-band FM, narrow-band Marine weather, and finally AM reception. In this post we look at the RTL-SDR for SSB reception on GNU Radio. The latest version of GNU… Continue reading RTL-SDR for SSB on GNU Radio
QAM Quadrature Amplitude Modulation – Analog
Introduction In previous posts we looked at AM Amplitude Modulation for analog transmission (Ref.1) and QAM Quadrature Amplitude Modulation for digital transmission (Ref.2). In this post we will examine QAM for analog transmission. We first look at sending two independent tones; one tone on the In Phase I channel and another tone on the Quadrature… Continue reading QAM Quadrature Amplitude Modulation – Analog