Yagi Antenna for 138MHz Satellite Weather

Introduction Receiving Satellite Weather signals at 136/138MHz has been very exciting over the past several years. NOAA15/18/19 are now deactivated, but Meteor M2-3 & M2-4 are still available. I was able to receive these signals at Toronto Harbourfront with an open sky view (Ref.1). However, at my home QTH, this proved to be difficult with… Continue reading Yagi Antenna for 138MHz Satellite Weather

Signal Simulation Real R & Complex C

Introduction When I first started working with simulation software such as ScicosLab/Scicos fifteen years ago (Ref.1/2), I used Real signals. Later on when working with GNU Radio I discovered it was also possible to generate Complex signals. It is worth considering the differences between the two approaches. Fourier Transform Let’s do a quick review of… Continue reading Signal Simulation Real R & Complex C

Carrier Synchronization with Costas & Squaring Loops -Simulation

Introduction Costas & Squaring Loops are key components in reception of Telecommunication Signals. They are used to synchronize a local generated carrier with an incoming received carrier. We can simulate and study their operation using Scicos (Ref.1). First we generate a BPSK waveform at R=100bit/sec to use with our two Demodulators (Ref.2). BPSK Waveform Generation… Continue reading Carrier Synchronization with Costas & Squaring Loops -Simulation

Satellite QPSK/OQPSK Simulation

Introduction Many satellite systems such as Meteor & Inmarsat use QPSK Quadrature Phase Shift Keying type modulation. There are various types of QPSK that enhance certain properties such as OQPSK Offset QPSK. We can simulate these signals in Scicos to study their differences (Ref.1). QPSK Scicos Simulation Figure 1 shows a Scicos schematic used to… Continue reading Satellite QPSK/OQPSK Simulation