Introduction In previous posts I looked at receiving Inmarsat satellite signals (Ref.1/2). I used an L band dish and patch antenna. I was wondering what the overall SWR of these antennas looked like, so I decided to test them with the NanoVNA. The NanoVNA that I purchased was spec’d to 1.5GHz, but I guessed that… Continue reading Inmarsat Patch Antenna Testing with NanoVNA
Author: Jeremy Clark
Jeremy Clark is a Senior Telecommunications Engineer and Advanced Amateur Radio Operator VE3PKC. He is the author of E-Books on Telecommunications, Navigation & Electronics.
FEC Forward Error Correction on GNU Radio
Introduction In previous posts I examined the possible use of OFDM for HF messaging (Ref.1/2/3) and for voice (Ref.4). I introduced several channel models using Scicos: an 8 channel discrete model and a 64 channel model using IFFT/FFT. In this post I will focus on using FEC Forward Error Correction to improve the transmission performance.… Continue reading FEC Forward Error Correction on GNU Radio
HF Messaging with OFDM_c
Introduction In previous posts I examined the possible use of OFDM for HF messaging (Ref.1/2) and for voice (Ref.3). I introduced several channel models using Scicos: an 8 channel discrete model and a 64 channel model using IFFT/FFT. In the last post I concentrated on the IFFT transmitter. In this post I will focus on… Continue reading HF Messaging with OFDM_c
HF Messaging with OFDM_b
Introduction In previous posts I examined the possible use of OFDM for HF messaging (Ref.1) and for voice (Ref.2). I introduced several channel models using Scicos. In this post I will expand my Scicos 8 channel model to a 64 channel model generated by IDFT. OFDM IFFT/FFT 64Ch Model In order to obtain the benefits… Continue reading HF Messaging with OFDM_b
Lunar Distance – DST to EST
Introduction Saturday November 5th was an ideal evening to measure a Lunar from my balcony. It was unseasonably warm at 20degC and I had just removed all the gear, as my balcony is going to be rebuilt for the third time in five years, so I might as well enjoy the last few jack hammer… Continue reading Lunar Distance – DST to EST