Other Interests-Radio System Design

Other Interests

Raspberry Pi

This is an incredible low cost computer project from the UK. (for example see) It packs a Linux based computer with HDMI, audio and composite video outputs as well as USB and ethernet connectivity onto a credit card sized PCB. It boots from an SD card and can be run either stand alone with keyboard, mouse, monitor etc, or headless, meaning from another computer via the TC/IP port and a terminal program. There is a growing and vibrant development community. At RSD raspberry pi devices are use for a variety of everyday tasks.  One is a dedicated file syncronisation server, working between the lab computers and laptops it keeps project folders in sync as well as providing backup to a NAS storage device.

The recently introduced RPI3 with a faster quad core processor and RPi zero with internal wireless connections further expand the possibilities of use for remote services.

Pluto SDR
Earlier in 2017 Analog Devices released, as part of their educational hardware offering, ADALM Pluto.  This is a fully functional USB powered wideband 1 TRx  SDR with all sorts of possibilities.  Out of the box, it tunes from 325 to 3800 MHz, but with a well documented hack, that can be extended to cover 70 to 6,000 MHz for both Tx and Rx.  There is a useful API to control the device and I have encapsulated that into a python class for other experimenters to play with.  This is available from the RSD git repository.

Amateur Radio

 You might think that innovation in technology in recent years has pushed amateur radio into the background. But it is by no means the case; while computers, the internet and ubiquitous communications technology may seem to make radio sets rather old hat, amateur radio enthusiasts are once again breaking new ground. These very same technologies are being used in new ways for science, interesting experiment and just plain fun. Here are just few topics that those in radio technology can look up and find valuable information from amateur radio enthusiasts:
  • Advanced in radio architecture using Software Defined Radio (SDR), look for the High Performance SDR (HPSDR) project portal.
  • There is even an SDR on the net at the University of Twente, see link 
  • Two very innovative antennas and propagation experiments using very low power, narrow band signals. Both these ideas enhance the reception using very narrow filter bandwidths and with various DSP processing techniques to detect signals, even with negative SNR. So it is simple hardware, the remakable capabilities of low cost personal computers and freely available software that makes it all possible.
  • Weak Signal Propagation Reporter (WSPR, pronounced whisper) a precision timed, narrow FSK signal with tracking and reporting via a global web server. http://wsprnet.org
  • Manned Experimental Propagation tests (MEPT), very low power, narrow band transmissions using QRSS, monitored by volunteer 'grabbers' that visually show the signals received and publish the results on individual web sites.