A new version of the Lime Suite software bundle for the LimeSDR family of software-defined radio (SDR) devices has been released, bringing with it support for the new LimeSDR Mini 2.
Lime Suite 23.11.0, available now from GitHub and in the Ubuntu Personal Package Archive (PPA) as a pre-built package for Ubuntu 22.04 Long Term Support (LTS), is the latest version of the open-source software bundle for LimeSDR devices – and, for those who haven’t updated in a while, brings with it official support for the new LimeSDR Mini 2 without the need to build from source yourself.
Designed as a next-generation replacement for the popular LimeSDR Mini, the LimeSDR Mini 2 offers the same functionality as the original but with a considerably larger field-programmable gate array (FPGA) – opening the door for custom gateware which can offload tasks from the host and run them directly on-device.
As well as support for the LimeSDR Mini 2, the new release brings with it a handful of bug fixes, including a crash when using the FFT Viewer with X11 forwarding over an SSH connection, and improvements including more readable logs when using a dark mode interface.
Lime Microsystems and its partners on the project have been awarded an Institution of Engineering and Technology (IET) Excellence and Innovation Awards for the Secure 5G Platform, an open radio access network (open RAN) platform built around LimeSDR technology.
Following its funding in 2021 by the Department for Digital, Culture, Media, and Sport (DCMS) and the Future RAN Competition (FRANC), the Secure 5G Platform project – a collaboration between Lime, Slipstream Engineering Design, Arqit, and the Compound Semiconductor Applications Catapult – has demonstrated how software-defined radio technology can provide high-security yet open RAN technology for cellular communications.
Recognising its potential, the IET awarded the project its Communications and IT Award – highlighting its potential to deliver on the United Nations’ Sustainable Development Goals. “The Secure 5G project is proof that democratised open RAN technologies are not a future-gazing prediction but very much a turning point in the present,” says Lime’s chief executive officer Ebrahim Bushehri of the award, “and we’re thrilled that the IET recognises its potential to change the world for the better.”
More information is available on the Lime Microsystems website.
The European Telecommunications Standards Institute (ETSI) has voted to release the algorithms behind Terrestrial Trunked Radio (TETRA)’s cryptographic functionality – after researchers discovered what amounted to a “backdoor” in the system’s security.
Researchers detailed a family of vulnerabilities, dubbed TETRA:BURST, in July this year, with the most severe described as a “backdoor” in the TEA1 encryption algorithm which made it “trivially brute-forceable on consumer hardware in minutes.” While ETSI, the organisation behind the TETRA standard, denied that it represented a backdoor, it promised to vote on the release of the algorithms themselves – and has now confirmed it will be making them available in the public domain.
“Transparency is at the root of ETSI, in our governance and technical work,” claims ETSI director-general Luis Gorge Romero of the organisation’s meeting, in which members voted to release the algorithms. “With their decision at the TCCE meeting, our members proved once again that we evolve with technology and market requirements.”
The release covers the TEA 1 through 7 algorithms, the organisation has confirmed, while stating that it will be “open to academic research for independent reviews” post-publication. It has not, however, yet offered a date for the release of the algorithms, nor detailed the licence terms under which they will be made available.
The FreeDV project, which aims to produce a high-quality digital voice mode for low-bitrate high-frequency radio, has announced the release of FreeDV v1.9.5, bringing a range of bug fixes.
Communications expert David Rowe, PhD, has been working with contributors on the FreeDV project for years – aiming to deliver high-quality voice at a very low bitrate for HF radio use. Among its advantages are its release as open source, including modems and the Codec 2 speech codec, making it easy to integrated into other projects.
FreeDV v1.9.5, the latest release at the time of writing, brings a selection of bug fixes including proper suppression of frequency updates when the frequency control is in focus, support for using USB on 60m frequencies with DIGU/DIGL disabled, and better support for Apple’s macOS Sonoma operating system. Rowe has also detailed work underway on improving Codec 2 and improving fast synchronisation capabilities.
The latest version of FreeDV is available on GitHub, under the reciprocal Lesser GNU General Public Licence 2.1.
Watch Duty, a non-profit set up to monitor and alert wildfire progress and firefighting efforts, has written about its use of software-defined radio technology to build Raspberry Pi-based repeater stations dubbed Echo Radios.
“Broadcastify is the primary source for internet-based police and fire radio traffic. It’s free to use, and thousands of people host well-established feeds, which are essentially radio frequencies connected to the internet,” Watch Duty explains of how it listens out for activity. “Unfortunately, some feeds are unreliable; they go offline or have too much static, and some areas don’t have any feed coverage.
“As a result, our radio scanning reporters struggle to provide accurate and comprehensive reporting due to missed and/or cutoff transmissions. These feeds serve as lifelines not just for the Watch Duty team but also for first responders and the community as a whole – it’s vital that they operate reliably at all times. Echo aims to fix this.”
The Echo Radios are Watch Duty’s answer to the problem: rugged devices built around Raspberry Pi 4 single-board computers linked to a series of low-cost software-defined radios — each of which, rather than scanning the airwaves, is set to a fixed channel specific to the location in which they’re deployed. These signals are then made available over a network, without any of the cut-out problems of scanning alternatives.
“In addition to listening to and uploading audio, Echo actively listens live for ‘tone outs:’ orders for engines, strike teams, and other heavy equipment,” the organisation adds. “These tones are similar to telephone keypad tones but are instead broadcast over the airwaves. Each set of tones equates to a different person or apparatus in the fire service, just like a telephone number would equate to one house or cell phone.”
More information on the project is available on the Watch Duty website.
The Discovery Dish project, which aims to produce a crowdfunded 65cm satellite dish antenna designed for use with software-defined radios to pick up weather satellite transmissions, has published a status report – revealing that the dish could be ready ahead of schedule, if the funding goal is reached.
“We’ve been working on getting manufacturing of the moulds and electronics ready to go once we receive funding. We’re finalising our CAD files and double checking everything so we’ll be ready to go once the campaign ends,” Discovery Dish creator KrakenRF writes. “We put six months as our target before shipping, but we’re hoping to actually get the product out sooner than that. The main delays in the timeline will be the Chinese New Year holidays early next year and the time it will take to sea freight our bulk production runs.”
At the same time, the company has teased potential support for 2.2GHz S-Band feeds. “The return-loss characteristics of the feed were designed to be good at 2.2GHz,” KrakenRF claims, “so we probably don’t need to change much of the core feed design. We are also actively working on our rotator prototype which we hope to release next year as a companion product to the Discovery Dish in order to make reception of polar orbiting satellites easier and more accessible.”
The full project update is available on Crowd Supply, where the Discovery Dish campaign runs until the 14th of December.
Wes “VA5MUD” Pidhaychuk has demonstrated how to build a miniature high-frequency loading coil, as a means to reach bands outside a given antenna’s usual reach.
“Super easy and fun to build, this little guy will get you on bands your current antennas wont touch,” Wes explains. “Simply move the magnetic pickup to get your SWR in a happy place and start yapping! The great thing is you DO NOT NEED A TUNER! Save your money and build something to be proud of and show it off to all the nerds in your life. Budget antenna accessory perfect for POTA [Parks on the Air].”
The device is built using low-cost fasteners and washers, a length of PVC pipe, 21 feet of galvanized steel wire, a magnetic picture hanger and magnetic hooks, and crimp ring terminals – plus a flexible grommet for spacing the wires, which Wes advises can be replaced with a LEGO plate if a suitable grommet isn’t available.
The full assembly guide and parts list is available on Wes’ YouTube channel.
Radio amateur Ben “VE6SFX” Eadie has taken the concept of “radio ham” to its absolute illogical limit – by building a functional antenna out of a can of processed ham.
“I want to take some of the most absurd items that I can find and turn them into ham radio antennas,” Ben explains of his latest video series, dubbed Will It Ham. “For episode one of Will It Ham we are going to use a can of ham – yeah, you heard that right, I’m going to turn a can of ham into a ham radio antenna. Why, might you ask? Because nobody else is.”
The ham in question is pre-cooked pig meat from Maple Leaf, supplied in a metal tin – and, of course, it’s not the meat which will form the basis of the antenna but the tin itself. Using the tin, copper foil tape, and 3D-printed spacers, Ben was able to turn the scrap metal into a functional antenna.
The build process and testing is documented in Ben’s YouTube video, while the 3D print files have been published to Printables under the Creative Commons Attribution-NonCommercial 4.0 International licence.
If you don’t have a can of ham to hand, though, maker Gabe “saveitforparts” Emerson has something else you can upcycle into a working antenna: an umbrella.
“Here it is, the challenge nobody asked for! Can I get L-band satellite data using an umbrella covered in foil tape,” Gabe says by way of background to his latest project. “It turns out, yes I can! I was able to download images and weather data from GOES-East, NOAA satellites, and Russian METEOR satellites. I also got a little bit from some other satellites but the signals weren’t as good.”
That successful reception wasn’t achieved with just an umbrella alone, of course: the project involved applying three full rolls of metal foil tape to the antenna, adding a feed, filter and amplifier, and cabling, then connecting it to a software-defined radio hooked up to a laptop running SDR++ and the Satdump tool for decoding received data.
“Is it cheap? Yes. Is it effective? Yeah, maybe,” Gabe says of the result. “It blows around in the window, it falls apart in the rain, I still haven’t tried to actually fold this up yet – and if I pu this thing in my luggage the TSA is going to just ear me apart. But, theoretically, if I had time on a road trip and I had an umbrella nad some foil tape I could assemble this just about anywhere.”
The full build process is shown in Gabe’s YouTube video.