The crowdfunding campaign for the LimeRFE, a software-definable front-end module designed for use with LimeSDR hardware, has blown past its funding goal – with over a month left on the clock.
Designed to be used with LimeSDR and LimeNET hardware, the LimeRFE is an open-hardware design with open-source software and adds multi-band power amplification (PA) and low-noise amplification (LNA) alongside filtering. Programmable using the Arduino IDE, the LimeRFE is customisable and suitable for use in amateur bands spanning the spectrum from High Frequency (HF) to 3.5GHz alongside cellular bands and a wideband mode designed for use with external filters.
The LimeRFE boards are schedule to ship to backers in November, with pricing – now the ten Early Bird tiers have been taken – set at $599 for the LimeRFE or $900 in a bundle with a LimeNET Micro, the latter creating an all-in-one platform for radio and general-purpose processing work.
Full details are available on the Crowd Supply campaign page.
Over on the LimeSDR Crowd Supply page is the latest entry in the Field Report contest: Andrin Doll’s report on a bit-pattern generator aligned with the SDR data stream.
“The LimeSDR devices provide a versatile transceiver that suits a number of applications that require reception and transmission at radio frequency. Of particular interest is the use of this low-cost SDR in scientific research and academia, as the frequency range is adapted to a number of experimental techniques,” Andrin writes. “However, in order to incorporate an SDR into such experiments, synchronisation with external devices is often crucial. In my case, the technique of interest is magnetic resonance with either nuclear spins or electron spins.
“I modified the FPGA firmware such that four GPIO outputs represent four bits of the TX stream. A TX data packet thus consists of 16 bits in total: 12 bits for the DACs and 4 bits for the GPIO. Importantly, the LimeSuite API already implements streams with 16-bit data, which is natural given the bus width of the USB interface.”
The full Field Report is available on the LimeSDR Crowd Supply page.
Lime Microsystems has released the first details of a new entry in the LimeNET family ahead of the opening of a crowdfunding campaign: the LimeNET CrowdCell, based on technology developed for the CrowdCell initiative of the Telecom Infra Project (TIP).
Designed as a single unit combining both high-performance general-purpose processing (GPP) and LimeSDR-based software defined radio (SDR) capabilities, along with support for the LimeNET App Store for rapid switching of roles, the LimeNET CrowdCell is capable of operating as an LTE cellular relay to form a ‘crowd’ network in order to rapidly expand coverage, while using an existing macro network for backhaul.
As with Lime Micro’s other entries in the open-hardware LimeNET family, the LimeNET CrowdCell will be launching via crowdfunding site Crowd Supply. Interested parties can read more about the LimeNET CrowdCell and sign up to be notified when the campaign goes live over on Crowd Supply now.
The British Amateur Television Club (BATC)’s Dave Crump has teased an enhancement to the LimeSDR-based Portsdown TV Transmitter project: a switch which toggles between stock FPGA gateware and a custom release that vastly improves performance for digital TV transmission.
Following the release of the a modified LimeSDR Mini gateware optimised for DVBS use late last month, Dave has confirmed that its performance improvements are impressive enough to warranty adding a software switch to the BATC’s Portsdown digital TV transmission software.
Having verified, via the forum, that it would be possible to rewrite the gateware of a LimeSDR Mini roughly twice a day for 15 years without wearing out the FPGA, Dave is now going to investigate releasing a version of Portsdown which can switch the LimeSDR into DVBS-optimised mode and back again – meaning it’ll be possible to get the benefits of the customised firmware without having to worry about manually switching from the stock firmware and back again.
More information on Portsdown is available on the BATC wiki.
The Radio Society of Great Britain (RSGB) and the International Amateur Radio Union (IARU) have warned of a threat to amateur radio from plans to make the 144 MHz and 23cm bands secondary-only for amateur use.
“The IARU was represented this week at the meeting of CEPT Project Team A – one of the groups leading WRC-19 preparations – which finished in Prague on Friday, 21 June 2019,” the RSGB writes in its report. “Of particular interest were discussions on two proposed agenda items for WRC-23, concerning the sharing of the 1240 – 1300 MHz band with the Galileo satellite navigation system and the proposal from France to study a range of frequencies, including the 144 MHz amateur band, for future primary aeronautical applications.
“The IARU and RSGB views with grave concern any proposal to include the global amateur and amateur satellite 144 MHz primary band in the proposed aeronautical agenda item; and will be making every effort to fully protect amateur radio interest and seek the support of regulators in this regard.”
More information is available on the RSGB website.
Hackaday has brought a project by Pete Juliano to our attention: a scratch-built software-defined radio, dubbed the RADIG.
“I am focusing my efforts to literally scratch build an SDR RADIG. For those who don’t know the term RADIG it is a contraction of two words that I coined: Radio and Rig,” Pete explains by way of introduction to the project. “Radio in the sense there are many commercial product building blocks such as Raspberry Pi 3 and a StarTech Sound Card. Oh lest I forget, software in the form of QUISK. The Rig part is the homebrewed detector board, the bi-directional amplifier board, driver board and the final amp.
Building on an earlier project from Charlie Morris, Pete warns that “the skills required to undertake such a project are very likely beyond the skills of someone who has never homebrewed a radio project or one with just a smattering of knowledge on which end of the soldering iron is the hot end.” Nevertheless, he walks through its design and creation – and, most recently, posted a video proving its functionality.
More information is available on Pete’s website.
Finally, the Libre Space Foundation has announced a call for abstracts for the Open Source Cubesat Workshop 2019, taking place in Athens on the 14th to the 16th of October.
“Open source software and hardware is raising in popularity and acceptance on all areas of life, so why not apply it to space exploration as well? The Open Source Cubesat Workshop was created exactly for that: to promote the open source philosophy for CubeSat missions and further,” the event’s organisers explain. “The third edition of the workshop takes place at Athens, Greece hosted by Libre Space Foundation.
“CubeSats have proven to be an ideal tool for exploring news ways of doing space missions: therefore let’s remove the barrier of confidentiality and secrecy, and start to freely share knowledge and information about how to build and operate CubeSats. This workshop provides a forum for CubeSat developers and CubeSat mission operators to meet and join forces on open source projects to benefit from transparency, inclusivity, adaptability, collaboration and community.”
Full details, and a link to submit an abstract for review, can be found on the official website.