Lime Micro products, including the LimeSDR family, are still being impacted by global component shortages and supply chain disruption – but Lime’s Ebrahim Bushehri has detailed how the company is working to overcome the issues.

“While we’ve placed our orders and hope the supply chain settles down soon, we’re not betting on it and are actively pursuing other avenues to resuming production,” Ebrahim explains. “For example, there is some hope of synthesizing a PLL in an FPGA and sourcing FPGAs with better availability.

“We’re also seriously considering repurposing perfectly good components on boards that have some other defect and would otherwise be scrapped. Happily, the one part we don’t need to worry about right now is our own – the LMS7002 transceiver, since we fortunately had a large batch produced prior to the semiconductor shortage.”

Anyone who is looking to purchase a LimeSDR, LimeNET Micro, or LimeRFE will now find the latest anticipated shipping dates on the respective Crowd Supply pages; anyone who has already placed an order can log in to Crowd Supply to see updated shipping information for their order.

British Amateur Television Club chair Dave Crump (G8GKQ) has shown off impressive new upgrades for the Portsdown digital TV transceiver project, adding in new “test equipment” functionality.

“I have extended the Signal Generator that was included in the earlier Portsdowns (which used the ADF4351 synth from Analog Devices) to be able to drive a number of output devices including the LimeSDR Mini,” Dave explains of his efforts.

“Based on some code from Phil (M0DNYI) I have [also] written the Portsdown Band Viewer. This uses the receive side of the LimeSDR to provide a view of up to 20 MHz of any band within the Lime’s frequency range with a very simple user interface. It has proved invaluable for weak-signal portable DATV operation, in that you can see the weak signal coming out of the noise before the DVB-S2 decoder gives any indication of locking.”

More information on the new features can be found on the Lime Micro news page; additional detail is available on the respective wiki pages for the Portsdown 4 Signal Generator and Portsdown Band Viewer.

Pseudonymous security researcher Aaron “Cemaxecuter” has shown off a combination of two open-hardware projects in one: A PinePhone smartphone linked to a LimeSDR Mini for on-the-go radio work.

“PinePhone w/ LimeSDR Mini and CubicSDR,” Aaron writes in a brief message accompanying a short demonstration video. In the video, the PinePhone – an open-hardware smartphone running a custom Linux distribution, rather than Google’s Android – is seen connected to a bare LimeSDR Mini via a USB Type-C to USB Type-A On-The-Go (OTG) cable.

The smartphone is shown running the CubicSDR software, tuned to an FM station and happily demodulating while also running a waterfall visualisation. From the brief video, performance seems good – though no interaction takes place, and there’s no mention of battery life while running the LimeSDR Mini.

The full video is available on the cemaxecuter Twitter post.

Attilio Zani, executive director of the Telecom Infra Project, has offered a look at what the organisation has achieved in 2021 – and it makes for impressive reading.

“The strength of our community lies in the recognition and commitment from all parts of the industry that it is only through collaboration that we can implement the change required to sustainably meet the exponential demand for connectivity and bring everyone into the digital economy,” Attilio writes in the forward-looking conclusion to his lengthy retrospective. “The more we work together, the more we can accelerate the pace of innovation.

“This isn’t just limited to companies; we need to be aligned with policymakers and other industry organizations that share our vision and are working to accelerate disaggregation and innovation. Our goal is to bring the ecosystem together and we will continue to collaborate with other industry organizations including GSMA, OCP, ONF, O-RAN ALLIANCE, and WBA, through established liaison agreements.”

Among the achievements listed in the piece are: the scaling-up of productisation for OpenRAN and the Open optical and Packet Transport (OOPT) projects; the launch of OpenWiFi deployments in Africa, India, and Taiwan; the launch of the Fixed Broadband Project Group (FiBr); new deliverables from the Open Core Network; and a partnership with the International Finance Corporation (IFC) for the creation of a way for financial organiations to invest in Network as a Service (NaaS) companies.

The full retrospective is available on the TIP blog.

The Telecom Infra Project has also announced a collaboration on the first-ever 5G private network field trial for healthcare – taking place in the largest hospital in Latin America, Brazil’s Hospital das Clínicas, Faculty of Medicine of the University of São Paulo (HCFMUSP).

“The 5G private network takes the evolution of networks to the next level,” says Sriram Subramanian, technical lead of the TIP 5G Private Networks Solution Group. “Businesses see the potential to reap the benefits of 5G with dedicated infrastructure for an immersive user experience. TIP, in collaboration with Deloitte, NEC, and OEMs (Original Equipment Manufacturers), is providing a platform for all partners to incubate critical Inova healthcare use cases in this field trial, expanding the community’s relevance to enterprise verticals, opening the door to more use cases.”

“This project will positively impact the delivery of patient care – accelerating digitisation, personalised medicine, improving access, and reducing costs,” claims Giovanni Guido Cerri, president of the hospital’s Innovation Commission. “Without a doubt, it will be an impetus for new investments in health and technology development, as well as improving access and reducing inequalities. It will also contribute to improving diagnostic quality and digital health.”

The trial will see the installation of a private 5G network, dubbed OpenCare 5G, which will be used for remote examinations, mobile ultrasound, and more. More details are available in the TIP announcement.

ARRL, the National Association for Amateur Radio, has highlighted the upcoming launch of the ASRTU-1 CubeSat – to include a V/u FM amateur radio transponder and a camera system which can be triggered via radio.

“China’s Harbin Institute of Technology has applied for IARU Coordination of the ASRTU-1 CubeSat,” the ARRL announced this month. “Among other capabilities, the satellite will provide a V/u FM amateur radio transponder.

“A new SDR-based transceiver was developed for ASRTU-1 to provide communication and experiment resources to radio amateurs, including a V/u FM transponder, a UHF telemetry downlink, and a 10.5 GHz image downlink. The satellite will also allow radio amateurs to send commands to control the satellite to take and download images.”

The satellite is scheduled to launch towards the end of 2022, from a site in Russia. More information is available on the ARRL website.

Researchers at Princeton University have developed a thin-film high-frequency antenna array which, they say, could be applied to anything from a patient’s skin to an aeroplane’s wings.

“To achieve these large dimensions [for low-power arrays], people have tried discrete integration of hundreds of little microchips. But that’s not practical — it’s not low-cost, it’s not reliable, it’s not scalable on a wireless systems level,” explains senior author Naveen Verma, a professor of electrical and computer engineering and director of Princeton’s Keller Center for Innovation in Engineering Education. “What you want is a technology that can natively scale to these big dimensions. Well, we have a technology like that — it’s the one that we use for our displays.”

Based on thin-film transistor (TFT) technology, the prototype phased array bundles three antennas into a 30cm row – allowing for point-to-point communications and operable at the frequencies required for 5G and 6G cellular. It can also be installed almost anywhere – including the wallpaper of a room, the researchers say, and on the wings of a plane.

More information is available on the Princeton website, while the paper has been published in Nature Electronics under closed-access terms.

Germany has announced a €300 million (around $336 million) fund for open radio access network (open RAN) projects – as part of a plan to build up its own independent telecommunications industry.

Some of the funding has already been earmarked for a testbed lab, running through 2024, open RAN roll-outs in Neubrandenburg and Plauen, and a research programme surrounding the development of interoperable hardware and components.

“The Open RAN Lab sponsored by us is an open platform that enables the networking of market players and accelerates technical development,” says Minister for Transport and Digital Infrastructure Andreas Scheuer of the programme. “All interested market participants have access and can work together across the board and learn from each other – regardless of whether they are network operators, network suppliers, or new players such as startups or SMEs.”

So far network operators Vodafone, Deutsche Telekom, and Nokia have all confirmed involvement in projects under the open RAN umbrella. More information is available in this RCRWireless report on the topic.

Engineer and radio amateur Dale Thomas has build a custom messaging device, dubbed the HamMessenger, which sends and receives text messages via an off-the-shelf VHF radio via APRS.

“I decided on a dual Arduino approach. An Arduino Pro Mini (US $10) would act as the modem, running MicroAPRS and communicating with the rest of the system via a serial connection,” Dale explains of his project. “An Arduino Mega 2560 ($40) would be the central controller, tying together the modem, keyboard, display, and GPS. Rechargeable batteries with a battery-management board would provide the power.

“The GPS provides the location data that is integrated into most APRS transmissions. I chose a $10 NEO 6M-based GPS receiver that is popular with hobbyists for things such as DIY drones. Like my modem, the NEO has a serial interface.”

Dale’s full project write-up is available on IEEE Spectrum, while design files and source code can be found on Dale’s GitHub repository under the reciprocal GNU General Public Licence 3.

Viol Tailor’s LimeSDR-compatible lightweight uSDR software has been upgraded to v1.4.0, bringing with it a range of improvements including better performance – and lower-latency audio.

Designed for use with Microsoft Windows, the latest release of the software includes newly-customisable tool panels, high-precision WAV IQ file playback, support for a wider range of playback formats, an option to invert the spectrum, manual waterfall colour map modification with fast-switching between palettes, customisable FIFO buffer size with on-the-fly changing, a stereo FM demodulator, a new frequency manager, and improved controls.

The new features come atop the software’s existing selling points, including its small file and memory footprints, its lack of dependence on external frameworks or runtime libraries, a simple user interface, and support for displays ranging from small VGA panels to double-4K large-format setups. The software remains backwards-compatible through to Windows XP and with support for slower CPUs.

The latest version of the software is available to download on SourceForge.

The videos from the GNU Radio Conference 2021 (GRCon21) are now available on YouTube, with a range of talks and lightning sessions available as recaps or for those who could not attend the event live.

Topics covered at the event include: using Conda to manage GNU Radio installations; Debian Bullseye support; using GNU Radio to run interactive radio-frequency Capture The Flag (CTF) events; GNU Radio’s use in the Search for Extra-Terrestrial Intelligence (SETI); reverse-engineering smart meters; a radio resilience competition; an introduction to Multiple Input Multiple Output (MIMO); channel leakage cancellation; open software, hardware, and gateware; mixed-reality visualisations; interior target tracking; deep-space signal reception; defensive 5G; and more.

The full playlist is available on the GNU Radio YouTube channel now.

The Osmocom project has released a new version of the Cellular Network Infrastructure (CNI) stack, 202111, which brings with it improvements made over a nine-month development period.

Among the improvements introduced in the new CNI release are: the option to use name strings, rather than ID numbers, to identify rate_ctr and stat_item groups; AMR fixes; new APIs for base64 encoding and decoding and key derivation functions; a non-blocking logging system; improvements in the NS2 protocol implementation; VAMOS support; A5/4 support; SDCCH8 support for the Osmocom style dynamic timeslots; a number of bug fixes; and heavy refactoring of several sections of the stack.

A full change log is available on the Osmocom website.

The project has also announced that its OsmoDevCall videos are now being hosted on at “We strive to continue to push all OsmoDevCall recordings there to reach a wider audience of like-minded hackers (in the sense of people who want to understand technology down to the last bit and play with it),” Osmocom’s Harald “LaForge” Welte explains, “and ensure long-term availability of our video recordings.”

Pseudonymous programmer Liam “Xerbo” has released an open-source High Resolution Picture Transmission (HPRT) decoder and demodulator, designed to be lightweight: LeanHRPT.

“LeanHRPT is a flexible, easy to use and powerful set of tools for the manipulation of HRPT data (maybe I could be convinced to add LRPT support),” Liam writes of the project. “When used properly LeanHRPT Decode can generate (almost) L1B data usable in actual land/weather observation, or just pretty images.

“The LeanHRPT project also contains LeanHRPT Demod, as you probably guessed, a HRPT demodulator. It features an incredibly high sensitivity as well as being able to do both real-time (through SoapySDR) and offline demodulation (baseband).”

The two tools are available in the LeanHRPT Decode and LeanHRPT Demod GitHub repositories respectively, both under the reciprocal GNU General Public Licence 3.

Hackaday has brought our attention to a neat project designed to visualise Wi-Fi signal strength in 3D space – by using a converted 3D printer.

“I built this thing to visualize how Wi-Fi moves through space,” explains software engineering student Jan Neumann. :To do so I used an old 3D printer frame and an ESP32 NodeMCU. The ESP32 probe was moved in a grid pattern and every 1 cm an RSSI (signal strength) measurement was captured.

“The ESP32 was connected to the old print head and hosted an API with the RSSI measurements. The two axis have been controlled by an Ethersweep controller each and a python script collected and visualized the captured data.”

The result: A three-dimensional cube, the size of the 3D printer’s build area, with 1 cm-resolution signal strength readings. “What I found interesting was the distance between the light and the dark spots in the plot: they were around 12.5 cm which is the wavelength of 2.4GHz Wi-Fi,” Jan writes. “Also, I didn’t think that such low spec test equipment was able to create a detailed map of how Wi-Fi spreads through space.”

More details, and instructions on building your own, are available on Jan’s GitHub repository; an accompanying video shows the project in action.

The Lacuna Space project has announced a milestone for LoRa communication: bouncing a signal off the moon, setting a new distance record.

“For the first time ever we bounced a LoRa message off the moon on October 5th 2021, using the Dwingeloo radio telescope,” Lacuna Space explains of its achievement. “This first was achieved by a team consisting of Jan van Muijlwijk (CAMRAS, PA3FXB), Tammo Jan Dijkema (CAMRAS), Frank Zeppenfeldt (ESA, PD0AP) and Thomas Telkamp (Lacuna Space, PA8Z). The signal travelled an amazing distance of 730,360 km, which to our knowledge is the furthest distance a LoRa modulated message has ever travelled.

“For a short moment the entire message was in space, in between the Earth and the Moon. We transmitted the signal with a Semtech LR1110 RF transceiver chip (in the 430-440 MHz amateur band), amplified to 350 Watt, using the 25 meter dish of the telescope. Then, 2.44 seconds later, it was received by the same chip. One of the messages even contained a full LoRaWAN frame.”

Full details, including a spectrum plot of the received message, are available Lacuna Space website; more information is available in The Register‘s coverage of the achievement.