Developer Wayne Campbell has released version 0.5.1 of rsadsb, a Rust-based ADS-B aircraft tracking system with a text-mode user interface — bringing with it its first support for LimeSDR devices.
“Release v0.5.0 of rsadsb is now released,” Wayne writes of the launch. “Use any SDR supported by SoapySDR. If any HackRF or LimeSDR users want to try my software, MR welcome with gain values!”
Rsadsb is a a collection of utilities, written in Rust and released under an open-source licence, designed for tracking aircraft using Automatic Dependent Surveillance-Broadcast (ADS-B) signals. Where most similar software uses a graphical user interface (GUI), though, rsadsb is designed for use at a terminal via a text-mode user interface (TUI).
In support of the latest release, Wayne has also written up a project log for installation of an in-car ADS-B monitor powered by a Raspberry Pi and using a compact touch-scree to display nearby aircraft.
The latest release, meanwhile, is available on GitHub alongside the source code under the permissive MIT licence.
Electronics engineer Manuel Rios has put together a virtual machine, based on System76’s Pop!_OS Linux distribution, designed to get users started with GNU Radio and LimeSDR as quickly as possible.
“If anyone is interested in SDR and LimeSDR,” Manuel wrote on the release of the virtual machine, “I’ve created a VM image with Pop!_OS from System76. It has GNU Radio, Pothosware, and Wireshark in it.”
The virtual machine, supplied as an OVA file for VirtualBox but compatible with other hypervisor platforms upon conversion, has all software and drivers pre-loaded – making it easier to get started. As a virtual machine, it’s also easy to experiment and roll back if anything goes wrong – without risking breaking anything on the host machine.
Manuel has posted the download link for the OVA file, which comes in at 3.6GB, to Twitter; the password to log in once downloaded is “qwerty”.
Vodafone has announced a partnership with Lime Microsystems and others in the semiconductor industry to develop silicon chips specifically tailored for open radio access network (open RAN) use.
In an interview with Reuters, Vodafone confirmed it was working with Lime Micro, Intel, Arm, Broadcom, and Qualcomm on “its own chip architecture for nascent open RAN network technology.”
The partnership comes after Vodafone joined forces with Lime Micro in 2017 to use LimeSDR-based technology and general-purpose processing platforms to create an app-based ecosystem for open RAN efforts. Since then, the companies have worked closely on projects including the LimeNET CrowdCell.
Vodafone is to coordinate the chip-design effort at its research and development facility in Malaga, and is investigating combining software-defined radio technology with general-purpose cores based on the x86, Arm, and RISC-V architectures.
More information is available on the Lime Micro website.
Radio ham and machine operator Neil Smith has published a video demonstrating the use of a 3D-printable dielectric for microwave and mmWave systems, using a new resin from Rogers Corp: Radix.
“Rogers Corp recently announced Radix, a new 3D printing UV resin for SLA/DLP printers which has a hugely improved performance as a dielectric for creating lenses and beam-forming elements for microwave and mmWave antenna systems,” Neil explains.
“The feature sizes that are possible means we’ll be able to create 3D printed graded-index or GRIN lenses for focussing and refracting microwave and mmWave signals in the range from a few GHz up to at least 47 GHz.
“The material has a dissipation factor/loss tangent of around 0.004,” Neil adds, “which is an order of magnitude better than most UV resins. It beats the ABS filament from Preperm on water absorption and looks like it is going to make possible things we haven’t even thought of yet.”
The full video is available on Neil’s Machining and Microwaves YouTube channel.
NASA’s Jet Propulsion Laboratory (JPL) and Italian aerospace specialist Argotec have unveiled plans to build a satellite constellation in orbit around the moon, with a view to providing near-continuous communications coverage for future missions.
The Andromeda constellation, the two organisations have announced, will consist of 24 relay satellites split into four frozen elliptical orbits spread from 447 miles to 5,027 miles above the surface of the moon. For the lunar poles, the constellation will provide constant coverage for communications with Earth; at the equator, coverage will be available around 79 per cent of the time.
The satellites themselves are based on off-the-shelf hardware, bar a novel metasurface antenna designed for 3D-printing and offering improved performance over rival designs. In addition to finalising the hardware, the team is also working on developing the software required for communications in the S-, X-, and K-bands.
NASA project manager Faramaz Davarian and Argotec head of research and development Alessandro Balossino have written more about the project on IEEE Spectrum.
GNU Radio has published new beginner-friendly tutorials for its graph-based radio software, helping users get to started before diving into more complicated topics.
“The goal is to reduce the learning curve for GNU Radio,” says tutorial author Matt Carrick. “The tutorials cover beginner material up to more advanced concepts: how to use variables and the difference between streams and vectors; creating a custom Python block; reading/writing tags and messages in Python.
“I’d like to make another set of tutorials that the community wants and needs but I need your help! Please let me know how the tutorials can be improved, what is hard to understand in GNU Radio or what you’d like to see a future tutorial on.”
More information on the tutorials, which were sponsored by NumFOCUS, is available on Matt’s blog, where readers can submit feedback via email; the tutorials themselves are live on the GNU Radio wiki now.
Radio ham Giuseppe Morlè has submitted an interesting project to SWLing Post: the build of a test-bench adjustable multi-loop antenna created in the framework of a cheap shoe-rack.
“The frame is a shoe rack in beech wood, very light, to take anywhere or to try out at home,” Guiseppe explains of the project, which he describes as “this umpteenth project of mine built with poor materials.
“On the frame there are four different loops of different sizes and three variable capacitors with different capacities. Only one signal transfer link to the receiver for all loops. With alligator plugs I can use the different combinations of loop / variable to find the best tune. This test rig can tune the whole HF frequency range and medium wave.”
Guiseppe has published three videos demonstrating the use of the unusual antenna test-bed platform; additional details are available on SWLing Post.
Harald “LaForge” Welte has announced the successful validation of a new and more efficient implementation of Time Division Multiplexing emulation over Internet Protocol (TDMoIP), as part of the Osmocom project.
“The high-level goal of the protocol is to be able to carry E1 circuits over IP networks, specifically the public internet,” Harald explains. “The idea is for this to be used in order to interconnect various community/hobbyist folks who experiment with TDM technology at their home, but who have no chance to interconnect with others due to the decommissioning of the pubic PDH/ISDN networks.”
The in-practice validation announced earlier this month saw two icE1usb USB-E1 interfaces with built-in GPS-DO used to transport an E1 line over an intermediate IP network. Stability was monitored over a period of several hours, and the efficiency-improving compression and batching features worked as expected.
“There’s still a lot of work to do to make this more usable via consume internet connections with NAT and dynamic IP addresses,” Harald admits, “but the concepts could be shown to work in practice.”
More on the experiment is available on the Osmocom blog, while details on the proposed TDMoIP protocol itself are to be found on the Osmocom wiki.
Chinese electronics firm elekitsorparts has begun selling a low-cost portable active loop antenna for high frequency (HF) use, built with software-defined radio projects in mind.
“WBL-02 is a portable active loop antenna designed for HF bands for radio receivers,” the company writes. “The antenna consists of a pre-amp box and a loop element that made of a copper electric wire with plastic coating. The pre-amp box has two boards, one is the preamp unit, and the other one is the power supply and battery charging.
“No other tricks needed to operate this antenna, just hook up the loop element, connect the pre-amp box to your radio with a SMA coax, then slide the switch to ON, that’s all. If the batteries run out (LOW BATT LED ON), just connect it to a USB wall charger with our supplied USB-C cable. It will stop charging when the batteries are full.”
The antenna is up for sale on the company’s Tindie store now at $39.99, but comes with a warning that it should be used only for reception and not transmission: “It could be fully damaged if you deliver more than 500mW RF signal to its RF OUT port,” elekitsorparts says.
Finally, SWLing Post has published a guest blog from Bob Colegrove demonstrating how to calculate the distance between stations using Microsoft Excel or a similar spreadsheet application.
“There are a number of Internet sites which let you enter latitude and longitude information and then calculate the distance across the surface of the Earth,” Bob writes. “These are alright on an occasional basis, but I often wind up getting the data mixed for the two locations, and it is not handy when you want to make several measurements. Here’s a way to generate the distance from your home to thousands of stations with just a little effort.
“There are Internet sites which develop earth surface calculations in highly esoteric terms and heavy-duty math. But life is short, and I wanted to cut to the chase. There are, in fact, several formula variations which have somehow managed to distil all this down to a neat single-cell calculation, and they seem to work very well.”
Bob shares two key formula: one for calculating the distance between any two points on earth, and another for converting from degrees, minutes, and seconds to a digital format for calculation. There’s also a bonus tip for automatically pulling down latitude and longitude figures for locations, which comes with the note that “it only works on the current version of Microsoft 365 Excel, and apparently goes off into the big cloud in the sky to instantly download the information.”
The full tutorial is available on SWLing Post now, along with a downloadable version of the spreadsheet used to demonstrate the formulae.