AERIS-10, published as the PLFM_RADAR repository, is an open-source 10.5 GHz phased array radar that transmits pulse linear frequency modulated (LFM) waveforms. The project ships the whole design rather than a paper about one: schematics, PCB layouts, firmware and host software, with the code under MIT and the hardware under CERN-OHL-P. The README names its audience plainly — researchers, drone developers and serious SDR enthusiasts who want to experiment with phased array radar hardware directly. The repository is marked Alpha, with features still listed as work in progress, and it has drawn over 25,000 stars and more than 5,800 forks since it appeared.
What it does
AERIS-10 is a complete radar sensor design at 10.5 GHz. Equipment in this class is normally expensive and closed; here the full build is public and free to copy, fabricate and modify.
The materials describe:
- Two versions of the system: a 3 km variant built around a patch array, and a 20 km variant using waveguide.
- Sixteen array elements that steer the beam electronically, up to 45 degrees in any direction, with no moving parts.
- An on-board FPGA that handles pulse compression, Doppler processing and target detection.
- A Python interface that plots detected targets live on a map.
So the repository covers the chain end to end: the RF front end and antenna, the digital signal processing that turns raw returns into detections, and the operator-facing display that shows where those detections are.
How it works
A pulse LFM radar sweeps the transmitted frequency across each pulse instead of sending a single tone. On receive, the return is correlated against that known sweep, which concentrates a long pulse into a short one — the technique gives fine range resolution without demanding enormous peak transmit power. That is why this waveform is the practical choice for a low-cost design: the cost moves out of the amplifier and into the processing.
The processing is where the FPGA sits. Pulse compression, Doppler extraction and detection all have to keep up with the return stream in real time, which is a poor fit for a general-purpose CPU and a natural fit for fixed-function logic on an FPGA. Only the reduced result — target detections — travels onward to the Python layer, which is doing presentation rather than heavy math.
Beam steering is phase-based. With sixteen elements, the relative phase applied to each one tilts the effective beam, and sweeping those phases sweeps the beam. The stated coverage is 45 degrees in any direction from boresight. A mechanically rotating dish does the same job with a motor; a phased array does it in microseconds and never wears out.
The difference between the two versions is mostly the antenna. A patch array etched on a board is cheap and flat, and the project pairs it with the 3 km range figure. Waveguide is bulkier and harder to fabricate but loses far less at X-band frequencies, and that is the 20 km configuration. Choosing between them is the first real decision a builder makes.
Getting started
Start by reading the README and deciding which of the two versions you want, because that choice drives the antenna work and the parts list. From there the repository gives you the design files directly — board layouts to send to a fabricator, firmware for the digital side, and the software that runs on the host.
Two things are worth being clear-eyed about. The first is that this is hardware: you need fabrication, assembly and RF test gear, and the Alpha status means you should expect to debug the design as well as build it. The second is legal. Transmitting at 10.5 GHz is regulated in most countries, and what you may radiate, at what power, and under which licence is your responsibility to check before you power anything up.
One small oddity in the repository metadata: GitHub reports the main language as PL/SQL, which does not match what the README describes. Treat it as a detection artifact and go by the directory contents.
When to use it / when not
This is the right project if you want to learn how a phased array radar is actually put together, if you are researching detection or tracking and need a real sensor you can modify, or if you are building drone-related systems and want radar you control end to end.
It is the wrong project if you need a finished, certified, supported sensor to drop into a product. An Alpha-status open hardware design with features in progress is a platform for experiments, not a procurement item, and nobody is on the other end of a support contract.
Anyone who has wanted to work with phased array radar and been stopped by price or by closed documentation should take this repository seriously. The interesting part is not any single number in the spec but the fact that the whole stack — antenna, RF board, FPGA signal chain and display software — is open at once, so you can follow a return from the air all the way to a dot on a map and change any stage of it. That combination is rare, and for researchers, drone builders and experienced SDR people it is worth the fabrication effort the project demands.