‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On Friday, January 31, 2020 9:03 AM, jim bell wrote: ... Check out the Walabot. [1]https://the-gadgeteer.com/2016/11/15/walabot-diy-review/ I don't know how they do this, Is it some sort of mini-phased-array radar? yup, phased arrays and (less) expensive signal processing. see also: millimeter wave imaging, synthetic aperture radar, synthetic aperture imaging. best regards, --- E.g.: [2]https://www.electronicspecifier.com/products/frequency-control/duo-o ffer-development-kits-for-4d-millimetre-wave-imaging Mini Circuits has expanded its collaboration with 4D radar imaging pioneer, Vayyar, to offer researchers in the Radio Frequency / microwave industry and academia a ready-to-use, 4D millimeter wave (mmWave) imaging and sensing application development platform. The VTRIG-74 is a mmWave imaging and sensing development kit powered by Vayyar’s high resolution integrated RF transceiver technology and radar IP. This kit enables researchers and application developers to explore and rapidly develop mmWave imaging and sensing applications without the cost and overhead of building their own bespoke hardware. Potential applications already include industrial IoT, robotics, smart homes, motion and obstacle detection, vehicular operator and passenger detection, medical patient monitoring and many more. The kit comprises Vayyar's high performance transceiver chip with the entire mmWave front-end and analogue baseband signal chain for up to 40 antennas. Key features of the kit include: * Out-of-the-box ready mmWave transceiver module for 4D imaging and sensing application development * 20 transmit by 20 receive integrated antenna array for high resolution 4D imaging * Flexible operation anywhere within the 62-69GHz band * Real time data processing of transmit and receive pair phasors for each swept frequency point * Pre-configured profiles to adjust receiver resolution and imaging processing time * Complete API for Python and Matlab ... References 1. https://the-gadgeteer.com/2016/11/15/walabot-diy-review/ 2. https://www.electronicspecifier.com/products/frequency-control/duo-offer-development-kits-for-4d-millimetre-wave-imaging