Hi everyone! This is my first post here and since its March aready (somehow?!) I figured I should let people know where I'm at.
For my pitch to be a challenger I discussed integrating single pair ethernet (SPE) and power over datalines (PoDL) with some really advanced single chip radar solutions from TI, namely the IWR6843. The AoP (antenna on package) version of this chip means you don't have to be a RF wizard to use them, you can just put them on your PCBs and talk to them over UART or SPI. They have 4 transmitters and 3 receivers, so unlike other mmWave radar sensors they aren't made just for presence detection, but can actually output a point cloud like those commenly used for SLAM (simultaneous localisation and mapping) in robotics.
The devkit (shown above) is quite pricey and it turned out to be cheaper to just build my own. This meant I could also strip out any uncessary components, and I had some fun trying to make it as small as possible ;). It ended up measuring just 26mm * 18mm, not bad considering it needs four voltage rails to operate!
But how to connect it? I put an FPC connector on the board which exposes the UART, but this is a single pair ethernet challenge after all. I've had an idea for a while to create ethernet PHY 'modules' that allow a plug and play approach to SPE. The idea behind this is to put all the SPE and PoDL stuff on a PCB that can be plugged into any microcontroller board with an ethernet MAC in order to give it power and data transmission. The first of these modules I've designed is for 1000BASE-T1 shown below (shoutout to the Molex 2209570001 connector!):
The other part of this stackup is a microcontroller board with an STM32N6, which is a chip I've wanted to try out for a while. I'll only be using it as a bridge between UART and ethernet here, but I've put on a connector for a camera that I intend to use in a future project. The STM32N6 is a beefy chip with an Arm Cortex M55 running at 800MHz with an NPU and MIPI CSI! Putting it all together with a flexible PCB we get the following assembly:
This has all been assembled and is set to arrive soon and in the meantime I've started working on the software, more to follow in future updates! I'll be open sourcing everything after the competition too in case anyone is interested!
