About
The Wi-Fi HaLow Shield connects your OpenMV AE3 to the world using the Morse Micro MM8108, a second-generation Wi-Fi HaLow (802.11ah) SoC operating in the sub-GHz bands from 850MHz to 950MHz. Unlike 2.4GHz Wi-Fi, sub-GHz signals travel much farther and pass through walls, foliage, and machinery far more effectively, giving you over a kilometer of range in open air.
The MM8108 supports 1/2/4/8MHz channel widths and MCS0-10, including sub-GHz 256-QAM modulation for up to 43.3Mbps at 8MHz. That's enough bandwidth to send images, not just sensor readings, and perform firmware updates. The integrated power amplifier delivers up to 26dBm (400mW), and receive sensitivity reaches -108dBm, so you can trade throughput for distance by dropping to a narrower channel and a lower MCS when you need to reach further. Full RF specifications are in the MM8108 datasheet.
Because Wi-Fi HaLow is still Wi-Fi, it's native IP. Your existing socket code, MQTT, and HTTP all work unchanged. There's no gateway translation layer and no proprietary protocol stack to learn. Security is WPA3 with Protected Management Frames (PMF) and Opportunistic Wireless Encryption (OWE), with hardware AES and SHA-2 acceleration. For a primer on the technology itself, see the Wi-Fi Alliance's Wi-Fi HaLow resources.
The MM8108 offers four low-power modes: Hibernate (<1uA), Deep Sleep (<2uA), Snooze (<20uA), and standby with SDIO from 29uA. Combined with the shield's power inputs below, this lets you deploy a camera that sleeps, wakes to capture and run inference, transmits only the result, and goes back to sleep, all on batteries and a kilometer from the nearest access point.
The AE3 WiFi HaLow Shield powers your OpenMV AE3 from a 1.8V to 5.5V source connected using a standard 2.1mm DC barrel jack (see the 2-pin JST to 2.1mm Connector). This is perfect for powering your OpenMV Cam from three alkaline batteries in series using a standard battery holder with a 2.1mm DC plug. Two alkaline batteries in series also work, although the full capacity of both batteries cannot be used completely before the battery shield shuts down.
You may attempt to use four alkaline batteries in series; however, the fully charged voltage of four alkaline batteries in series may slightly exceed the onboard buck/boost converter's maximum allowed voltage. Proceed with caution.
The shield also features a wide voltage range 6-36V input (see the 2-pin JST to wire leads), which is robust to reverse voltage and features robust transient surge protection. Use this input to power your OpenMV Cam from 12/24V power supplies without having to worry about damaging your camera. This input can be used at the same time as the 1.8V to 5.5V input.
Finally, the shield has a 3.7V 1S LiPo battery charger onboard capable of charging an attached LiPo battery at up to 100mA sourced from either the wide voltage range 6-36V input or 5V USB from the OpenMV AE3.
Note that the 1.8V to 5.5V input directly bypasses the onboard battery charger. The battery shield is designed to draw microamps of current in operation, allowing you to deploy an OpenMV AE3 to run for years on alkaline batteries while your OpenMV AE3 is in deep sleep.
Applications
This shield is perfect for customers who need to deploy the OpenMV AE3 far beyond the reach of regular Wi-Fi, across a factory floor, a farm, a job site, or a parking lot, without trenching cable or paying a monthly cellular bill. Regular 2.4GHz Wi-Fi gives up at the far end of a building, and LoRa has the range but nowhere near the bandwidth to move an image or update your firmware. Wi-Fi HaLow sits right in between, which makes it a natural fit for an OpenMV AE3 that runs inference on-device and transmits detections instead of video.
