The first 868MHz Wi-Fi for the Raspberry Pi costs $ 70, but offers up to a mile range

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It has been six long years since the Wi-Fi Alliance named its new addition 802.11ah marketing name HaLow. At the same time, the certification of the new equipment did not begin until the end of last year. The pace is slow, but the potential is huge.

HaLow, unlike your fast home wireless internet, focuses on IoT networks and in Europe on frequency 868 MHz. That is, the former vision was that each home router would be equipped with a receiver in addition to the usual 802.11bgn / ac / ax communication protocols. 802.11ah, who will use the electronics of the Internet of Things, various sensors, smart home, etc. to transmit simpler data.

The 868 MHz band promises a much higher range up to about a kilometer at the cost of lower speed 150 kbps to 15 Mbps. In short, while you would enjoy fast Netflix on Wi-Fi 5/6 at home, a sensor in a beehive on the opposite side of the garden, where the classic Wi-Fi signal does not reach, would run on HaLow.

The first HaLow for the Raspberry Pi

On paper, everything looked nice already in 2016, however, it was worse with real products. For many years, virtually none existed, and other wireless protocols began to fight for a place in the field of IoT. In fact, HaLow seemed to be dead forever. But the situation is finally changing a bit, although it is still a long way from the ideal state.

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The first expansion board with HaLow for the Raspberry Pi

A beautiful example is the expansion board / HAT for Raspberry Pi AHPI7292S (datasheet) from Alpha, Taiwan. It is the world’s first HaLow transmitter for the Raspberry Pi with Newrac NRC7292 chip and Qorvo RFFM6901 radio front end.

So far very expensive

The important thing is that after clicking on the Raspberry Pi and downloading the image with a modified Linux system, you will turn the British Raspberry into HaLow Wi-Fi AP, or station. Since there is so much other iron with HaLow as saffron, the manufacturer expects to buy exactly two expansion boards and test 802.11ah simply by creating a wireless link between the pair of Raspberry Pi.

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The manufacturer provides a system image and instructions on how to run one HaLow AP and HaLow client to create an 802.11ah network

However, domestic do-it-yourselfers are disappointed by the price, which is still really high. Hat with HaLow has the American e-shop Rockland in stock for $ 70, for example. And since you need at least two boards (and the Raspberry Pi for them) for a real test, the investment, plus VAT, customs and postage, costs thousands.

We can only hope that in time HaLow will expand to other, and especially cheaper prototyping kits. The Maker scene would certainly be pleased if the 802.11ah protocol was adopted by, for example, Espressiff engineers, who gave the world the very popular and successful Wi-Fi microcontrollers of the ESP8266 and ESP32 series.



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