The Background

A few people are looking at me and asking the question – why are we still developing with BLE 4.2 instead of BLE 5 for our new small low power sensors. After all, we all want mesh, we all want longer range, we all want the latest tech …… or do we

The Answer (at the time of writing this post)

There are a number of factors to consider

• Price – last we checked the CC2640S1 module costs under US$5 (100 off price) – yup, until we see a BLE 5 module at the same price point with ceramic antenna or ipx connector option, this point is hard to beat for a small low power sensor
• Range – 50m outdoors is enough in most cases, lets talk about sub 1G for longer range and getting though obstructions. That better range for BLE5 comes at a cost, its a lower data rate, the TX time is longer, that’s more power being consumed. And then you still have the penetration issues at 2.4G
• Power – Mesh doesn’t come free when it comes to power consumption, so its power wiring for Relay Nodes / Friend Nodes, hmmm, not very different to a gateway
• Phones and Tablets – I can wander into BigW (aka local dept. store) today and get a fairly decent phone with bluetooth 4.2 with BLE supported, not locked to a carrier – for about two hundred bucks, if you can do that for BLE 5 please let me know (update, I dropped my old phone in the drink, $80 at Coles prepaid with BLE 4.2)
• Raspberry Pi 3 B+ Ethernet WIFI BLE 4.2 (POE hat coming) – respectable gateway hardware at a reasonable price (there are even cellular hats)
• ESP32 Ethernet BLE 4.2 WIFI – realistic boards from reputable suppliers available for gateway hardware – such as Pycom GPy
• and other boards for gateways and sophisticated BLE 4.2 hardware such as mediaTek MT7697 …….

I’ll agree, the new BLE 5 hardware from Nordic and TI looks good, and there is no denying that longer advertising payload would enable encrypted data, and the idea of making lights etc BLE 5 relays / friends makes a lot of sense, but until the rest of the eco system catches up, and the BLE 5 module price comes down (yes, we see that happening already), we think BLE 4.2 for small low power sensors still has merit.