perpendicular to me) reduced its range by as much as 50%. This beacon (and probably most) is quite strongly directional. I imagine this varies based on the position and type of antenna built into the phone. The 45deg angle seems about optimum - for this phone at least. There are a lot of significant variables here that will have an impact on real-world use experience. I logged the approximate distance threshold when the beacon registered in the app as I approached it. I faced the beacon and held the phone in front of me at a natural angle - say 45deg. These numbers were obtained with clear line of sight to the beacon, with the beacon facing me and my Sony Z3C running Google's Physical Web app. I got the following rough range estimates: Tx Power With these beacons, this defaults to 0.95s, with a configurable range of 0.1 - 10s Apart from transmit power, the other key parameter is the advertising interval. ![]() ![]() It has a nominal capacity of 1000mAh 3V which puts it in the ballpark of 2 AAA cells. In the battery powered unit, the CR2477 is a chunky cell. I can see if I can run it through my multimeter to try and get a measurement, but clearly power requirements are low. But even at full power it does not register on a milliamp scale. I plugged in the USB-powered device via a USB power monitor, which shows voltage and current draw. ![]() Google's Physical Web app does allow editing of the URL field, but not the other parameters. As this is GATT, any similar app should work, and perhaps some are better than others. Clearly the assumption is that some installer or IT specialist is going to be configuring the beacons. There is some short explanation of possible values and what they might mean in the app, and more in the technical docs To be honest, this is not a user-friendly experience. Both are put into "configuration mode" by resetting (unplug/re-plug or remove/replace the battery.) They revert to their normal configured mode after 30 seconds.Īccent publish an android app (also I think an iOS app) for configuring them, this appears to be a simple app that lists and allows editing for each of the GATT attributes. I received a kit of 3 USB-powered beacons from Accent Systems (iBKS-USB) and 3 of the button cell (CR2477 Lithium Cell) iBKS-105 beacons. I don't yet know if the battery status for a given beacon can be determined remotely. For a more permanent installation, it will be necessary to replace batteries periodically. For an event or short-lived installation, the sealed units may be fine. Expected use and the ease of maintenance will be factors in which product to chose. Estimates for battery life range from 12mo to 9 years. Some beacons have a provision for mains power - via a wall wart or USB adapter, others are powered by sealed/built-in LiPo batteries, or replaceable AA or coin cells. Transmit power is one of the main factors that determines battery life and power usage of a beacon: more power = more range = shorter battery life. We should expect a theoretical maximum of 100m, and a real-world maximum of about 50m. There is more information about the max range as the BLE spec calls for comparable range to Bluetooth Classic, and max range is one of the key parameters manufacturers list for each product. In theory it should be possible to dial down the minimum beacon range to say 1cm. However, what this means in practice isn't clear as an implementation may or may not expose this for configuration, and it may not allow the full range. This indicates "Programmable Transmitter Output Power: -18 dBm to +5 dBm". In trying to understand minimum and maximum range, I went looking at the datasheet for one of the chips widely used for the BLE beacons: Configured with iOS, Mac and Android apps.Rad Beacon Dot, $14 each - supports simultaneous beacon protocols.Comes pre-configured, at purchase time (presumably can re-configure?).Dev tools to broadcast, scan and detect (Mac).Proximity services to manage, monitor and configure beacons.Proximity beacons $5 each, but not Eddystone compat?. ![]()
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