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bluetoothbluetooth-lowenergyiotgatewayibmwearables

Maximum number of BLE sensors that could be connected to a BLE gateway at a given instant?


I have this doubt. For example, I have a Smart Wrist Band (measures pulse, body temp), a Smart Gear/Watch (to display text alerts, control calls) and a Bluetooth headset. I need all the three to communicate with my mobile phone at the same given instant.

Is it possible to achieve the same ?

What are the challenges involved if I need to develop an application on my own if I had to achieve the above possibilities ?

Your help is highly appreciated.

Note: - BLE has star-based network topology and maximum devices per Piconet is 8 including the Master - Please help me in understanding/visualizing the above theory that I learnt.

Thanks.


Solution

  • The Bluetooth Classic has a limitation of 7 slave devices in a piconet and they are time and hop synchronized to the master ( ie master and slaves share a common physical channel and it is not possible to address more than seven slaves for a master when in Active mode). In BLE each connection from a master to a slave operates in an independent physical channel( ie LE slaves does not share a common physical channel with the master), hence there is no limitation imposed by the Specification except as specified by the Connection interval and slave latency rules ( Note that individual bluetooth controller manufacturers may decide to limit the number of connections depending on the practical bandwidth limitation). please see the Bluetooth Classic vs Bluetooth Low energy Topology below. Bluetooth classic Topology BLE topology

    Is it possible to achieve the multiple sensors ( BLE) and Headset (BT classic) connected to mobile? Yes it is very much possible, except that there are some BT4.0 controllers which doesn't allow LE advertisement while connected to another BLE device. please check the known limitations in a particular bluetooth controller.