Restrict Range

[yash dave]

hi,

Is it possible to restrict range / rssi value upto certain range.?

I want to connect ble within 2 meter only. No device should connect after 2 meter.

kindly support.

[Daniel Wang]

Yes, it's possible to only allow device within a certain RSSI value to connect. Do some measurement with you device, and test what the RSSI is when your devices is 2m apart. This is done in e.g. Gazell, "Gazell only allows pairing when Host and Device are in close proximity to each other. The Received Signal Strength Indication (RSSI) is used on the Host side of the nRF51 so that only Devices residing close (<30 cm) to the Host will be allowed to pair". Here you set a RSSI threshold for when signal strength in RX packet power is high enough, for your device to accept the connection request. You can of course do this with BLE also.

[endnode]

Isn't that pretty loose security feature? Transmitting with higher signal strength to achieve better RSSI on receiver's side looks trivial. Even if it is not security but just user convenience/experience feature how you want to achieve it if you don't control HW on both sides of the link? Variations in Tx characteristics as well as receiver's sensitivity will kill the effect...