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I have some Bluvision Beeks beacons equipped with temperature sensors. I can adjust their transmit powers. I am wondering if setting a higher transmit power for a particular beacon will result in a better sensor reading than if the beacon were set to a lower transmit power in general. Or is higher transmit power only provided in order to achieve a longer range?

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    Can you explain the reasoning behind your question? You realise that the transmission is digital, with error detection, right?
    – Sean Houlihane
    Apr 12, 2017 at 16:58
  • @SeanHoulihane Because I wasn't sure that digital transmission would prevent distortion of the reading by the channel. Thanks, you answered my question!
    – Undertherainbow
    Apr 12, 2017 at 17:11

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Bluetooth (and pretty much every other transmission protocol in contrast to sensors like radar) are based on digital protocols. This means that the signals are both binary, and protected by error detection/correction codes.

So long as the signal is strong enough that there are only a few errors in any one packet, the resulting sensor reading which is sent will not change. Specifically in the case of BLE, there is no error correction overhead in the packets, just a CRC. Any received packet which is errored will not be acknowledged. This causes the packet to be re-sent (so increasing latency as a trade-off for improved typical throughput). (from here, as per @Aurora0001)

More power can sometimes cause problems, where you have lots of sensors sharing the same band.

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    But if there are errors, will the packet be dropped and re-transmitted?
    – Undertherainbow
    Apr 13, 2017 at 11:19
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    @Undertherainbow Yes. According to this BLE uses Stop-and-wait ARQ—"Typically the transmitter adds a redundancy check number to the end of each frame. The receiver uses the redundancy check number to check for possible damage. If the receiver sees that the frame is good, it sends an ACK. If the receiver sees that the frame is damaged, the receiver discards it and does not send an ACK—pretending that the frame was completely lost, not merely damaged."
    – Aurora0001
    Apr 13, 2017 at 11:32
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    @Aurora0001 The linked page has very useful information I wasn't able to find elsewhere. Thank you so much.
    – Undertherainbow
    Apr 13, 2017 at 13:25

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