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    IoT, transfer "large" amount of data

    Hi,

    I am currently working on a wireless device that needs to transfer about 20Mo of data in a reasonable time (< 5 min) to a distant server. The device is controlled by a smartphone so the data can navigate through the phone before going to the distant server.

    I see 2 possibilities:
    - A dual BLE/3.0 bluetooth connection. BLE handles the communication with the device, while the "regular" BT handles the data transfer. Unfortunately BT (Low Energy or not) seems too slow for my needs.
    - BLE + Wifi. BLE handles communication device <-> phone, while the wifi sends the data directly to the server.

    Do you have any suggestion or comment?

    Thank you

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    Re: IoT, transfer "large" amount of data

    As I know BlueTooth is a LOW bandwidth protocol

    so the data goes from the 'device' to a phone then the server???

    For that amount of data in that time frame, I do not see a wireless solution Standard WiFi would be unable to do it.

    How about compressing the data in the device, first?



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    Re: IoT, transfer "large" amount of data

    Hi,

    What is:
    about 20Mo of data
    ?

    Klaus



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    Re: IoT, transfer "large" amount of data

    Quote Originally Posted by kam1787 View Post
    As I know BlueTooth is a LOW bandwidth protocol

    so the data goes from the 'device' to a phone then the server???

    For that amount of data in that time frame, I do not see a wireless solution Standard WiFi would be unable to do it.

    How about compressing the data in the device, first?
    This is why I think the second solution is better: Wifi handles the communication with the server (sends the large chunk of data), while BLE is used for the communication with the phone.

    Quote Originally Posted by KlausST View Post
    Hi,

    What is: ?

    Klaus
    I think your question is also related to compression.
    The signal is a chain of 16 bits integer coming from an ADC. Mostly concentrated in about half of the total range.
    The data is coming from an oximeter (infrared photo diode) and is a quite repetitive time series.



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    Re: IoT, transfer "large" amount of data

    Hi,

    I think your question is also related to compression.
    No. Not about compression.
    I really donīt know what "20Mo" means.

    Klaus



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    Re: IoT, transfer "large" amount of data

    Quote Originally Posted by KlausST View Post
    Hi,



    No. Not about compression.
    I really donīt know what "20Mo" means.

    Klaus
    Yep... Sorry it meant "Mega Octet" but I forgot I was writing in English and not French!

    So I meant 20 MByte :)



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    Re: IoT, transfer "large" amount of data

    Hi,

    Now I understand..

    20Mbyte in 5 min is
    20Mbyte in 300s is
    67kByte/s
    About 670kBaud

    Could be possible with bluetooth LE, but I don't know about overhead...

    Klaus



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    Re: IoT, transfer "large" amount of data

    Quote Originally Posted by KlausST View Post
    Hi,

    Now I understand..

    20Mbyte in 5 min is
    20Mbyte in 300s is
    67kByte/s
    About 670kBaud

    Could be possible with bluetooth LE, bug I don't know about overhead...

    Klaus
    Not sure about this.
    The RN4020 (BLE) has an OTA Throughput of 7kBit/s
    I looked into other non BLE module and they had about 40kBit/s maximum rate.
    Really far from what is required. But I would love to be proved wrong on this...



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    Re: IoT, transfer "large" amount of data

    Quote Originally Posted by KlausST View Post
    Hi,

    Now I understand..

    20Mbyte in 5 min is
    20Mbyte in 300s is
    67kByte/s
    About 670kBaud

    Could be possible with bluetooth LE, bug I don't know about overhead...

    Klaus
    From the wiki on bluetooth LE:
    Application throughput 0.7–2.1 Mbit/s (classic) 0.27 Mbit/s (smart/LE)

    It seems that LE has a rather low bar for application data throughput well below the 670KBaud desired. It might work with the classic.



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    Re: IoT, transfer "large" amount of data

    Quote Originally Posted by ads-ee View Post
    From the wiki on bluetooth LE:
    Application throughput 0.7–2.1 Mbit/s (classic) 0.27 Mbit/s (smart/LE)

    It seems that LE has a rather low bar for application data throughput well below the 670KBaud desired. It might work with the classic.
    Yes but this is the "theorical" throughput, not the real over the air throughput which is really lower.
    The classic is a few times faster than the BLE. And the BLE is <10kBit/sec



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    Re: IoT, transfer "large" amount of data

    what about just a 2fsk link in one of the ISM bands? Should be able to get 1 mbps at 200 feet.

    for instance, silicon labs chip using gfsk

    http://www.silabs.com/Support%20Docu...-DataSheet.pdf
    Last edited by biff44; 29th August 2016 at 23:49.



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