Data Rate & Throughput



  • In my experiment, I am sending some number of bytes every second and record the packets received at the end side.

    Up till 200metres I receive 60 packets in 80 seconds but at 300 metres I receive the same 60 packets in 105 seconds. Clearly this explains that as distance increases your data rate will be lesser, but in terms of throughput can I say that I lost 7 packets -- I observed that there were only 53 packets received within the 80 second time frame as earlier. Does this mean packet loss? Or do I have to go up till some distance where I receive sufficiently low or zero packets ? Can someone throw some light on this?



  • As the distance increases, the transmission - reception time increases. This results in increases bit error rate and reduced throughput. The observation made by you is as per expectations.



  • @eric73 thanks. I am in the US range. I have not specified SF so i guess it will be the default.



  • @snehasg96 Unless you implemented some protocol exchange between transmitter and receiver, data rates will not be changed. The transmitter will send packets at the set data rate. So most likely some packets go lost. You should be able to tell by e.g. adding a sequence number in the payload.



  • @snehasg96 Region (EU,US)? antenna gain ? SF used ?
    (If you dont set it up its seem that SF7 is used by default, with this SF i can reach 300m range in free field with a tx power at 2db)
    A lot of parameters is used in lora, with SF12 and antenna 2dB you can achieve 15km communiaction range but with more than 1 sec time on air for each frame(so we can only send 36 frames/hours to be inside regulation law). And in US you cannot use SF12 (if i remenber correctly), with lower SF shorter time on air so we can send more frame (but for smaller distance).
    On RX side you can use SNR and RSSI value to evaluate your link quality.



  • @bmarkus It is LoRa RAW. Sorry for not being precise.



  • @snehasg96 said in Data Rate & Throughput:

    In my experiment, I am sending some number of bytes every second and record the packets received at the end side.

    Up till 200metres I receive 60 packets in 80 seconds but at 300 metres I receive the same 60 packets in 105 seconds. Clearly this explains that as distance increases your data rate will be lesser, but in terms of throughput can I say that I lost 7 packets -- I observed that there were only 53 packets received within the 80 second time frame as earlier. Does this mean packet loss? Or do I have to go up till some distance where I receive sufficiently low or zero packets ? Can someone throw some light on this?

    Is it Wifi, NB-IoT, LoRa RAW, LoRaWAN, ???


 

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