LoRa/LoRaWAN tutorial 23: ETSI Duty Cycles, TTN Fair Access Policy and Transmit Time Interval
12.8 هزار بار بازدید -
6 سال پیش
-
If you like this video
If you like this video and want to support me, go this page for my donation Paypal or crypto addresses:
mobilefish
This is part 23 of the LoRa/LoRaWAN tutorial.
In this video series different topics will be explained which will help you to understand LoRa/LoRaWAN.
It is recommended to watch each video sequentially as I may refer to certain LoRa/LoRaWAN topics explained earlier.
In tutorial 22 I transmitted the message "Hello, world!” every 60 seconds using the sketch ttn-otaa-mydemo.
At the end of that video I asked the question:
Do I comply with the ETSI duty cycles and The Things Network Fair Access Policy if I keep running the sketch for a day?
In this tutorial I will answer that question and I also will explain what the transmission time interval is and how it is calculated.
In this tutorial I will only focus on the ETSI duty cycles and in particular the duty cycles which applies in Europe.
Please do your own research and check which duty cycles regulations, if any, applies to your country.
In Tutorial 11, I have explained that ETSI divides the 863-870 MHz band into 5 sub-bands: G, G1, G2, G3 and G4 and each sub band has different constraints in terms of EIRP, duty cycle and channel bandwidth.
In Tutorial 22 I have demonstrated how to transmit the message “Hello, world!” every 60 seconds.
The metadata displayed in TTN console during the demonstration can be found here:
https://www.mobilefish.com/download/l...
As mentioned in tutorial 11, an end device changes channel in a pseudo-random fashion for every transmission.
In Europe for uplink transmissions 8 different frequencies are used.
In Europe, for all 8 frequencies, the duty cycle is 1%
This means, the total allowed uplink Time on Air is (86400 x 1% =) 864 sec per day, per device.
The Things Network Fair Access Policy is there to make sure that the community network is not abused by large deployments and applies to all of the community network.
More information about TTN Fair Access Policy can be found at:
https://www.thethingsnetwork.org/docs...
The TTN Fair Access Policy limits the data each end-device can send, by allowing:
- An average of 30 seconds uplink Time on Air, per day, per device.
- At most 10 downlink messages per day, including the ACKs for confirmed uplinks.
Compared to the ETSI duty cycles of 1%, TTN Fair Access Policy is more restrictive because it only allows an average of 30 seconds uplink Time on Air, per day, per device.
This is equivalent to a duty cycle of 0.0347 %
A duty cycle is the fraction of one period in which a signal or system is active.
Example 1:
If duty cycle = 1% and ToA=0.05 sec
Tinterval = (ToA / DutyCycle) - ToA
Tinterval = (0.05 / 0.01) - 0.05 = 4.95 sec
Example 2:
If total uplink ToA = 30 sec per day, per device and ToA=0.05 sec
DutyCycle = 30 / 86400 = 0.00034722
Tinterval = (ToA / DutyCycle) - ToA
Tinterval = (0.05 / 0.00034722) - 0.05 = 143.95 sec
Question:
Do I comply with the ETSI duty cycles and The Things Network Fair Access Policy if I keep running the ttn-otaa-mydemo sketch for a day?
Note: In the sketch Tinterval (TX_INTERVAL) was set to 60 sec.
Answer:
I only need to focus on TTN Fair Access Policy because it is more restrictive.
TTN Fair Access Policy uses a total uplink ToA of 30 sec per day, per device
ToA=82.432 msec
DutyCycle = 30 / 86400 = 0.00034722
Tinterval = (ToA / DutyCycle) - ToA
Tinterval = (0.082432 / 0.00034722) - 0.082432
Tinterval = 237.32 sec
Yes, I will break the TTN Fair Access Policy.
In the ttn-otaa-mydemo sketch the transmit time interval (TX_INTERVAL) is set to 60 sec but it should be 238 sec.
The above mentioned calculated transmit time interval does not change as long if the payload length and data rate does not change.
Lets assume the following situation, my gateway went down and the nearest gateway my end device can send messages to is 5 km away.
Data rate = SF12BW125
Code Rate = 4/5
Payload length = 13 bytes (“Hello, world!”)
What is the new transmit time interval when using The Things Network?
Calculate the Time on Air:
https://www.loratools.nl/#/airtime
Calculated ToA = 1155.07 ms
Note:
The online Time on Air tool, shows: One message every 01:56 (mm:ss)
This is based on a duty cycle of 1%
TTN Fair Access Policy uses a total uplink ToA of 30 sec per day, per device
DutyCycle = 30 / 86400 = 0.00034722
Tinterval = (ToA / DutyCycle) - ToA
Tinterval = (1.15507 / 0.00034722) - 1.15507
Tinterval = 3325.47 sec = 55:25 (mm:ss)
Check out all my other LoRa/LoRaWAN tutorial videos:
LoRa/LoRaWAN tutorials
Subscribe to my YouTube channel:
@mobilefish
The presentation used in this video tutorial can be found at:
https://www.mobilefish.com/developer/...
#mobilefish #lora #lorawan
mobilefish
This is part 23 of the LoRa/LoRaWAN tutorial.
In this video series different topics will be explained which will help you to understand LoRa/LoRaWAN.
It is recommended to watch each video sequentially as I may refer to certain LoRa/LoRaWAN topics explained earlier.
In tutorial 22 I transmitted the message "Hello, world!” every 60 seconds using the sketch ttn-otaa-mydemo.
At the end of that video I asked the question:
Do I comply with the ETSI duty cycles and The Things Network Fair Access Policy if I keep running the sketch for a day?
In this tutorial I will answer that question and I also will explain what the transmission time interval is and how it is calculated.
In this tutorial I will only focus on the ETSI duty cycles and in particular the duty cycles which applies in Europe.
Please do your own research and check which duty cycles regulations, if any, applies to your country.
In Tutorial 11, I have explained that ETSI divides the 863-870 MHz band into 5 sub-bands: G, G1, G2, G3 and G4 and each sub band has different constraints in terms of EIRP, duty cycle and channel bandwidth.
In Tutorial 22 I have demonstrated how to transmit the message “Hello, world!” every 60 seconds.
The metadata displayed in TTN console during the demonstration can be found here:
https://www.mobilefish.com/download/l...
As mentioned in tutorial 11, an end device changes channel in a pseudo-random fashion for every transmission.
In Europe for uplink transmissions 8 different frequencies are used.
In Europe, for all 8 frequencies, the duty cycle is 1%
This means, the total allowed uplink Time on Air is (86400 x 1% =) 864 sec per day, per device.
The Things Network Fair Access Policy is there to make sure that the community network is not abused by large deployments and applies to all of the community network.
More information about TTN Fair Access Policy can be found at:
https://www.thethingsnetwork.org/docs...
The TTN Fair Access Policy limits the data each end-device can send, by allowing:
- An average of 30 seconds uplink Time on Air, per day, per device.
- At most 10 downlink messages per day, including the ACKs for confirmed uplinks.
Compared to the ETSI duty cycles of 1%, TTN Fair Access Policy is more restrictive because it only allows an average of 30 seconds uplink Time on Air, per day, per device.
This is equivalent to a duty cycle of 0.0347 %
A duty cycle is the fraction of one period in which a signal or system is active.
Example 1:
If duty cycle = 1% and ToA=0.05 sec
Tinterval = (ToA / DutyCycle) - ToA
Tinterval = (0.05 / 0.01) - 0.05 = 4.95 sec
Example 2:
If total uplink ToA = 30 sec per day, per device and ToA=0.05 sec
DutyCycle = 30 / 86400 = 0.00034722
Tinterval = (ToA / DutyCycle) - ToA
Tinterval = (0.05 / 0.00034722) - 0.05 = 143.95 sec
Question:
Do I comply with the ETSI duty cycles and The Things Network Fair Access Policy if I keep running the ttn-otaa-mydemo sketch for a day?
Note: In the sketch Tinterval (TX_INTERVAL) was set to 60 sec.
Answer:
I only need to focus on TTN Fair Access Policy because it is more restrictive.
TTN Fair Access Policy uses a total uplink ToA of 30 sec per day, per device
ToA=82.432 msec
DutyCycle = 30 / 86400 = 0.00034722
Tinterval = (ToA / DutyCycle) - ToA
Tinterval = (0.082432 / 0.00034722) - 0.082432
Tinterval = 237.32 sec
Yes, I will break the TTN Fair Access Policy.
In the ttn-otaa-mydemo sketch the transmit time interval (TX_INTERVAL) is set to 60 sec but it should be 238 sec.
The above mentioned calculated transmit time interval does not change as long if the payload length and data rate does not change.
Lets assume the following situation, my gateway went down and the nearest gateway my end device can send messages to is 5 km away.
Data rate = SF12BW125
Code Rate = 4/5
Payload length = 13 bytes (“Hello, world!”)
What is the new transmit time interval when using The Things Network?
Calculate the Time on Air:
https://www.loratools.nl/#/airtime
Calculated ToA = 1155.07 ms
Note:
The online Time on Air tool, shows: One message every 01:56 (mm:ss)
This is based on a duty cycle of 1%
TTN Fair Access Policy uses a total uplink ToA of 30 sec per day, per device
DutyCycle = 30 / 86400 = 0.00034722
Tinterval = (ToA / DutyCycle) - ToA
Tinterval = (1.15507 / 0.00034722) - 1.15507
Tinterval = 3325.47 sec = 55:25 (mm:ss)
Check out all my other LoRa/LoRaWAN tutorial videos:
LoRa/LoRaWAN tutorials
Subscribe to my YouTube channel:
@mobilefish
The presentation used in this video tutorial can be found at:
https://www.mobilefish.com/developer/...
#mobilefish #lora #lorawan
6 سال پیش
در تاریخ 1397/08/04 منتشر شده
است.
12,832
بـار بازدید شده