PyGate - Temperature and power consumption

[kodarn]

Hi guys!

I have the following setup:

• PyGate board powered using the onboard USB-C interface
• GPy running the v1.20.2.rc10 firmware (as of 2020-07-01)
• Two external antennas (LoRa & WiFi)
• The example script from the documentation (https://docs.pycom.io/tutorials/pygate/) uploaded to the GPy.

This setup seems to be generating quite a lot of heat/high temperatures. Is this to be expected?

When looking at the power consumption on idle usage (that is, system up and running but no LoRa clients connected), the system consumes 0.36 amps. (i.e. 0.36 amps * 5 volt = 1.8 watt). Is this also to be expected?

[mxklt]

@Clemens @kodarn have a look at my repo :)

https://github.com/maxklt/lte-pygate

[kodarn]

@Clemens I have only used the WiFi part of the GPy so far. I haven't seen any examples using the LTE-M/NBIoT features. Would also be interested in that :-)

[Clemens]

@kodarn do you use the GPy as WiFi gateway or did you the code modification for using LTE on the GPy? I would be interested on code für the PyGate with GPy as LTE-M or NBIoT gateway. Is there any code around?

[rcolistete]

It would be interesting to measure the current consumption using WiPy 3 (= less power).

[jcaron]

@kodarn a few things to remember:

• a gateway does not actually know if there are any clients. A client may have joined through a different gateway but still have messages received by this one. Even if there are no clients at the network level, gateways would still need to listen for join requests.

• a gateway is thus always listening on all relevant channels, for all relevant data rates (bandwidth + spread factor combinations).

• a lot of this is actually done in software (digital signal processing) rather than hardware.

The end result is that even though LoRaWAN end devices can achieve very low power, this has never been a goal for LoRaWAN gateways, and in practice they are indeed rather power-hungry.

[robert-hh]

@kodarn These figures do not look excessive. A gateway has always to be up and ready to handle messages, which may come in at any time. LoRaWAN has not the model of connections. Each message uplink and possible downlink is independent from others.
Edit: A board similar to PyGate, the IC880a is specified at 276-433mA, and to that you have to add the current consumption of the GPY, which is 50-80 mA in operation w/o WiFi.