IoT Accelerator CAT-M Power Saving Mode interoperability
Mobile networks introduced some features, standardized by 3GPP, aimed to improve energy efficiency, in particular dedicated to low power cellular IoT devices. One of these is Power Saving Mode, PSM.
When PSM is enabled on device as well as on network side, the cellular modem on the device is allowed to go in “sleep state” with a very low energy consumption for a given time. The device battery life may last some years in this way.
Time to time the device will wake up either to send/receive some data or simply to re-state its registration with the mobile network. Such a behavior, mainly ruled by two timers, is negotiated with the cellular network and leads necessarily the device during the sleep time to become unreachable for the downlink traffic: PSM is therefore suitable for applications that are tolerant to delay and latency to communicate with the remote device.
The PSM principles tutorial explains an experiment with PSM and demonstrates its mechanisms between IoT Accelerator (network) and M5Stack IoT Base CAT-M module (device).
You can also download the M5Stack Source code and the relative guide.