LPM2100 mg NB Module Hardware User Guide
Shanghai Yuge Information Technology Co., Ltd.
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When the module is in the PSM mode, related activities such as searching for cell
messages, cell reselection, and connecting to the network are turned off. However, the T3412
timer continues to work.
There are two ways for the module to exit the PSM mode: one data terminal device
actively sends data wake-up, and the other is when the T3412 timer expires, the TAU starts,
and the module exits the PSM.
Figure 3-13 PSM power saving technology
3.6.2 DRX
The DRX cycle is short (1.28s, 2.56s, 5.12s, or 10.24s is determined by the carrier
network side). The downlink service is considered to be reachable at any time with a small
delay. The module will detect whether there is a downlink service arrival, which is suitable for
services with high latency requirements. Module equipment generally adopts the way of
power supply, such as street light business.
Figure 3-14 DRX power saving technology
3.6.3 eDRX
During each eDRX cycle, there is a Paging Time Window (PTW). The terminal listens to
the paging channel in the PTW according to the DRX cycle (the DRX cycle time is short, and
the terminal can be considered to be not sleeping and always reachable). Data, the rest of the
terminal is in a sleep state.
In eDRX mode, the terminal device can be considered as reachable at any time, but the
delay is large. The delay depends on the eDRX cycle configuration, which can balance the
low power consumption and the delay. Such as remote shutdown of the gas business.
