3GPP Release-16 Preconfigured Uplink Resources for LTE-M and NB-IoT

Since Release 13, the Long Term Evolution (LTE) of the 3rd Generation Partnership Project (3GPP), Narrowband Internet of Things (NB-IoT), and LTE for machine-type communications (LTE-M) provide wide-area connectivity for IoT. In subsequent releases, their basic functionalities evolved to support higher data rates, enhanced mobility, and power saving features. In Release 16, Preconfigured Uplink Resources (PUR) introduce the possibility to assign radio resources to a user equipment (UE) in advance for transmission of uplink data without the need of connection setup. In this article we show that the UE power saving gain from PUR compared to existing features is largest if data transmissions are relatively frequent and payloads are small enough to be transmitted in a single shot. For example, with periodicity of 30 s, 50 bytes payload, and 43 min extended discontinuous reception (eDRX) cycle, the gain for PUR compared to early data transmission (EDT) ranges from 50 percent in good coverage to 7 percent in deep coverage.