Critical power analysis for control path of a CAT-M based edge device

Abstract

LTE Machine Type Communication Category M1 [LTE CAT M (or M1)] is a 3GPP Low Power Wide Area Network most suitable for IoT devices that need low data rates, deep coverage, low-cost, and, most importantly, power-efficient devices. As the number of IoT system devices (called things) is growing massively, there is a shift needed from the traditional LTE network to these low power networks. Power consumption should be minimum for all stages of device functionality to keep the devices working for longest possible time. We performed a power consumption analysis of CAT-M technology under various control path scenarios using a standard CAT-M modem. Due to the absence of a live CAT-M network in India, we use a network simulator to emulate live network scenario by varying network parameters. We measured the power consumed by the CAT-M modem using a standard tool and present simulation results of a variety of network configurable parameters allowed by 3GPP. These parameters are configurable both in scope of user equipment and network deployment. This paper covers some important power measurements related to Power Saving Mode (PSM), extended Discontinuous Reception Mode (eDRX), Uplink Transmission Power, Channel Repetition, Bandwidth and Sub-carrier Spacing. Data path (user payload) considerations are not scope of this document. By the end of the paper, we identified the impact of each parameter on the performance of the CAT-M modem.