Cellular IoT Device Battery Life Extension via Dynamic Power Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery-powered devices in utility and IoT applications face high power consumption when using cellular networks, leading to short battery life and inconvenient replacement schedules.
Innovation Solution
Adaptation of cellular network category M (NB1) for battery-powered devices, utilizing techniques such as adjusting transmit power levels, reporting schedules, and retry counts, along with received signal strength indicators (RSSI), to extend battery life and synchronize replacement times with nearby devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If battery-powered devices use cellular networks for data reporting, then data transmission capability is improved, but power consumption increases and battery life decreases
Solution Approach 1:
The patent implements dynamic adjustment of transmission power levels based on signal conditions. The device monitors received signal strength indicators (RSSI) and adapts transmit power accordingly, using higher power only when necessary for reliable transmission. This dynamic approach maintains data transmission reliability while minimizing average power consumption compared to fixed high-power transmission.
Solution Approach 2:
The system changes multiple operational parameters including transmit power level, reporting interval duration, and number of retry attempts. By adjusting these parameters based on battery status and signal conditions, the system optimizes the balance between maintaining reliable data transmission and conserving battery power throughout the device's operational life.
2Reliability
If transmission power is increased to ensure reliable data delivery, then data transmission reliability is improved, but battery life decreases
Solution Approach 1:
The device employs feedback mechanisms by monitoring RSSI values from the cellular network and using this information to adjust transmit power levels. This closed-loop control ensures that transmission power is increased only when signal conditions deteriorate, maintaining reliable data delivery while avoiding unnecessary high-power transmission that would drain the battery prematurely.
Solution Approach 2:
The system uses partial action by transmitting at minimum necessary power levels rather than consistently using maximum power. It applies excessive action selectively by increasing power only when signal conditions require it for reliable transmission, thus balancing reliability requirements with battery conservation throughout operational periods.
3Loss of information
If reporting frequency is increased to improve data freshness, then data quality is improved, but power consumption increases
Solution Approach 1:
The reporting interval is dynamically adjusted based on battery status and data urgency. When battery charge is high, the system increases reporting frequency to provide fresher data. When battery charge decreases, the system extends reporting intervals to conserve power, accepting reduced data freshness as necessary to maintain operational life.
Solution Approach 2:
The system implements periodic reporting with variable intervals rather than continuous transmission. By strategically spacing reporting events based on battery status and network conditions, the system maintains acceptable data freshness while minimizing the total number of transmissions and associated power consumption.
4Reliability
If retry attempts are increased to ensure successful transmission, then data delivery reliability is improved, but power consumption increases
Solution Approach 1:
The system applies partial action by limiting the number of retry attempts to a reasonable threshold rather than attempting unlimited retries. This approach ensures adequate data delivery reliability for normal conditions while avoiding excessive power consumption from repeated transmission failures, particularly when signal conditions are poor and additional retries are unlikely to succeed.
Data Source
AI summary
Techniques for managing battery powered devices in a cellular network are described herein. In some instances, a receiving device, such as a data collector, may receive transmissions from a network endpoint, such as a utility meter. The messages may contain an indication of a power level used in the transmission. The receiving device may estimate a battery end-of-life date of the network endpoint, based at least in part on a known reporting schedule of the endpoint and the power level used in transmissions. The receiving device or the endpoint may revise the reporting schedule to modify the battery end-of-life date. In addition to modification of the reporting schedule, the endpoint power of transmission can be modified, based on RSSI and/or a transmission retry count.