Highlights of the report include the following:
Thanks
This study was done in collaboration with the H2020 EU TRIANGLE Project and the Connectivity Services Section at Aalborg University. TRIANGLE performed tests on the author's behalf, leveraging its lab facilities in Europe. The author takes full responsibility for the analysis of the data provided in the report.
Methodology
The author tested Cat M1 and Cat NB1 modules and devices leveraging Keysight Technologies test equipment. By measuring the voltage and current with a high sampling rate and with very precise accuracy the author was able to estimate the battery life of the devices under test. Additionally, we were able to allocate the energy budget to each IoT state (PSM, DRX, Synch,etc.).
The Scope
The author included 3 radio conditions (Good, Robust and Extreme), four reporting cycles (2 hours to monthly) and nine data payloads (2 bits to 1,600 bits). Results in the report slice and dice the results in multiple ways to show the relative impact of each primary assumption in the scenario. In addition to showing absolute results, we provide relative analysis to quantify the percentage impact of modifying each assumption.
The Results
10-year battery life is feasible with many scenarios - in fact, we observed multiple scenarios in which the battery life exceeded the life expectancy of a human residing in the US circa 1800. However, in other cases, the estimated battery life fell well short of the 3GPP target threshold of 10 years. Furthermore, the analysis excludes ancillary components that an IoT device will likely need and which could have a very meaningful impact on battery life.
More to Come
Later this year the author hopes to take the study to the field, now that several US operators have launched commercial services using NB-IoT and eMTC. In the interim, there will be more 5G studies, including more millimetre-wave, as well as 2.5 GHz.
Table of Contents
1. Executive Summary
2. Key Observations
3. A Quick Introduction to LTE-M and NB-IoT Power Saving Features
4. Cat NB1 Power Measurement Results and Analysis
4.1 Cat NB1 Power Measurement Results and Analysis
4.2 Cat NB1 Battery Life Estimates and Analysis
4.3 Cat NB1 Energy Budget Analysis
5. Cat M1 Power Measurement Results and Analysis
5.1 Cat M1 Battery Life Estimates and Analysis
5.2 Cat NB1 and Cat M1 Comparative Analysis
6. Test Methodology
7. Final Thoughts
8. Appendix
Index of Figures & Tables
Table 1. Cat M1 and Cat NB1 Modules and Devices
Table 2. Scope of the Study
Figure 1. 3GPP IoT Transition States
Figure 2. DRX and C-DRX Idle Mode Power Requirements
Figure 3. DRX Active Listening and Synchronization Times
Figure 4. DRX Active Listening and Synchronization Energy Requirements
Figure 5. C-DRX Active Listening and Synchronization Times
Figure 6. C-DRX Active Listening and Synchronization Energy Requirements
Figure 7. PSM Power Requirements
Figure 8. Receive Mode Power Requirements
Figure 9. TX Transmission Power versus TX Power Consumption
Figure 10. Estimated Battery Life – 24-hour reporting with good conditions and varying data payloads
Figure 11. Estimated Battery Life – 24-hour reporting with robust conditions and varying data payloads
Figure 12. Estimated Battery Life – 24-hour reporting with extreme conditions and varying data payloads
Figure 13. Estimated Battery Life – 2-hour reporting with robust conditions and varying data payloads
Figure 14. Estimated Battery Life – 24-hour reporting with robust conditions and varying data payloads
Figure 15. Estimated Battery Life – Monthly reporting with robust conditions and varying data payloads
Figure 16. Estimated Battery Life – 2-hour reporting with 10-byte payload and varying network conditions
Figure 17. Estimated Battery Life – 2-hour reporting with 100-byte payload and varying network conditions
Figure 18. Estimated Battery Life – 2-hour reporting with 500-byte payload and varying network conditions
Figure 19. BC95-B20 Performance – Extreme Conditions
Figure 20. SARA-N211 Performance – Extreme Conditions
Figure 21. SARA-R410M Performance – Extreme Conditions
Figure 22. Energy Budget – 10 Bytes @ 2-hour reporting with good conditions
Figure 23. Energy Budget – 10 Bytes @ 2-hour reporting with extreme conditions
Figure 24. Energy Budget – 500 Bytes @ 24-hour reporting with good conditions
Figure 25. Energy Budget – 500 Bytes @ 24-hour reporting with extreme conditions
Figure 26. Energy Budget – 100 Bytes @ 24-hour and monthly reporting with good conditions
Figure 27. Energy Budget – 1600 Bytes @ 24-hour and monthly reporting with extreme conditions
Figure 28. DRX and C-DRX Idle Mode Power Requirements
Figure 29. DRX Active Listening and Synchronization Times
Figure 30. DRX Active Listening and Synchronization Energy Requirements
Figure 31. C-DRX Active Listening and Synchronization Times
Figure 32. C-DRX Active Listening and Synchronization Energy Requirements
Figure 33. PSM Power Requirements
Figure 34. Receive Mode Power Requirements
Figure 35. TX Transmission Power versus TX Power Consumption
Figure 36. Estimated Battery Life – 24-hour reporting with good conditions and varying payloads
Figure 37. Estimated Battery Life – 24-hour reporting with robust conditions and varying payloads
Figure 38. Estimated Battery Life – 2-hour reporting with robust conditions and varying payloads
Figure 39. Energy Budget – 500 Bytes @ 24-hour reporting with good conditions
Figure 40. Energy Budget – 500 Bytes @ 24-hour reporting with robust conditions
Figure 41. SARA 410-2M Estimated Battery Life – 2-hour reporting period with varying payloads and network conditions (LTE-M1 versus LTE-NB1)
Figure 42. SARA 410-2M Estimated Battery Life – 24-hour reporting period with varying payloads and network conditions (LTE-M1 versus LTE-NB1)
Figure 43. NL-SW-LTE-QBG96 Estimated Battery Life – 2-hour reporting period with varying payloads and network conditions (LTE-M1 versus LTE-NB1)
Figure 44. NL-SW-LTE-QBG96 Estimated Battery Life – 24-hour reporting period with varying payloads and network conditions (LTE-M1 versus LTE-NB1)
Figure 44. SARA R410-2M Estimated Battery Life – 1-month reporting period with varying payloads and network conditions (LTE-M1 versus LTE-NB1)
Figure 45. NL-SW-LTE-QBG96 Estimated Battery Life – 1-month reporting period with varying payloads and network conditions (LTE-M1 versus LTE-NB1)
Figure 46. SARA R410-2M NB1 and M1 Energy Budget with varying conditions – 2-hour reporting cycle
Figure 47. NL-SW-LTE-QBG96 NB1 and M1 Energy Budget with varying conditions – 2-hour reporting cycle
Figure 48. Test Setup
Table 3. N6705 Measurement Accuracy
Figure 49. Power Saving Mode (PSM) Cycle Power Requirements
Figure 50. Quectel BC95-B20 Active Period with Different Repetitions
Table 4. Network and Device Parameters – NB-IoT
Table 5. Network and Device Parameters - LTE-M
Figure 51. Estimated Battery Life – 10-byte payload and robust network conditions with varying reporting periods
Figure 52. Estimated Battery Life – 100-byte payload and robust network conditions with varying reporting periods
Figure 53. Estimated Battery Life – 1000-byte payload and robust network conditions with varying reporting periods
Figure 54. BC95-B20 Performance – Good Conditions
Figure 55. SARA-N211 Performance – Good Conditions
Figure 56. SARA-R410M Performance – Good Conditions
Figure 57. BC95-B20 Performance – Robust Conditions
Figure 58. SARA-N211 Performance – Robust Conditions
Figure 59. SARA-R410M Performance – Robust Conditions
Figure 60. Energy Budget – 10 Bytes @ 24-hour and monthly reporting with good conditions
Figure 61. Energy Budget – 10 Bytes @ 24-hour and monthly reporting with extreme conditions
Figure 62. Estimated Battery Life – 1-week reporting with robust conditions and varying payloads
Figure 63. Estimated Battery Life – 1-month reporting with good conditions and varying payloads
Figure 64. Energy Budget – 10 Bytes @ 2-hour reporting with good conditions
Figure 65. Energy Budget – 10 Bytes @ 2-hour reporting with robust conditions
Table 6. Cat NB1 Power Consumption Per State
Table 7. Estimated Cat NB1 Battery Life
Table 8. Cat M1 Power Consumption Per State
Table 9. Estimated Cat M1 Battery Life
