All modes support battery operated devices. Even mode N using high power (500 mW) at 169 MHz can be used for smart meters with 15-20 years battery lifetime, as the number of transmissions per day is normally limited to less than 10. In drive-by or walk-by systems where transmissions are much more frequent we recommend to use mode T or mode C. The mode C use NRZ coding, and with frame format B, it will give the shortest transmissions and hence the lowest power consumption. You may also use the AES-128-CTR mode and compact frame format to further reduce the application layer data.
Last Update: August 8, 2017