oad Indoor 10 dB Indoor 20 dB Indoor 30 dB LTE-M, Application 1 LTE-M, Application 2 NB-IoT, Application 1 NB-IoT, Application 2 Figure 14.16 Number of supported loT devices per sector. groups applying the two applications. The session delay includes payload transfer, synchronization time overhead, and overhead due to RRC signaling. We note the delay is lower in a good signal than in a deep indoor environment due to the higher data rate. LTE-M shows a lower delay than NB-IoT because of the higher data rate. The delay for LTE-M is less than 300 ms and for NB-IoT approximately 1 S in a good signal environment. The delay with LTE-M and NB-IoT is similar with 20-30 dB indoor penetration loss, and the value is 1-4 S. Application 2 shows slightly lower delays than application 1 because of less data transmission. For more details, see [2]. Next, the number of supported IoT users per sector is calculated, based on the path loss values and on the estimated delays. LTE-M supports 5-8 times more users than NB-IoT, which is expected because six times more PRBs are allocated for LTE-M. The capacity in good signal areas is more than 200 000 users per sector with LTE-M for application 1 and even more than 1 million users per sector for application 2. That is an impressive capacity. NB-IoT can support more than 50 000 users per sector. Dense networks tend to have more than 30-50 sectors per km², which indicates that NB-IoT can support even 1 million IoT devices per km². If all users experience 20-30 dB indoor penetration loss, the capacity is lower because each transaction occupies more time and resources (Figure 14.16). LTE IoT capacity can be further enhanced by allocation of more resources for IoT transmission with more PRBs and more frequencies. Power Saving Features In order to achieve a 10-year battery life for IoT modules, the power saving sleep mode must be efficiently utilized, which means the UE should wake up only very seldom to receive paging messages. Release 12 provides PSM, where the UE wakes up to perform 14.8 Po