Hi, I am using the BLE_EddystoneBeacon_Service of mbed on a nrf51-Dk board. Using the original setup of the Eddystone the advertising interval must be 1000 msec = 1 sec. With this the power cosumption on nrf51-DK is 1.23 mA. So, the lifetime of CR2032 (240 mAh) is the 195 hours = 8.1 days aprox. With defaul_beacon_period_msec = 5000 the power consumtion was of 1.16 mA. 1- How can I improve the battery lifetime? 2- Which are the criteria to move the parameters AdvPowerLevels , radioPowerLevels and startBeaconService? Original setup of the Eddystone: file --> EddystoneService.h static const uint32_t DEFAULT_CONFIG_PERIOD_MSEC = 1000; static const uint16_t DEFAULT_BEACON_PERIOD_MSEC = 1000; file --> main.cpp /* Initialize a EddystoneBeaconConfig service providing config params, default URI, and power levels. */ // Values for ADV packets related to firmware levels, calibrated based on measured values at 1m static const PowerLevels_t defaultAdvPowerLevels = {-47, -33, -21, -13}; // Values for radio power levels, provided by manufacturer. static const PowerLevels_t radioPowerLevels = {-30, -16, -4, 4}; eddyServicePtr->startBeaconService(5, 5, 5); Thanks and best regards, Leonardo