... and embedded real time multitasking RTOS operation system;2.2 Being able to support various type channel of communication, such as GPRS, CDMA,PSTN, SMS and ... locally or remotely, support online upgrade.2.5 A concentrator can be collecting and management data of power meter ... high voltage, strong magnetic field, strong static, and thunder, also with wide range of temperature. AMR System,GPRS AMR System