The 3GPP had standardized NB-IoT [3]-[5] in June 2016. It provides deep indoor and wide area coverage extension of 20dB over GSM. The NB-IOT network can support 50,000 users per cell and a battery life of more than ten years. The key problems of the NB-IoT network protocol are the coordination & communication between large number of IoT devices & the base station. Using the Beam Switching WPT (wireless power transfer) antenna array (BS-WPT antenna array) technology, the cell coverage could be separated into several partitions to wake up IoT devices within one partition of the cell to avoid the collision. The BS-WPT antenna array has been designed & analyzed in this paper for the polling protocol to solve the problem of communication and collision between 50,000 IoT devices per cell within the base station. ; 補正完畢