Introduction A low power OOK transceiver for short-range wireless sensor networks (e.g. body area networks) is developed in this paper. The target receiver (RX) sensitivity and transmitter (TX) output power is -55dBm and -20dBm, respectively, assuming -25dB propagation loss at the 1-m communication distance and -5dB x 2 loss at TX/RX antennas. The target power consumption is 50μW at 1Mbps. In order to reduce the power, (1) sampling circuits are used instead of continuous analog circuits, (2) the power supply voltage (VDD) is reduced to 0.5V, (3) the RX input is directly sampled without LNA, because high sensitivity is not required for the 1-m communication, (4) low career frequency of 315MHz instead of 2.4GHz is used to reduce the required bandwidth of the sampler, (5) a career-frequency-free (CFF) intermittent sampling (IS) is newly proposed to reduce the number of sampling, thereby reducing the power of the sampler to 1/315 of that of the conventional continuous sampling.