Frequency assigned information gathering method for motion-capture in wireless sensor networks

In this paper, we present a novel information gathering method based on frequency assigned information for wireless sensor networks targeting motion-capture. Traditional information gathering method based on exchanging multiple data packets requires a long duration when it uses multi-dimensional information from many sensor nodes. In the proposed method, each node maps the data sensed through a three-dimensional accelerator onto the subcarriers of the OFDM signals. Moreover, dimension identifying information is used for the order of the subcarriers indicating three-dimensional acceleration converted to a subcarrier-frequency of OFDM signals. Finally, each node is assigned to the time slots. Then, all sensor nodes send OFDM signals according to the assigned subcarrier-frequency and timeslots. The sink node receives the sent OFDM signals and estimates the correct information from frequency mapping and timing of the received signals. By using the proposed method, we can gather high precision sensing multi-dimensional information with an arbitrary node number in a short time.