Provided is a piezoelectric ceramic composition capable of being sintered at low temperatures and in a low-oxygen reductive atmosphere and capable of attaining a sufficient displacement even at high voltages of 1 kVmm or more. The method begins by generating a login field in response to receiving an authentication request from an end user. At each site, the system senses reentrant circuits causing the atrial fibrillation. High measurement precision, low-manufacturing costs, and other benefits are provided by the present inventions. The number of times the reference scale current is replicated is based on the fixed capacitance that is switched-in to the LC circuit and therefore the frequency band of the PLL. The methods comprise the steps of estimating an excess amount of power used by the first transceiver for transmitting the signal, reducing the first transceiver’s power use by the excess amount of power to a reduced power level, and transmitting the signal from the first transceiver using the reduced power level.