Characteristics of transmission carrier in a new wire communication system by the use of high-ripple DC-DC converter

In the newly proposed wire communication system, converters are utilized as transmitter as well as power supply. Signal transmission is performed by the use of output voltage ripple. At transmission of a message, the ripple is intentionally increased and modulated by the signal. In this paper, the output filter capacitor of the dc-dc converter is changed according to reception or transmission. At reception, output voltage ripple is made small enough. At transmission, output voltage ripple is enlarged and used as carrier. Output voltage ripple of a buck-type dc-dc converter having small capacitance of the output capacitor becomes almost sinusoidal, when the duty ratio is 0.5. From view point of impedance matching, the output impedance is investigated. Magnitude of ripple voltage is varied by several reasons. Therefore, digital FM (Frequency Modulation), for example, FSK (Frequency-Shift Keying) can be recommended.