Batteryless 900-μs-latency FM transmitter powered by piezoelectric generator for wireless electronic drums

One problem with the plethora of electronic instruments in the music world today is all the wires and cables that need to be transported, plugged in, and managed. For an electronic drum set, the wires make setup complicated and look messy, and the difficulty of assembly and disassembly limits its use to one fixed place. A wireless system, on the other hand, would provide portability and greatly expand the range of venues where electronic drums could be used in place of acoustic ones. A batteryless self-powered wireless transmitter has been developed that sends a signal from a drum pad to a synthesizer. The power generated by a piezoelectric generator functions both as the "Play" signal for the synthesizer and as the power source for the wireless transmitter. A DC isolation technique based on a transformer and coupling capacitors provides efficient power division. The system employs direct FM modulation so that zero latency is theoretically supported in the radio transmission process. Experimental results for an electronic drum without any connecting wires fully demonstrated the feasibility of a self-powered wireless transmission system with a latency of 900 μs.