CPC H03B 5/1243 (2013.01) [H03B 5/1206 (2013.01); H03B 5/30 (2013.01)] | 25 Claims |
1. A demodulation signal generator, coupled to an air-pulse generator, the demodulation signal generator comprising:
a first node coupled to a first flap and a second node coupled to a second flap; and
a resonance circuit, coupled to the first and second nodes, configured to produce a first demodulation signal on the first node and a second demodulation signal on the second node;
wherein the air-pulse generator comprises a film structure, the film structure comprises a flap pair, the flap pair comprises the first flap and the second flap;
wherein the resonance circuit and the flap pair co-perform a resonance operation, such that the first demodulation signal and the second demodulation signal are generated via the co-performed resonance operation;
wherein the first and the second demodulation signals have opposite polarity;
wherein the first flap receives the first demodulation signal and the second flap receives the second demodulation signal, such that the flap pair performs a differential movement;
wherein the differential movement is configured to form a virtual valve or an opening to perform a demodulation operation on a modulated air pressure variation generated by the film structure;
wherein the virtual valve is closed corresponding to a period within a first transition time of the first demodulation signal and a second transition time of the second demodulation signal.
|