A Digital Radio-Frequency Condenser Microphone with Amplitude Modulation

A novel digital radio-frequency (RF) condenser microphone system is proposed. Condenser microphones using the audio-frequency (AF) implementation method basically suffer from their high impedance sensor circuitry. The RF implementation method solves this problem. In RF condenser microphones, the inherent impedance can be lowered leading to superior noise performances. Since state of the art RF microphones are still entirely analog, a digital approach is presented which can further increase the demodulation linearity and can circumvent the 1/f noise as well as additional analog disadvantages.