Acoustic wave communication apparatus and method
US6122312A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 19, 1999 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | Nov 19, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/1672
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An apparatus for accurately transmitting and receiving acoustic waves indoors is provided. The apparatus contains a microphone, a speaker, a processing circuit, a first amplifier, a second amplifier, and a power control circuit. The microphone converts an input acoustic wave into an electric signal, and the speaker generates an output acoustic wave based on input data. The processing circuit processes the electric signal to produce processed data and outputs the input data to drive the speaker. The first amplifier receives a power signal and detects if a starting signal is contained in the electric signal output from the speaker. Then, the amplifier outputs a first detection signal when the starting signal is detected and outputs the power signal when the first detection signal is output. The second amplifier receives the power signal from the first amplifier and detects if a non-starting signal is contained in the electric signal when the starting signal is detected. The amplifier outputs a second detection signal when the non-starting signal is detected. The power control circuit supplies the power signal to the processing circuit when the first and second detection signals have …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.