Multi-frequency transmission system for implanted hearing aids
US4611598A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1985 |
| Grant date | Sep 16, 1986 |
| Priority date | — |
| Expiry date | Apr 22, 2005 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/36036
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A multi-frequency transmission system for implanted hearing aid includes an external transmitting part and an encapsuled receiver part implantable into middle ear of the user. The transmitting part includes a microphone, a speech processor including a set of audio frequency band pass filters connected respectively via adjustable threshold switches to pulse shapers which release an audio frequency band only when an adjusted threshold level is exceeded. A plurality of high frequency transmitters is modulated by the signals from the pulse shapers. A pair of additional high frequency transmitters is controlled by the pulses from the speech processor to alternately transmit high frequency pulses corresponding to the polarity of the triggering pulses. A frequency channel selector is connected between the transmitters and the speech processor to activate simultaneously one of the transmitters from the bipolar high frequency stage and one of the amplitude modulated transmitters. The combined signal is applied to a transmitting coil and received by a receiver unit implanted in user's ear. The receiver includes a plurality of resonant circuits assigned to respective high frequency transmitte…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.