US5319716A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wireless CD/automobile radio adapter
Assignee: Thomson Licensing SAS
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Filing: 1993-03-16
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Granted: 1994-06-07
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Expires: 2013-03-16
Abstract
Abstract This invention discloses a wireless compact disc stereo playback system for use in automobiles. An FM transmitter is employed which is connected at the output of a portable CD player, the FM transmitter thereby producing a stereo FM signal which is transmitted to be received by the automobile antenna. The automobile's FM system is tuned to play the output of the CD player through the FM radio system of the automobile. The output power of the FM transmitter and its bandwidth are selected so that the distance from the antenna to the FM transmitter will be sufficient to ensure effective sound production in standard automobiles and vans.
Inventors
- 👤 William T. McGreevy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:04
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/44; H04H20/46; H04H20/47; H04H20/48; H04B; H04B1/00; H04B1/02; H04B1/04
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
245 words
In combination, a wireless compact disc player/automobile radio adapter, an FM radio in an automobile and an antenna of said automobile connected to said FM radio, said adapter operating to couple radio frequency signals to said FM radio in said automobile through the antenna of the automobile, said adapter comprising a wireless radio frequency transmitter connected to receive as input signals the output of said compact disc player, said transmitter controlled to operate within the frequency range of an FM radio, said transmitter power operates below 250 microvolts per meter at three meters in the power range of unintentional power radiators, said transmitter to be used within said automobile and having sufficient power to generate a radio frequency signal which will be detected by the antenna of said automobile, said transmitter transmitting radio frequency signals which are detected by the antenna of the radio of the automobile, said adapter including said transmitter being portable and movable within said automobile without interruption of transmission of said radio frequency signals, said adapter operable to operate within said automobile when it is moving by coupling said radio frequency signal emanating from the transmitter to the antenna of the automobile, said transmitter being tunable by a passenger in the vehicle to a selected transmission frequency such that the FM radio of said automobile is tunable to said selected transmission frequency to enable the compact disc player to play through the antenna input to the FM radio of the automobile.
Claim 2
Dependent Claim
245 words
In combination, a wireless compact disc player/automobile radio adapter, an FM radio in an automobile and an antenna of said automobile connected to said FM radio, said adapter operating to couple radio frequency signals to said FM radio in said automobile through the antenna of the automobile, said adapter comprising a wireless radio frequency transmitter connected to receive as input signals the output of said compact disc player, said transmitter controlled to operate within the frequency range of an FM radio, said transmitter power operates below 250 microvolts per meter at three meters in the power range of unintentional power radiators, said transmitter to be used within said automobile and having sufficient power to generate a radio frequency signal which will be detected by the antenna of said automobile, said transmitter transmitting radio frequency signals which are detected by the antenna of the radio of the automobile, said adapter including said transmitter being portable and movable within said automobile without interruption of transmission of said radio frequency signals, said adapter operable to operate within said automobile when it is moving by coupling said radio frequency signal emanating from the transmitter to the antenna of the automobile, said transmitter being tunable by a passenger in the vehicle to a selected transmission frequency such that the FM radio of said automobile is tunable to said selected transmission frequency to enable the compact disc player to play through the antenna input to the FM radio of the automobile.
Claim 3
Dependent Claim
15 words
An adapter as set forth in claim 1, wherein said adapter comprises an integrated circuit.
Claim 4
Dependent Claim
19 words
An adapter as set forth in claim 1, wherein the transmitter operates with a predetermined bandwidth of 200 kilohertz.
Claim 5
Dependent Claim
30 words
An adapter as set forth in claim 3, wherein the transmitter is controlled to operate at a power range which enables effective transmission up to ten feet from the antenna.
Claim 6
Dependent Claim
28 words
An adapter as set forth in claim 1, further comprising a compression circuit located between the output of the compact disc player and the input of the transmitter.
Claim 7
Dependent Claim
20 words
An adapter as set forth in claim 1, wherein the transmitter transmits in stereo to the antenna of an automobile.
Claim 8
Dependent Claim
25 words
An adapter as set forth in claim 6, further comprising manual balance control to control the signal level of the components of the stereo signal.
Claim 9
Dependent Claim
19 words
An adapter as set forth in claim 1, further comprising a pilot tone for signaling the FM stereo receiver.
Claim 10
Dependent Claim
18 words
An adapter as set forth in claim 8, wherein the pilot signal is compatible with standard FM receivers.
Claim 11
Dependent Claim
17 words
An adapter as set forth in claim 9, wherein the pilot signal is set at nineteen kilohertz.
Claim 12
Dependent Claim
21 words
An adapter as set forth in claim 5, wherein said compression circuit comprises a high frequency amplifier to enhance signal-to-noise characteristics.
Claim 13
Dependent Claim
48 words
An adapter as set forth in claim 11, wherein said compression circuit further comprises a clipping circuit connected between said high frequency amplifier and the input of said transmitter to minimize saturation of the input section of said transmitter to limit the peak modulation levels of said transmitter.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-06-06 | 1997-12-06 | 1998-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-06-06 | 2001-12-06 | 2002-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-06-06 | 2005-12-06 | 2006-06-07 | $7700.00 | Window Closed / Lapsed |