Telecommunications – Transmitter and receiver at separate stations – With control signal
Patent
1996-02-23
1998-12-29
Le, Thanh Cong
Telecommunications
Transmitter and receiver at separate stations
With control signal
455345, H04B 106
Patent
active
058549692
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention concerns an apparatus for providing sound in vehicles, comprising a receiver for radio-frequency waves with frequency selection, an antenna connected to said receiver, an operating means located in the vehicle close to the driver's seat including a power amplifier with controls for adjusting the sound volume, and loudspeakers connected to said power amplifier.
BACKGROUND OF THE INVENTION
Equipment for receiving radio waves and producing sound in vehicles generally comprise a stereo radio-cassette. The available space is very limited for the controls needed for programming the transmitter frequencies, adjusting the sound or operating the tape player. This implies that the control buttons can rarely be of an advantageously ergonomic design. The stereo radio-cassette is often completed with a CD-switcher placed in the luggage compartment of the vehicle, which requires an extra operating unit on the operating panel for controlling the CD-switcher.
The radio antenna generally has to be placed at such a long distance from the radio unit that a separate antenna amplifier is needed. It is even known to place the whole radio unit near to an antenna in the rear part of the car, e.g. as in U.S. Pat. No. 4910796, and to transmit the LF-signal to a power amplifier at the operating part in the operating panel. This then necessitates several conductors to transmit stereo signals, and also a conductor to transmit the station selection signal.
Vehicle manufacturers are also faced with a problem to integrate ever more technically complicated sound systems in the environment of the driver. Owing to the RDS-technique, the car radio is used to an ever greater extent for receiving traffic messages. A substantial problem for vehicle suppliers is that different markets, like western Europe, USA, Australia, Japan and eastern Europe, make use of different frequency bands for radio reception, and development goes a way where new digital transmission techniques also end up on different frequency bands. The costs to supply different markets with different system variants get very high. Furthermore, the costs to install these systems in a vehicle are high.
TECHNICAL PROBLEM
The purpose of the present invention is therefore to attain an apparatus for providing sound in vehicles, which simplifies the adaptation to different markets by reducing both the costs for the hardware required to offer different system variants and the installation need after the vehicle has left the assembling factory as well.
SOLUTION
For this purpose, the invention is characterized in, that said radio receiving means is divided into a master unit close to the driver's seat in the vehicle, and a slave unit which is located together with the antenna remotely from said master unit, said slave unit comprises a circuit controlled from said master unit for selecting a desired transmitter frequency and a circuit for converting the selected signal into a signal of intermediate frequency with mainly a constant frequency, and said master unit comprises a detector, a pre-amplifier and said power amplifier along with controls for adjusting the receiver.
DESCRIPTION OF THE DRAWINGS
The invention will be described herebelow with reference to the preferred embodiment which is shown on the accompanying drawings wherein
FIG. 1 schematically shows a vehicle with the apparatus of the invention in a perspective view, and
FIG. 2 is a block diagram which schematically shows a sound equipment for a vehicle designed according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The vehicle 10 shown in FIG. 1 is equipped with a window pane antenna 11 mounted on the left rear window pane. The antenna is connected to a slave unit 12 placed relatively close to the same. This slave unit forms a radio receiving means which is in turn connected through a coaxial cable 13 to a master unit 14 placed in the vehicle close to the driver's seat with an operating panel that preferably comprises a power amplifier, a tape player and controls
REFERENCES:
patent: 4521232 (1985-06-01), Sakurai
patent: 4907291 (1990-03-01), Yamamoto
patent: 4910796 (1990-03-01), Nakase et al.
patent: 5276918 (1994-01-01), Cornforth et al.
AB Volvo
Cong Le Thanh
LandOfFree
Stereo apparatus that includes a master unit and a slave unit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Stereo apparatus that includes a master unit and a slave unit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stereo apparatus that includes a master unit and a slave unit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1430468