REAR CHANNEL HOME THEATER WIRELESS SPEAKER SYSTEM
This invention relates to an improved system for transmitting audio signals
to a rear channel speaker used in home theater systems.
The advent of home theater systems has been greeted with great
acceptance by the consumer public. In this regard, home theater systems include
the use of speakers arranged around a room to provide the home theater
experience. In particular, and as one aspect of the home theater experience, there
is a need for rear speaker sound. As may be understood, rear speaker sound is
achievable, but hard wiring is conventionally used. Hard wiring is unattractive,
generally undesirable to many people and should, preferably, be avoided if
possible.
The assignee of this invention, Recoton Corporation, owns a number of
patents relating to 900 MHz technology. The 900 MHz technology generally
relates to RF 900 MHz signals allowing for a transmitter and remote wireless
receivers to be separated by up to 1 50 feet. Sometimes, at 900 MHz
transmission frequencies, interference can occur due to use of other appliances
such as telephones and the like which may receive or transmit at substantially
similar or close frequencies. As a consequence, it is desirable to provide wireless
rear channel speakers without utilizing RF transmission in the 900MHz range.
An object of this invention is to provide a rear channel wireless speaker
system employing a transmission system in which there is little if any chance of
interference.
Another object of this invention is to provide such a rear channel wireless
speaker system which is easy to assembly, inexpensive and very reliable.
Yet another object of this invention is to provide such a rear channel
speaker system in which the power for the rear channel speaker can be self
contained, either being rechargeable batteries, conventional batteries or a plug-in
AC/DC converter.
Yet another object of this invention is to provide such a rear channel
wireless system which will be easy to mount, attractive in appearance and
susceptible to easy use.
Other objects, advantages and features of this invention will become more
apparent from the following description.
SUMMARY OF THE INVENTION
In accordance with the principles of this invention, the above objects are
accomplished by providing a magnetic induction local area wireless transmission
system in which magnetic induction is provided to transmit the audio signal from
a television to the rear channel speaker. Magnetic induction system has iimited
ranges for transmitting audio signals, but magnetic induction systems can be
designed to operate within FCC regulations and provide reasonably effective
transmission for distances up to 25 feet. Such a range is acceptable and utilizable
for rear channel home theater speaker systems because the distance between the
television and receiver for the rear channel is rarely greater than 25 feet, and in
most cases, is less than 1 5 feet.
In order to prolong the life of battery power utilized with the present
invention, when there is no signal present being transmitted, the receiver's power
is turned off. So long as there is no signal present, the power will not be turned
on, but the receiver may be provided with a signal to determine whether or not
there is a transmitted signal. When there is a transmitted signal, it will
automatically reactivate the battery circuitry to cause the receiver circuit to be
able to receive transmitted information.
The present invention intends to utilize a chip set provided by a company
identified as AURA Corp. Additionally, U.S. Patent 5,771 ,438 issued June 23,
1 998 to Palermo et al describes a conventional magnetic system with transmitter
electronics and receivers shown therein. Insofar as conventional magnetic
transmitter electronics and receivers are employed, the '438 patent is illustrative
of a prior art system which can be employed in the present invention.
DESCRIPTION OF THE DRAWING
Fig. 1 is a block diagram is a block diagram of the present invention
employed in a home theater system in which the magnetic transmission system
is used for rear channel speakers.
DETAILED DESCRIPTION
A television 1 0 having its normal complement of adjacent speakers 1 2
and 1 4 is located at the front of a room 1 6. The audio output emanating from
the television is connected to a magnetic transmitter 1 8 substantially as
described in U.S. Patent 5,771 ,438. The listener is located in front of the
television as at a couch or a chair 20, and a pair of rear channel speakers are
located behind or at the rear sides of the room as at 22 and 24. Each of the
rear speakers is connected to a shelf-like assembly easily mounted on the wall,
with the shelf-like assembly including therein the wireless magnetic receiver 26,
28. The details of the wireless magnetic receiver are identified in U.S. Patent
5,771 ,438
An alternative embodiment includes a single receiver 30 connected to a
pair of speakers 32.
The transmitter includes a view meter identifying the level of power
emanating therefrom. The rear receivers operate with battery power wherein
the battery is either rechargeable or not, or the DC power can be provided by an
AC/DC converter connected into a standard outlet. Preferably, the speakers are
powered solely by batteries which enable the rear channel speakers to be easily
mounted to a wall anywhere in the rear of the room without the need for power
outlets.
As a feature of the present invention, the receivers automatically turn or
off depending upon the presence of a transmitted signal. Further, the
transmitter receiver system includes full diversity and channelization with up to
eight channels.
The present invention provides a highly efficient magnetic coupling circuit
for rear channel home theater utilization in which the audio signal emanating
from the TV is transmitted through the magnetic transmission system to the rear
channel speaker employing the magnetic receiver so as to produce audio within
the home theater environment. By providing portable battery power, the
speakers may be piaced in any desired location so as to emphasize and maximize
the effect of the home theater effect. Further, by employing magnetic induction,
interference which might be present if RF wireless transmission is eliminated,
and the magnetic transmission is highly stable thereby providing excellent and
reliable rear channel sound.
While this invention has been described with respect to particular
applications, it will be appreciated that the described home theater system
may be used for other purposes. Many other variations and applications of
the invention will be apparent. The above specification and the detailed
description of the preferred embodiment are to be considered as representative
only, as the scope of the invention is intended to be covered by the scope of the
claims, as interpreted by the courts, and their reasonable and legal equivalents,
as also interpreted by the Courts and the applicable statutes.