System for providing signals from an auxiliary audio source to a

System for providing signals from an auxiliary audio source to a
US 20030060219A1
(19) United States
(12) Patent Application Publication (10) Pub. N0.: US 2003/0060219 A1
Parsiokas
(54)
(43) Pub. Date:
SYSTEM FOR PROVIDING SIGNALS FROM
AN AUXILIARY AUDIO SOURCE TO A
RADIO RECEIVER USING A WIRELESS
(52)
LINK
(57)
Mar. 27, 2003
US. Cl. ....................... .. 455/501; 455/3.02; 455/556
ABSTRACT
(76) Inventor: Stelios Parsiokas, Plantation, FL (US)
Correspondence Address:
An apparatus and method are provided for transmitting
ROYLANCE’ ABRAMS’ BERDO 8‘
audio signals from an auxiliary source such as a satellite
GOODMAN’ L'L'P'
broadcast receiver or a CD or cassette player to a radio
1300 19TH STREET, N.W.
.
SUITE 600
.
.
.
.
receiver located, for example, in a vehicle, using a Wireless
WASHINGTON” DC 20036 (Us)
link. The apparatus comprises a scanning device for locating
open radio frequencies in the RF spectrum of the radio
(21) Appl- NO-I
10/289,255
receiver. The apparatus displays plural RF channel options
_
(22)
Flled:
on a display device and provides a selection device With
NOV‘ 7’ 2002
Which a user selects an RF channel. The apparatus modu
Related US Application Data
lates the audio signals using the selected radio frequency,
and the user tunes the vehicle radio receiver to the selected
(63)
Continuation of application NO- 09/263,201 ?led on
Mar‘ 5’ 1999’ HOW Pat‘ NO‘ 6’493’546'
RF channel. The scanning device continuously scans for
open RF channels and monitors the quality of the RF
Publication Classi?cation
(51)
channel already selected for use as the Wireless link. The
apparatus provides the user With an indication to select
another open channel When the RF channel in use degrades.
Int. Cl.7 ........................... .. H04B 7/015; H04B 1/38
DC SUPPLY
ANTENNA RECEPTOR
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Mar. 27, 2003
US 2003/0060219 A1
SYSTEM FOR PROVIDING SIGNALS FROM AN
AUXILIARY AUDIO SOURCE TO A RADIO
RECEIVER USING A WIRELESS LINK
[0001] This application is a continuation of US. Ser. No.
09/263,207, ?led Mar. 5, 1999.
vehicles Which provides a Wireless link to an existing
vehicle radio receiver. In addition, a need exists for an
RF-coupled satellite broadcast receiver for vehicles Which
automatically selects optimal radio frequencies for Wireless
transmission to the vehicle radio receiver.
SUMMARY OF THE INVENTION
FIELD OF THE INVENTION
The invention relates to a system for providing
[0007] In accordance With one aspect of the present inven
tion, an RF-coupled satellite broadcast receiver is provided
audio signals from an auxiliary source to a radio receiver,
Which scans a radio frequency (RF) band in Which a radio
particularly a vehicle radio receiver, using a Wireless link.
The invention further relates to a method of providing audio
signals to a radio receiver by automatically selecting a
receiver, preferably but not necessarily in a vehicle, can be
[0002]
number of loW noise radio frequencies for Wireless signal
transmission from the auxiliary source to the radio receiver
and providing user controls to select one of the frequencies
for transmission.
tuned for signal reception. The RF-coupled satellite broad
cast receiver selects at least one open RF channel having the
loWest noise ?oor for retransmission of the received satellite
broadcast signal to the radio receiver.
[0008] In accordance With another aspect of the present
invention, the RF-coupled satellite broadcast receiver selects
a plurality of open RF channels having loW noise ?oors and
BACKGROUND OF THE INVENTION
is capable of retransmitting the received satellite broadcast
[0003] A number of systems exist Which use an existing
audio system in a vehicle for playback of audio signals from
signal on any of these available RF channels. The available
RF channel information is provided to the user. The user
selects one of these channels and then tunes the vehicle radio
receiver to the selected channel to listen to the satellite
broadcast program.
a compact disc (CD) player, tape cassette player, satellite
broadcast receiver, or other auxiliary audio source. These
existing systems are designed to play back the signals from
the auxiliary audio source using a number of different
methods. For example, one system receives satellite broad
cast signals and provides them to the optical head of a CD
player, or the magnetic head of a tape cassette player,
BRIEF DESCRIPTION OF DRAWINGS
[0009] The various aspects, advantages and novel features
of the present invention Will be more readily comprehended
already installed in the vehicle. This system is disadvanta
from the folloWing detailed description When read in con
geous because it requires the user to install a removable
junction With the appended draWings, in Which:
adapter to couple the satellite broadcast signal to the optical
or magnetic head of the vehicle audio system.
[0010] FIG. 1 is a block diagram of an auxiliary audio
system constructed in accordance With an embodiment of
[0004] In other systems, signals from an auxiliary audio
the present invention to provide audio signals to an existing
source such as a CD or cassette player are coupled to a
radio via a Wireless link;
vehicle radio receiver via a Wireless link such as an FM
Wireless link. In one system, for example, signals from the
auxiliary audio source are frequency translated to the FM
frequency band and are then broadcast from a transmitter in
the vehicle on several ?xed frequencies for reception by the
vehicle radio receiver. A user then selects one of these
frequencies on the vehicle radio receiver to listen to the
transmitted signals. In another system, a user ?rst selects a
radio frequency in the FM band that is not being utiliZed in
the local area, and then tunes the existing vehicle radio
receiver to the selected frequency. The user then tunes a
transmitter in the vehicle to the same frequency. The trans
mitter receives a signal from a CD player and transmits the
signal at the selected frequency.
[0005] The tWo types of Wireless FM systems described
above are disadvantageous because they do not provide for
automatic monitoring of the radio frequencies used for
retransmitting signals from the auxiliary audio source via the
Wireless link to the existing vehicle radio receiver. The radio
frequencies selected by the user, or the ?xed frequencies
used by the transmitter, may be subject to interference and
poor signal quality. In addition, the manual selection of a
suitable radio transmission frequency is inconvenient to
users.
[0006]
A need therefore exists for an audio coupling
system that overcomes the aforementioned draWbacks of the
existing systems. Speci?cally, a need exists for a radio
frequency or RF-coupled satellite broadcast receiver for
[0011]
FIG. 2 illustrates the installation of the system
depicted in FIG. 1 in a vehicle in accordance With an
embodiment of the present invention;
[0012] FIG. 3 is a block diagram of an interface circuit
constructed in accordance With an embodiment of the
present invention;
[0013]
FIG. 4 is a ?oWchart depicting a sequence of
operations for implementing the system in FIG. 1 in accor
dance With an embodiment of the present invention;
[0014] FIG. 5 is a block diagram of a satellite broadcast
receiver for use With the system depicted in FIG. 1 in
accordance With an embodiment of the present invention;
[0015] FIG. 6. is a block diagram of a level control and
de-emphasis circuit for use With the system depicted in FIG.
1 in accordance With an embodiment of the present inven
tion;
[0016] FIG. 7 illustrates a scanning receiver constructed
in accordance With an embodiment of the present invention;
and
[0017] FIG. 8 illustrates an auxiliary audio signal pro
cessing and display device constructed in accordance With
an embodiment of the present invention.
[0018] Throughout the draWing ?gures, like reference
numerals Will be understood to refer to like parts and
components.
Mar. 27, 2003
US 2003/0060219 A1
DETAILED DESCRIPTION OF THE
PREFERRED EMBODIMENTS
[0019] A system 10 for providing satellite broadcast sig
nals 13 or audio signals from another auxiliary audio source
to an existing radio receiver 24 (e.g., in a vehicle) using a
Wireless link 15 in accordance With the present invention is
depicted in FIG. 1. The system 10 comprises an antenna 12
such as a satellite S-band antenna (operable at about 2.3
GigahertZ) for receiving satellite broadcast signals. The
antenna 12 is connected via a coaxial cable 14, for example,
to an auxiliary audio signal processing and display device
16, Which is hereinafter referred to as the interface device
16. Another antenna 18 is connected to the interface device
16 to transmit signals therefrom to a radio receiver 24
comprising a tuner 20 and an antenna 22.
[0020]
The antenna 12 and its associated circuitry (e.g., a
loW noise ampli?er) can be connected internally or exter
nally With respect to a vehicle. The antenna 12 can be used
to receive satellite digital audio radio service (SDARS), a
satellite broadcast service recently established by the US.
Federal Communications Commission (FCC), in a vehicle.
As shoWn in FIG. 2, the antenna 12 can be mounted on the
roof 17 or rear WindoW 19 of a vehicle 23, for example. The
cable 14 connects the antenna 12 to a remote unit 11 forming
a part of the interface unit 16 of FIG. 1. The remote unit 11
can comprise, for example, an SDARS receiver. The remote
unit 11 can be placed in the cab 25 of a car or truck, for
example. To avoid having to drill a hole in the truck or car
23 to install the cable 14, a device 21 can be mounted on the
exterior of the vehicle’s rear WindoW 19 using an adhesive
converter) or from batteries. Thus, the interface device 16
can be used inside a home, for example, or in conjunction
With a portable radio.
[0022] With continued reference to FIG. 1, the radio
receiver 24 is preferably a conventional amplitude modula
tion
and frequency modulation (FM) radio provided as
standard equipment in many vehicles. The antenna 22 is
con?gured to receive AM and/or FM signals. In accordance
With the present invention, the radio receiver 24 need not be
modi?ed in any Way to output the audio programming
provided by the satellite broadcast signals or by another
auxiliary audio source. The antenna 18 is preferably an FM
antenna, and the interface 16 device is operable to convert
the satellite broadcast signals received via the antenna 12 to
FM-band signals for retransmission from the antenna 18 to
the radio receiver 24. Thus, the system 10 of the present
invention operates With existing radios. It is to be under
stood, hoWever, that the present invention can be con?gured
to operate With other types of receivers using Wireless links
at radio frequencies other than the AM and FM bands.
[0023]
The interface device 16 preferably comprises a
display 36 for indicating one or more radio frequencies that
are selected by the interface device for providing the Wire
less link 15. In the example illustrated in FIGS. 1 and 8, the
interface device 16 has determined that the radio frequencies
of 88.5 MegahertZ (MHZ), 98.7 MHZ and 103.5 MHZ are
relatively loW noise, open channels Which can be used for
the Wireless link 15. The user can select one of these
channels (e.g., 88.5 MHZ) for transmission by the interface
device 16 by selecting one of the corresponding buttons 30,
circuitry. The device 21 can be capacitvely coupled With
32 and 34 provided on the interface device 16. The buttons
30, 32 and 34 can be implemented as touch screen buttons,
for example. The user then selects the same frequency (88.5
MHZ in the present example) on the vehicle tuner 20 using
another device 29 Which is connected to the cable 14. The
other device 29 can be mounted on the inside of the WindoW
provided on the radio receiver 24 for selecting a radio
19 opposite the ?rst device 21 using the same adhesive
station. The selected radio channel (e.g., 88.5 MHZ) is
material. The remote unit 11 is connected to a display and
indicated on the tuner display 46 in a conventional manner.
The tuner 20 can also be a chassis With a tuner and a tape
material Which supports the antenna 12 and associated
control unit 27, also forming a part of the interface device 16
of FIGS. 1 and 8, via a Wireline 31 or Wireless link to the
dashboard or other location in vieW of the driver. The display
and control unit 27 can comprise the scanning receiver, the
RF modulation and transmission devices and the display and
control devices. In accordance With an embodiment of the
present invention, the channels of the SDARS receiver can
be changed remotely using the display and control unit 27.
Alternatively, the interface device 16 can be installed as a
single unit on or near the dashboard and therefore accessible
a tuning dial 42 or one of a number of preset buttons 35
cassette player as indicated by the cassette slot 40. A CD
player can be provided in lieu of, or in addition to, the
cassette player. A volume control dial 44 is provided in a
conventional manner.
[0024] The interface device 16 Will noW be described in
more detail With reference to FIG. 3. As shoWn in FIG. 3,
the interface device 16 includes an auxiliary audio source
such as an S-band satellite receiver 50. The satellite receiver
to the driver of the vehicle 23. As described beloW and
50 can also be operated in other RF bands and have, for
illustrated in FIGS. 1 and 8, the interface device 16 (or, in
the tWo-part installation shoWn in FIG. 2, the display and
control unit 27) comprises a display 36 for indicating one or
example, an L-band or UHF front-end for use With direct
more RF channels to Which the user can tune the radio
receiver 24 to complete the Wireless link 15. The display and
control unit 27 can also be provided With channel selection
buttons 38, Which are described beloW.
[0021] As shoWn in FIG. 1, the system 10 of the present
invention comprises a DC poWer supply adapter 26 Which
can be inserted in the cigarette lighter socket 28 provided in
the dashboard of most vehicles to provide poWer to the
system 10. The interface unit 16 can also be con?gured as a
portable device Which can be disconnected from the vehicle
and operated from an AC outlet (using a suitable AC/DC
audio broadcast (DAB) systems in different countries. The
auxiliary audio source can also be a CD or cassette player 52
or other device, and can be located external to the interface
device 16 via an external source input if desired. The
satellite receiver 50, described beloW in connection With
FIG. 5, preferably doWnconverts and processes the received
satellite broadcast signal to obtain a baseband signal. Alter
natively, the satellite receiver 50 can doWnconvert the sat
ellite broadcast signal to an intermediate frequency
The
output signal from the satellite receiver is processed via a
level control and pre-emphasis circuit 54, Which is described
beloW in connection With FIG. 6. The level control and
pre-emphasis circuit 54 provides a composite stereo signal
to an RF modulator 56.
US 2003/0060219 A1
[0025]
In accordance With the present invention, the RF
modulator 56 converts the composite signal to a radio
frequency selected using a scanning receiver 58. The scan
ning receiver 58 preferably continuously monitors the RF
Mar. 27, 2003
sending a signal to the scanning receiver 58 to initiate the
scanning algorithm for the scanning device 73. The scanning
device 73 is preferably programmed to scan every 200 kHZ
for operation in conjunction With an FM broadcast trans
mission system in the United States. The scanning device 73
can be programmed to operate in accordance With different
spectrum of the geographic area in Which the vehicle is
located via an antenna 61 for open RF channels (i.e., RF
channels that have no transmitted broadcast signals). The
scanning receiver 58 also determines Which of the open
bands in other countries so as to scan every 100 kHZ of the
frequencies satisfy predetermined criteria for loW noise
FM broadcast band in Europe, for eXample. The scanning
(e.g., comparatively small signal strength). In other Words,
device 73 is connected to a received signal strength detector
the scanning receiver 58 locates RF channels having a
74 Which provides a received signal strength indicator
(RSSI) to the microcontroller 60. The microcontroller 60
signal-to-noise ratio (SNR) beloW a pre-determined level
(e.g., beloW about 5 decibels). These RF channels are
generally not used by broadcast stations in a particular
geographic area and do not exhibit the hissing or muting
often associated With a Weak broadcast signal that is unac
ceptable to a listener. When an RF channel is located Which
channel spacing allocations and radio frequency broadcast
determines if any of the scanned frequencies meet the
pre-de?ned criteria for the Wireless link is described previ
ously. Weak channels are detected as loW voltage signals,
Whereas strong signals are detected at higher voltage signals.
The microcontroller 60 preferably selects the three loWest
meets these criteria, the scanning receiver 58 provides the
energy or Weak channels having the loWest voltages mea
radio frequency to a microcontroller 60. The microcontroller
sured by the detector 74. Selected scanned frequencies
60 is programmed to display at least one, and preferably
several, radio frequencies on the display 36 Which represent
possible loW noise, open channels for the Wireless link 15.
Which meet the pre-de?ned criteria are indicated on the
The microprocessor 60 is also programmed to provide a user
With a user interface 66 With Which to select one of the
possible open channels (e.g., buttons 30, 32 and 34). For
eXample, the microcontroller 60 can implement the three
buttons 30, 32 and 34 as a touch screen interface in con
junction With the display 36 for selecting any of three open
channels (i.e., 88.5 MHZ, 98.7 MHZ or 103.5 MHZ in the
eXample shoWn in FIG. 1). Other aspects of the display 36
Which represent advantages of a satellite receiver are
described beloW With reference to FIG. 8.
[0026]
After the user selects one of the channel options
display, as shoWn in FIGS. 1 and 8, by the microcontroller
60.
[0029] As shoWn in FIG. 8, the display 36 can provide
additional information other than the radio frequencies of
channels from Which a user can select for implementing the
Wireless link 15. The microcontroller can receive data 43
from the satellite receiver relating to SDARS services via an
input line 75, as shoWn in FIG. 3. The SDARS services data
43 can include, for example, satellite broadcast channel
number 45, artist name, audio program title and data channel
information. The interface device 16 also comprises the
poWer button 41, the scan button 70, the satellite broadcast
channel selection buttons 38, as Well as volume control and
tuning buttons 37 and 39. The microcontroller 60 can
provided by the scanning receiver 58 for the Wireless link
15, the microcontroller 60 provides an output signal to the
indicate via the display 36 the random channel selection of
RF modulator to modulate the baseband or IF signal from
the scanning receiver 58, the signal strength (i.e., RSSI) of
the level control and pre-emphasis circuit 54 using fre
quency miXing. Accordingly, the audio signal from the
effects (e.g., a dynamic bar graph display corresponding to
auXiliary audio source 50 or 52 is modulated onto the
selected RF channel for transmission via the Wireless link
15, folloWing ampli?cation by an RF poWer ampli?er 64.
[0027] The starting point of the scanning receiver 58, that
is, the ?rst RF channel of the algorithm controlling the
scanning receiver 58, is selected automatically and ran
domly to avoid all receivers selecting the same unused
channels in a particular geographic area and to minimiZe
vehicle-to-vehicle interference. It is to be understood that the
RF channel need not be in the FM radio broadcast spectrum.
For eXample, the Wireless link 15 can be implemented in the
AM radio broadcast spectrum. In that case, the scanning
receiver 58 and the RF modulator are operated using AM
radio broadcast frequencies. The scanning receiver 58 pref
erably commences scanning upon poWer-up of the interface
device 16. The interface unit 16 also comprises a scan button
70, as shoWn in FIGS. 1 and 8, Which alloWs a user to
manually initiate scanning via the scanning receiver 58.
[0028] An eXemplary scanning receiver 58 is depicted in
satellite or terrestrially repeated SDARS signals, and visual
the output levels of the audio program from the auXiliary
audio source), among other displayable information. The
display 36 can also indicate the user’s current frequency
selection 33 for the Wireless link 15. In addition, selected
open channels in metropolitan areas such as NeW York City
or Los Angeles can be preset on the interface device 16 and
selected via a button 47, for eXample.
[0030] The selection of an RF channel for the Wireless link
15 Will noW be described With reference to the How chart
depicted in FIG. 4. As stated previously, the scanning
receiver 58 commences scanning an RF spectrum (e.g., the
FM radio broadcast band) upon poWer-up or after the user
activates the scan button 70 on the interface device 16 (block
78). The scanning receiver 58 preferably determines a
number of RF channels (e.g., betWeen one and three RF
channels) to be open and to have suf?ciently loW noise for
use as the Wireless link 15 (block 80). If no RF channels can
be located, the scanning receiver 58 continues to scan, as
indicated by the positive branch of decision block 82. The
scanning receiver 58 preferably continuously scans even if
FIG. 7. The scanning receiver 58 comprises an ampli?er 72
to amplify the signals received via the antenna 61. A
scanning device 73 can be provided With an input to receive
suitable RF channels are reported to the microcontroller 60
since conditions may change over time. In accordance With
signals from the microcontroller 60. When the scan button
receiver 58 can interrupt scanning if a number of RF
70 is activated by a user or the interface device 16 is turned
channels are located Which are suitable for the Wireless link
on (i.e., via button 41), the microcontroller 60 responds by
15. The scanning receiver 58 can then resume scanning after
another embodiment of the present invention, the scanning
Mar. 27, 2003
US 2003/0060219 Al
the scan button 70 is activated or sound quality on the RF
channel selected by the user for the Wireless link 15
decreases below a predetermined threshold. In the mean
time, only the transmitting antenna 18 is operating, and the
time diversity are useful When a mobile satellite receiver is
traveling in a suburban or rural area Where line of sight
blockage With respect to the antenna 12 and the satellite
occurs due to bridges, trees and loW buildings. On the other
receiving antenna 61 is not functional. In this case, the
hand, terrestrial retransmission of satellite signals is useful
antenna 18 can serve as both a transmitting and receiving
in areas Where tall buildings are located, such as central city
and metropolitan areas.
antenna With a splitter connection to the RF poWer ampli?er
64 and the scanning receiver 58, respectively, and the
antenna 61 can be eliminated. In other Words, the antenna 18
is connected to the scanning receiver 58 during the scanning
mode and is disconnected from the RF ampli?er 64. When
a number of RF channels have been located for the Wireless
link 15, the antenna 18 is used for transmitting on a selected
one of the RF channels and scanning through the antenna 18
is interrupted.
[0031]
With continued reference to FIG. 4, the microcon
troller 60 displays the channels selected by the scanning
receiver 58 on the display 36 (block 84). The user selects one
of the channels indicated on the display 36 and then tunes
the radio receiver 24 to that channel (block 86). The user
then commences monitoring the sound quality of the Wire
less link 15 (block 88). As stated previously, the scanning
receiver 58 preferably continuously scans. When the
selected RF channel is determined by the scanning receiver
to be above a predetermined noise threshold, the scanning
receiver 58 provides a signal to the microcontroller 60 to
indicate to the user via the display 36 and/or a sound
generating device that sound quality is poor (blocks 90 and
92). The user can then select another RF channel indicated
on the display device 36.
[0034] In FM broadcasting, high audio frequencies are
emphasiZed to improve the signal-to-noise ratio (SNR).
Thus, a conventional FM tuner such as the tuner 20 is
provided With a de-emphasis circuit for obtaining a ?at
frequency characteristic. Accordingly, the level of the output
signals from the satellite receiver 50 or the CD/cassette
player 52 of FIG. 2 are adjusted by the circuit 54 (shoWn in
detail in FIG. 6) to prevent the attenuation of high audio
frequencies by the de-emphasis circuit in the tuner 20. Such
processing is described in US. Pat. No. 5,448,757, issued to
Hirata on Sep. 5, 1995, incorporated herein by reference.
With reference to FIG. 6, the left and right channels in the
audio signals recovered by the satellite receiver are pro
cessed by a stereo modulator 116 and an automatic level
control (ALC) circuit 118 connected to the output of the
pre-emphasis circuit 114. The stereo modulator 116 modu
lates the audio signals from the satellite receiver 50 to a
composite signal. The ALC circuit 118 controls the input to
the stereo modulator 116 to reduce distortion.
[0035] Although the present invention has been described
With reference to a preferred embodiment thereof, it Will be
understood that the invention is not limited to the details
thereof. Various modi?cations and substitutions have been
[0032] An exemplary satellite receiver 30 is depicted in
suggested in the foregoing description, and others Will occur
FIG. 5. The S-band signals received by the antenna 12 of
FIGS. 1-3 are ampli?ed by ampli?er 96 prior to doWncon
to those of ordinary skill in the art. All such substitutions are
intended to be embraced Within the scope of the invention as
version to an IF via a mixer 98 and a local oscillator (LO)
de?ned in the appended claims.
100. The recovered IF signal is then processed via an IF ?lter
and ampli?er 102 prior to obtaining the digital baseband
information transmitted via satellite. For example, the recov
ered IF signal can be converted to a digital representation
thereof using an analog-to-digital converter (ADC) 104 prior
to phase shift keying (PSK) demodulation by a demodulator
106 if the baseband signal is PSK-modulated at the broad
cast station. The satellite broadcast signals can be time
division multiplexed (TDM) signals and may therefore
comprise information from a number of broadcast programs,
as Well as having TDM data representing the left and right
stereo channels corresponding to the same broadcast pro
gram. Accordingly, a TDM demultiplexer 108 is provided in
the satellite receiver 50 to recover the information from the
TDM broadcast channels. The recovered information corre
sponds to the satellite broadcast program selected by the
user via the user interface 66, for example, as indicated at
107. The recovered information can be processed at the
broadcast stations to provide forWard error correction (FEC)
coding, Which is decoded using an FEC 110 decoder at the
receiver 50. Finally, the recovered baseband data can be
converted into analog audio signals using an audio decoder
112 such as an MPEG decoder.
[0033] In accordance With an aspect of the present inven
tion, the interface device 16 can be implemented to convert
the radio receiver 24 into a dual-mode receiver in a satellite
broadcast system in Which measures such as time and space
diversity and terrestrial retransmission have been taken to
improve satellite signal reception at the vehicle. Space and
What is claimed is:
1. Asystem for providing audio signals to a radio receiver
from an auxiliary audio source comprising:
an input for receiving said audio signals from said aux
iliary audio source;
a processing device connected to said input and operable
to substantially continuously monitor a selected radio
frequency spectrum to identify radio frequency chan
nels that satisfy a predetermined open channel criteria,
and to automatically select at least one radio frequency
satisfying said predetermined open channel criteria at
Which to transmit said audio signals to said radio
receiver via a Wireless link, and to modulate said audio
signals on said selected radio frequency; and
an antenna connected to said processing device and
operable to transmit said audio signals to said radio
receiver using said at least one radio frequency;
Wherein said processing device further comprises an
output device for indicating said at least one radio
frequency to a user to alloW said user to tune said radio
receiver to said at least one radio frequency.
2. A system as claimed in claim 1, Wherein said at least
one radio frequency is selected from one of an amplitude
modulation radio broadcast spectrum and a frequency modu
lation radio broadcast spectrum.
3. Asystem as claimed in claim 1, Wherein said processing
device is operable to monitor the quality of said at least one
Mar. 27, 2003
US 2003/0060219 A1
radio frequency, to select another radio frequency When said
at least one radio frequency degrades, and to generate a
second indication signal to instruct said user to tune said
radio receiver to said another radio frequency.
4. Asystern as claimed in claim 1, Wherein said processing
device is operable to randomly select a ?rst radio frequency
Which satis?es said predetermined open channel criteria
from said selected radio frequency spectrum in response to
poWering up of said processing device.
5. Asystern as claimed in claim 1, Wherein said processing
device comprises a scanning receiver for automatically
scanning said predetermined radio frequency spectrum and
selecting a radio frequency therein for said Wireless link.
6. Asystern as claimed in claim 1, Wherein said processing
indicating said at least one radio frequency to a user to
alloW said user to tune said radio receiver to said at
least one radio frequency.
11. Arnethod as claimed in claim 10, Wherein said step of
autornatically selecting said at least one radio frequency
comprises the step of randomly selecting a ?rst radio fre
quency Which satis?es said predetermined open channel
criteria from said selected radio frequency spectrum in
response to poWering up of said processing device.
12. A method as claimed in claim 10, further comprising
the steps of:
monitoring the quality of said at least one radio fre
quency;
device is operable to automatically and dynamically identify
a plurality of radio frequencies satisfying said predetermined
selecting another radio frequency When said at least one
open channel criteria at Which to transmit said audio signals
to said radio receiver.
7. Asystern as claimed in claim 6, Wherein said processing
instruct said user to tune said radio receiver to said
radio frequency degrades; and generating a signal to
another radio frequency.
device further comprises a display device for displaying said
13. A method as claimed in claim 10, further comprising
the steps of:
plurality of radio frequencies and a selection device to alloW
scanning said predetermined radio frequency spectrum;
a user to select one of said plurality of radio frequencies.
8. Asystern as claimed in claim 7, Wherein said processing
device rnodulates said audio signals using said selected one
of said plurality of radio frequencies in response to said
selection device.
9. Asystern as claimed in claim 7, Wherein said processing
device is operable to monitor the quality of said at least one
radio frequency selected via said processing device, and to
generate a signal to instruct said user to tune to another said
plurality of radio frequencies When said at least one radio
frequency degrades, said user selecting said another one of
said plurality of radio frequencies via said selection device.
10. A method of providing a audio signals to a radio
receiver from an auXiliary audio source comprising the steps
of:
receiving said audio signals from said auXiliary audio
source;
and
selecting a radio frequency therein for said Wireless link.
14. A method as claimed in claim 13, Wherein said
predetermined radio frequency spectrum is one of an ampli
tude rnodulation radio broadcast spectrum and a frequency
modulation radio broadcast spectrum.
15. A method as claimed in claim 10, further comprising
the steps of automatically and dynamically identifying a
plurality of radio frequencies at Which to transmit said audio
signals to said radio receiver.
16. A method as claimed in claim 15, further comprising
the steps of:
displaying said device to alloW a user to select one of said
plurality of radio frequencies. plurality of radio fre
quencies; and
providing a selection
17. A method as claimed in claim 16, further comprising
substantially continuously monitor a selected radio fre
quency spectrum to identify radio frequency channels
that satisfy a predetermined open channel criteria;
one of said plurality of radio frequencies in response to said
autornatically selecting at least one radio frequency sat
isfying said predetermined open channel criteria at
Which to transmit said audio signals to said radio
18. A method as claimed in claim 16, further comprising
the steps of:
monitoring the quality of said at least one radio frequency
receiver via a Wireless link;
rnodulating said audio signals to said selected radio
frequency;
transmitting said audio signals to said radio receiver using
said at least one radio frequency; and
the step of rnodulating said audio signals using said selected
input device.
to determine When said at least one radio frequency
degrades; and
generating a signal to instruct said user to tune said radio
receiver to one of said plurality of radio frequencies.
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