CA2033835A1 - Wireless stereo audio/video signal transmitter and receiver system apparatus with remote control extender capability - Google Patents

Abstract

S P E C I F I C A T I O N

WIRELESS STEREO AUDIO/VIDEO SIGNAL TRANSMITTER
AND RECEIVER SYSTEM APPARATUS
WITH REMOTE CONTROL EXTENDER CAPABILITY

ABSTRACT OF THE INVENTION

A wireless stereo audio/video signal transmitter and receiver system apparatus with remote control extender capability capable of accepting external baseband stereo audio and video signal inputs. A transmitter FM modulates a stereo audio/video signal which is transmitted on an RF carrier to one or more remote receivers which regenerate the original stereo audio/video signal providing both baseband stereo audio and video signal outputs as well as a mono audio/video signal output modulated at a particular television channel. A handheld RF remote control transmitter serves to permit the remote operation of the source of the external stereo audio/video signal by transmitting an RF
remote control signal to a remote control receiver contained within the transmitter housing which receives the RF remote control signal and regenerates a corresponding IR remote control signal to actuate the various functions of the stereo audio/video signal source device.

Description

21~33835 BACKGROUND OF ~ INVENTION
The present invention relates generally to the transmission of audio/video television and remote control signals from a local location to a remote location, and, in particular, to a wireless audio and video transmitter and receiver system apparatus capable of accepting external baseband stereo audio and video signal inputs. In the present wireless stereo audio/video signal transmitter and receiver system apparatus the transmitter transmits an FN modulated audio/video signal via an RF carrier in the 900 MHz band to a remote receiver which regenerates the original audio/video signal providing both baseband stereo audio and video signal outputs as well as a modulated mono audio/video signal output corresponding to a particular television channel.
In addition, a handheld RF remote control transmitter provided at the remote location transmits RF remote control signals to a remote control receiver which receives the RF remote control signal and regenerates a corresponding IR remote control signal to actuate the local stereo audio/video signal source device.
Advances in technology and manufacturing have resulted in the video cassette recorder (VCR~ becoming virtually common place in households which own a television set with such VCR's almost always possessing stereo audio and remote control capability. In homes owning multiple television sets, the VCR is typically placed adjacent to and hardwire connected to a single designated television set. Should the user desire to view a video cassette, the user has to view the video cassette on the particular television set to which the VCR is physically attached. Sbould the user wish to view the video cassette on another television set, one alternative is to disconnect the VCR
i from its designated television set, transport the VCR to the ;~ remote location and reconnect the VCR at the remote television.
Another alternative consists of hardwire connecting multiple television sets to a single VCR using multiple selector switches to "make" the desired connections to cause the VCR's audio/video ~3~8~

signal to be directed to the desired television set. Stereo VCR's may further require additional wiring to accommodate the stereo audio signal capabilities of such VCRs. Likewise, if one desires to view a television program which is supplied to the homeowner via a cable television network, the television which the homeowner wishes to view must be connected to the cable television network.
In theft prevention and other security applications, where video cameras are utilized, video cameras must each be physically hardwired to a monitoring station, or recording device, often located at distances remote from the camera's location. In such situations, great lengths of connecting wire may be required, connections which are susceptible to damage over time and/or cutting by one attempting to defeat a security camera.
The limitations of such physical connections are apparent in that one must either physically move the VCR about the house or endure the expense and/or unsightliness of having wire~ run from television to television as well as the ongoing risk of damage to any such connecting cables.
In addition, where a audio,'video signal source such as a VCR is connected to drive a remotely placed television the standard remote control device typically supplied by the VCR
manufacturer is usually inoperative from the remote location inasmuch as such standard VCR remote control devices most often utilize infra-red (IR) light signals to communicate remote instructions to the VCR. The standard remote control's use o~ IR
signals requires that the standard remote control be held by the user in a "line-of-sight" with the VCR in order to operate since infra-red signals will not penetrate walls, door~, floors or other solid objects and instead usually will reflect off of or be absorbed by such objects. Where walls, doors and floors separate the VCR from the remote television, as is usually the case in most home situations, the supplied IR remote control will not function to control the VCR from the remote location , : , , .: ~ , . - : . ~ . .

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necessitating that the user walk from the remote television to the VCR to perform even the simplest function such as pausing a video cassette tape being played.
Accordingly the present invention seeks to address these limitations by providing for the wireless transmission and reception of television signals on an RF band of 90~ MHz by taking advantage of FCC regulations which allocates a portion of the 900 MHz band for this application. In addition, the present invention seeks to address the inoperability of typical standard infra-red based remote control devices by providing for the wireless transmission and reception of remote control signals on an RF band on the order of 500 MHz and regeneration of IR remote control signals at the location adjaoent the audio/video signal source device to be controlled.
Moreover, the present invention seeks to provide for a flexible wireless transmission and reception of television signals in a manner which provides for the best possible television picture at the remote television set using the least costly combination of components.
Accordingly, it is an object of the present invention to provide a wireless stereo audio/video signal transmitter and receiver system apparatus having remote control extender capability which is capable of accepting baseband stereo audio and baseband video signals as inputs to a transmitter.
Another object of the present invention is to provide a wireless stereo audio/video signal transmitter and receiver system apparatus having remote control extender capability which is capable of accepting a baseband stereo audio input and transmitting to a remote receiver.
~It is yet a further object of the present invention to -provide a transmitter which separately processes the two audio channels forming the stereo audio signal, combines the stereo audio and video signals and modulate the signals onto an RF
carrier.

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~ `` 2033835 It is an object of the present invention to utilize FM
modulation in order to transmit a signal which does not possess the limitations of AM modulated signals.
It is still a further object of the present invention to provide a receiver which down converts a received RF signal to an IF frequency.
It is yet another object of the present invention to provide a handheld RF remote control transmitter capable of transmitting an encoded RF remote control signal corresponding to the remote control key code function generated by the standard IR
remote control device and thus able to penetrate walls, doors, floors and other physical obstructions.
Another object of the present invention is to provide a remote control receiver incorporated into the transmitter housing which receives the RF remote control signal and regenerates the appropriate IR remote control signal directing same toward the audio/video signal source device toward actuating same.
Yet another object of the present invention is to provide a remote control receiver which may be programmed by the standard IR remote control device and handheld RF remote control transmitter to recogni~e received RF remote control signals and transmit corresponding IR remote control signals in response thereto.
These and other ob;ects of the invention will become ~pparent in light of thn presont speclfioatioD ~=d dravlngs.

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SUMMARY OF THE INVENTION

The present invention comprises a wireless stereo audio/video signal transmitter and receiver system apparatus with remote control capability which is capable of accepting an external baseband stereo audio signal an external baseband video signal from an external audio/video signal source. The wireless stereo/video signal transmitter and receiver system apparatus services to FN modulate a combined stereo audio/video signal which is transmitted on an RF carrier to one or more remote receivers which regenerate the original baseband stereo audio signal and baseband video signal as well as a mono audio/video signal modulated a particular television channel for use by a remote external television or monitor device.
A transmitter is provided for connection to an external audio/video signal source, such as a video cassette recorder (VCR), and is capable of accepting external baseband stereo audio signals and external baseband video signals as inputs to the transmitter. Such inputs are typically provided as RCA jack terminals on the connector portions of the VCR.
The transmitter includes a subcarrier modulator which are electrically connected to the baseband stereo audio signal input. The subcarrier modulator serves to provide pre-emphasis to the stereo audio signals and separately FM modulates the stereo audio signals towards converting the signals to modulated subcarrier audio signals.
A baseband video signal input section is provided ~or permitting an external baseband video qignal source to be connected to the transmitter. A video signal processor is provided and is electrically connected to the baseband video signal input. The video signal processor serves to provide a filtered pre-emphasized video signal output.
A combiner electrically connected to the subcarrier modulator and the video signal processor serves to combine the modulated subcarrier audio signals with the filtered pre-: . . . -.

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2~33~35 emphasized video signal. The combined signal being further processed by the transmitter IF signal processor which is electrically connected to the combiner. The transmitter IF
signal processor serves to frequency modulate a voltage controlled oscillator at 2SO MHz and provides as an output a modulated audio/video signal output.
An up converter is provided and is electrically connected to the combiner and serves to convert the modulated IF
frequency audio/video signal to an RF frequency signal. An RF
amplifier is provided and is electrically connected to the up converter and serves to amplify the RF frequency audio/video signal. Transmitter antenna electrically connected to the RF
amplifier serves to transmit the amplified RF audio/video signal to the receiver.
A receiver is provided which is capable of receiving the amplified RF audio/video signal output of the transmitter antenna towards generating an external modulated mono audio/video signal as well as an external baseband stereo audio signal and baseband video signal output.
Receiver antenna is provided with each receiver for receiving the RF signal transmitted by the transmitter.
Receiver front end, electrically connected to the receiver antenna, serves to amplify and filter the received RF
signal. Down converter, electrically connected to the receiver front end is provided and serves to convert the received RF
audio/video signal to an IF audio/video signal.
Receiver IF signal proces~or is provided and are electrically connected to the down converter. A PLL detector is electrically connected to the receiver IF signal processor and is provided towards demodulating the IF signal output of the receiver IF signal processor towards providing a combined ba~eband video signal and modulated audio subcarrier signal output.
Stereo audio signal demodulator electrically connected to the PLL detector is provided where the stereo audio signal

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demodulator converts the modulated audio subcarrier signals to baseband stereo audio signal outputs. A baseband video signal generator is provided and is electrically connected to the PLL
detector. The baseband video signal generator provides a filtered de-emphasized and amplified baseband video signal output which may be connected to an external television de~ice via baseband video signal output provided and electrically connected to the baseband video signal generator.
Audio/video signal modulator electrically connected to the stereo audio signal demodulator and the baseband video signal generator is provided and serves to generate a modulated composite mono audio/video signal output which corresponds to a particular television channel, in the present example, channel 3 or channel 4. A composite audio/video signal output electrically connected to the audio/video signal modulator permits the modulated composite audio/video signal output to be connected to the external television device.
Further provided is a handheld remote control transmitter capable of controlling the functions of the external audio/video signal source by replacing the standard IR remote control typically provided with such external audio/video signal sources. The handheld remote control unit includes a command entry device which permits the user to enter a command towards actuating a function of the external audio/video signal source as well as command and coding device electrically connected to the command entry device which serves to generate an encoded remote control code sequence depending upon the command entered by the user on the command entry device. Remote controller RF
transmitter is provided and are electrically connected to the command encoding device for generating and transmitting an RF
remote control output signal.
The RF remote control output signal is received by the remote control receiver which in the embodiment disclo9ed herein is housed within the transmitter. Remote control receiver , .., . ~.
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antenna is provided for receiving the actual RF remote control signal from the handheld RF remote control transmitter. Remote control RF receiver and remote control RF detector are provided for respectively receiving the RF remote control signal transmitted by the handheld remote control transmitter and recovering the encoded remote control key code sequence towards providing as an output the encoded remote control key code - sequence. A controller electrically connected to the RF detector is provided together with IR remote control signal transmitter which is electrically connected to the controller. The I~ remote control signal transmitter services to generate an IR remote control signal under the direction of the controller in response to the corresponding RF remote control signal generated by the handheld remote control transmitter and received by the remote control receiver.
An IR command signal receiver is provided for receiving an IR command signal from the external audio/video signal sources standard IR remote control towards programming the controller.
An IR command signal detector ls electrically connected to the IR
command signal receiver and serves to provide the controller with the decoded IR command signal in response to the received RF
command signal.
Accordingly, in operation the wireless audio/video signal transmitter and receiver system apparatus with remote control extender capability permits the wireless transmisaion and remote reception of audio/video signals from a signal source such as a VCR to a reception device auch as a televi~ion monitor and the wireless transmission and remote reception of RF remote control signals from a handheld remote control transmitter ~ towards the regeneration of corresponding IR remote control ; signals towards activating the external audio/video signal source device from the remote location.
; In the preferred embodiment of the invention, the ~, wireless stereo audio/video signal transmitter and receiver system having remote control capability includes baseband stereo . 9 .~

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audio signal input which are comprised of left and right channel baseband audio signal input connectors for accepting connection of the left and right channel external baseband audio signals.
The apparatus further includes baseband video signal inp~t which are comprised of baseband video signal input connectors for accepting connection of the external baseband video signal.
In the preferred embodiment of the invention, the baseband video processor preferably comprises a first baseband video processor buffer, a baseband video processor lowpass filter, a second baseband video processor buffer, a baseband video processor pre-emphasis network, first baseband video processor amplifier, trap, second baseband processor amplifier and video level control all connected in series to the baseband video signal input connector where the baseband video processor serves to remove unwanted frequency components from the baseband video signal and pre-emphasized video signal.
The subcarrier modulator preferably comprises left and right channel pre-emphasis network electrically connected to the baseband stereo audio signal input connectors, which serve to boost high frequency components of the external baseband stereo audio signal towards removing noise components from the signals when later demodulated. Additionally provided are left and right channel baseband audio subcarrier modulator electrically connected to the respective left and right channel pre-emphasi6 network for separately modulating the left and right channel external baseband audio signal6 generating an audio subcarrier signal output $rom each. The subcarrier modulator $urther includes left and right channel audio subcarrier signal buffer electrically connected to the left and right channel baseband audio subcarrier modulator, respectively.

In the pre$erred embodiment of the invention, the combiner comprises an audio signal combiner electrically connected to the left and right channel audio subcarrier buffer towards actively combining and amplifying the left and right , .

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audio subcarrier signals towards providing a combined audio signal output and a video signal combiner electrically connected to the audio subcarrier signal combiner and the video level control for combining and amplifying the input signals towards generating a combined subcarrier audio/video signal.
Additionally, preferably provided is a video clamp electrically connected to the video signal combiner.
- The IF signal processor preferably comprises a voltage controlled oscillator, IF signal processor bandpass filter, variable attenuator, second IF signal processor lowpass filter all connected in series to the combiner, the output of which services to frequency modulate the voltage controlled oscillator thereby generating a modulated audio/video signal.
The RF amplifier of the present invention preferably comprises an RF section bandpass filter electrically connected to the up converter, RF section matching pad electrically connected to the RF section bandpass filter, first RF section amplifier electrically connected to the RF section matching pad, second RF
section amplifier electrically connected to the first RF section amplifier and an RF section lowpass filter electrically connected to the second RF section matching amplifier.
In the preferred embodiment of the invention the receiver front end comprises a first low noise input amplifier, an input bandpass filter and low noise high gain input amplifier all connected in series with one another where the receiver front end serves to amplify and filter the received RF signal.
~ he IF signal processor of the pre9ent invention preferably comprises an AGC amplifier, first receiver IF signal processor amplifier, AGC buffer, AGC detector and second IF
signal processor amplifier all connected in series.
Moreover, in the preferred embodiment of the invention includes a stereo audio signal demodulator which comprises demodulator buffer connected to the PLL detector, left and right channel subcarrier demodulator for separately demodulating the left and right channel audio signals each generating a baseband ` 11 ' ' ' ' ' " ` ' . ' ' ' " . . ' ' .
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audio signal output and left and right channel de-emphasis network electrically connected to the respective left and right channel subcarrier demodulators serving to provide and de-emphasized baseband left and right channel audio signal output.
The baseband video signal generator of the present invention preferably comprises receiver video level control, first video generator amplifier, video generator lowpass filter, first video generator buffer, video generator de-emphasis network, second video generator amplifier and second generator buffer electrically connected in series to the PLL detector and serving to provide a baseband video output signal.
The video signal modulator of the present invention comprises an audio signal combiner electrically connected to the stereo signal demodulator for combining the left and right channel output signals towards creating a mono audio signal, a video signal amplifier electrically connected to the baseband video signal generator, and an audio/video signal modulator electrically connected to the audio signal combiner and the video signal amplifier towards providing a composite mono audio/video signal modulated on a particular television channel. Further provided is a video signal lowpass filter and video signal attenuator connected in series to the audio/video modulator the output of which is provided on a modulated composite audio/video signal output connector.
In the preferred embodiment of the invention, the remote control transmitter transmits said remote control co~mand signals on an RF carrier of 500MHz, though another legally allowed frequenay may be used. The remote control command signals are generated by the remote control transmitter which includes a push-button matrix keyboard for entering such commands. The command are received by the remote control command signal receiver comprises four gain blocks tuned to 50aMHz.
In the preferred embodiment of the invention the IR
remote control signal transmitter comprises a plurality of infra-.

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red emitting LEDs and the IR command signal receiver comprises ainfra-red sensor diode.

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BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 of the drawings is a pictorial representation of the transmitter means, receiver means and remote control extender means comprising the present convention together with the video source for transmission (VCR) and the remote television;

Fig. 2 of the drawings is a block diagram illustrating the functional modules of the transmitter means comprising the present invention;

Fig. 3 of the drawings is a schematic circuit diagram illustrating the baseband stereo audio signal input means, baseband video signal input means, video processor means, subcarrier modulator means and combiner means of the transmitter means of the present invention;

Fig. 4 of the drawings is a schematic circuit diagram illustrating the IF signal proce6sor means and up converter means of the transmitter means of the present invention;

Fig. 5 of the drawings is a schematic circuit diagram illustrating the RF amplifier means and transmitter antenna means of the transmitter means of the present invention;

Fig. 6 of the drawings is a schematic circuit diagram of the power supply circuitry for the transmitter means and the remote control receiver means of the present invention;

Fig. 7 of the drawings is a block diagram illustration of the functional modules of the remote control extender means of the present invention comprising a handheld RF remote control transmitter means and remote control receiver means;

Fig. 8 of the drawings is a floor chart diagram of the logic operation of the handheld RF remote control transmitter means and remote control receiver means of the remote control extender means of the present invention;

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Fig. g of the drawings is a schematic circl~it diagram illustrating the controller means of the remote control receiver means of the remote control extender means of present invention;

Fig. 10 of the drawings is a schematic circuit diagram of the IR transmitter means and the LED display means of the remote control receiver means of the present invention;

Fig. 11 of the drawings is a schematic circuit diagram illustrating the IR receiver means and IR detector means of the present invention;

Fig. 12 of the drawings is a schematic circuit diagram illustrating the RF receiver means of the remote control receiver means of the present invention;

Fig. 13 of the drawings is a schematic circuit diagram illustrating the RF detector means of the remote control means of the present invention;

Fig. 14 of the drawings is a schematic circuit diagram illustrating miscellaneous jumper configurations and capacitance connections of the remote control means of the present invention;

Fig. 15 of the drawings is a bloc~ diagram illustrating the functional modules of the receiver means comprising the present invention;

Fig. 16 of the drawings is a schematic circuit diagram illustrating the receiver antenna means, receiver front end means and down converter means of the receiver means of the present invention;

Fig. 17 of the drawings i~ a schematic circuit diagram ~' illustrating the receiver IF signal processor means of the ,j receiver means of the present invention;

Fig. 18 of the drawings is a schematic circuit diagram illustrating the PLL detector means and stereo audio signal -: .: :, ` ~' .
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demodulator means of the receiver means of the present invention;

Fig. 19 of the drawings is a schematic circuit diagram illustrating the baseband video signal generator means and the audio/video signal modulator means of the receiver means of the present invention;

Fig. 20 of the drawings is a schematic circuit diagram of the power supply circuitry for the receiver means of the present invention.

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DETAILED DESCRIPTION OF THE DRAWINGS

While this invention is susceptible of embodiment in many different forms, there are shown in the drawings and will herein be described in detail a specific embodiment, with the understanding that the present disclosure is to be considered as an exe~plification of the principals of the invention and is not intended to limit the invention to the embodiment illustrated.
Fig. 1 of the drawings is a pictorial representation of the various elements which comprise the present invention 10, namely, transmitter base unit 11, receiver unit 12, RF remote control transmitter 13 and RF remote control receiver.
Additionally, external audio/video signal source 14 which supplies the audio/video signal to be transmitted is illustrated as a VCR together with remote television 15 which in this configuration will display the transmitted audio/video signal.
Audio/Video signal source 14 is shown electrically connected to transmitter base unit 11 via cable 16. Receiver unit 12 is likewise shown electrically connected to remote television 15 via cable 17. In a typical situation, audio/video signal source 14 and transmitter base unit 11 are positioned by the user at a first location. Remote television 15 is typically located at a second location remote from the first location. In operation, audio/video signal source 14 provides a baseband stereo audio/video signal output on cable 16 to transmitter base unit 11 which after processing FM modulates the stereo audio/video signal and transmits the signal on an RF carrier which i~ received at the remote second location by receiver unit 12. Receiver unit 12 in turn regenerates the original stereo audio/video signals and provides baseband stereo audio/video signals on cable 17 to remote television 15. In addition, receiver unit 12 is capable of providing a mono audio/video signal modulated at either channel 3 or channel 4 which may be received by the antenna inputs of remote television 15.
In order to permit the user to actuate the remote .

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control functi~ns of audio/video signal source 14 from the remote second location handheld RF remote control 13 as provided.
Handheld RF remote control transmitter 13 replaces the standard remote control unit provided with video source 14, typically an infra-red (IR) based device. Handheld remote control transmitter 13 is shown incorporating a matrix key pad, a mode select switch (which permits the user to selectively control up to four (4) separate remote audio/video signal sources 14), as well as a "send" indicator which comprises an LED which notifies the user that the handheld RF remote control transmitter 13 is operating when the key pad is pressed. The key pad is shown comprising a plurality of buttons corresponding to those found on typical standard remote control devices and may provide for example, volume control, channel control and direct channel entry control.
Fig. 2 of the drawings is a block diagram illustrating the functional modules of the transmitter 11 of the present wireless stereo audio/video signal transmitter and receiver system apparatus with remote control extender capability 10.
8aseband video signal input connector 21 comprises a connection point for connecting the external baseband video signal to transmitter 11. Baseband video signal output connector 22 is shown electrically connected to buffer 23 which is in turn shown electrically connected to baseband video signal input connector 21. Baseband video input signal connector 21 is thus fed into buffer 23, the output of which i6 the loop-through baseband video signal which permits connection to other electronic deViCes 9Uch as additional VCR's or monitors or the like which may use the baseband video input signal simultaneously with the present invention. Baseband video signal input connectors 21 and baseband video output connector 22 are both preferably RCA type connectors.
Baseband video signal input connector 21 is shown connected to the video processor section of the present ~, `' ~ . , ~

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transmitter. The baseband video signal passes through buffer 24, lowpass filter 25, buffer 26 and video pre-emphasis network 27.
Lowpass filter 25 is a 4.5 MHz lowpass filter. Video pre-emphasis network 27 follows the CCITT 405A specification. After pre-emphasis, the video signal is amplified by amplifier 28 and then passes through trap 29. Trap 29 is a 5.5 MHz trap which serves to remove any video information at 5.5 MHZ that lowpass filter 25 has failed to remove. After trap 29, the baseband video signal is then buffered by buffer 30 after which the signal passes through video level control 43 shown comprising a variable resistor.
Baseband audio signal input connectors 31 and 33 provide a connection point at which an external baseband stereo audio signal comprising left and right channels may be connected to transmitter 11. As illustrated, the left channel is connected to connector 31 and the right channel is connected to connector 33. A direct high impedance loop is associated with both connectors 31 and 33 towards providing left and right baseband audio signal outputs on connectors 32 and 34 respectively.
Connectors 31 through 34 preferably comprise RCA type connectors.
The left and right audio channel signals are separately pre-emphasized by 75 microsecond pre-emphasizers 35 and 36, respectively which form the initial state of the subcarrier modulator section. The left channel audio signal is frequency modulated onto a 5.5 MHZ subcarrier by subcarrier modulator 37 and the right channel audio signal is frequency modulated on a 6.5 MHz subcarrier by ~ubcarrier modulator 38. The le~t and right channel subcarrier signals are then each buffered separately by buffers 39 and 40, respectively, and are shown combined with one another through an active audio signal combiner/amplifier 41.

The output of audio signal combiner/amplifier 41 comprising the combined left and right channel subcarrier signals is combined with the output of video level control 43 by video/subcarrier combiner 42 the output of which is shown passing :' ~33835 through video clamp 44. The IF section of the transmitter unit follows. After the audio and video signals are co~bined by video/subcarrier combiner 42, the combined signal is shown passing to voltage controlled oscillator (VCo) 45. VCO 45 possesses a center frequency of 251.5 MHz wherein the combined video/subcarrier signal serves to frequency modulate VCo 45.
From the output of VCO 45, the signal is shown being fed through an elliptic bandpass filter 46 having a centex frequency of 252 MHz and possesses a bandwidth of 49 MHz. The output of bandpass filter 46 is shown connected to variable attenuator 47 which is controlled by RF level control 48. The signal thereafter passes to lowpass filter 49, a four pole lowpass filter with a cutoff freguency of 300 NHz.
The output of lowpass filter 49 is shown passing to up converter 50 a NEC uPC1685 type device. Up converter 50 is configured to have a fixed LO frequency of 665 MHz which is mixed with the IF signal input centered at 251.5 MHz towards producing RF signal at 916.5 NHz.
The output of up converter 50 then passes to the RF
amplifier section of the transmitter. As shown, the RF signal is fed into a three pole bandpass filter 51 which is centered at 916.5 NHz and has a bandwidth of 15 MHz. Bandpass filter 51 output is fed to resistive pad 52 having a 3dB attenuation. The signal is then shown fed to a hybrid amplifier 53 providing approximately 18 dB gain. The signal thereafter is shown being fed into amplifier 54 which provides 13 dB of gain and thcn into amplifier 55 which provides an additional 13 dB of gain. The output of amplifier 55 i5 shown connected to lowpass filter 56 a three pole lowpass filter with a cutoff frequency of 1 GHz.
The filter 56 output is shown connected to balun 57 which in turn is connected to dipole antenna 58 towards transmitting the modulated RF audio/video signal.
Fig. 3 of the drawings is a schematic circuit diagram illustrating the baseband video signal input means 210, video . , ~ 20 : , ! ' :' ' . ~ ' ' " ~' "' , '~' . :
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2~133~35 processor means 220, basaband stereo audio signal input means 230, subcarrier modulator means 240 and combiner means 250.
The baseband video signal input means 210 is shown comprising external connectors 21 and 22. As illustrated, the baseband video input signal connected to video input connector 21 passes through buffer 23 onto video output connector 22.
Video processor means 220 is shown comprising buffer 24 connected in series with lowpass filter 25. As designed, lowpass filter 25 is effective at trapping signals at 6.5 MNæ but may be less effective at trapping signals at 5.5 MHz. Video processor means 220 further includes the series connection of buffer 26, video pre-emphasis network 27, amplifier 28 (shown comprising a two stage transistor amplifier) and trap 29. As illustrated an designed, trap 29 serves to trap 5.5 MHz signals which may pass through lowpass filter 25. The output of trap 29 passes through buffer 30 and onto video level control 43 shown comprising a variable lK resistor.
Baseband stereo audio signal input means 230 is shown comprising left audio channel input connector 31, right audio channel input connector 33, left audio channel output connector 32 and right audio channel output connector 34. As illustrated, the audio channel inputs 31 and 33 are passed through a direct high impedance loop to output connectors 32 and 34, respectively.
Connectors 31 through 34 preferably comprise RCA type connectors.
AB illustrated, both the left channel audio signal and right channel audio signal pass through circuits which are identical except for the fact that the left audio channel signal ls frequency modulated onto a 5.5 MHz subcarrier by subcarrier modulator 37 and the right audio channel signal is modulated onto a 6.5 MHz subcarrier by subcarrier modulator 38. As shown, subcarrier modulator 37 and 38 comprise LA7053 type IC devices.
The left and right aubcarrier signals are shown buffered by buffers 39 and 40.
The left and right channel subcarrier signals are combined through an audio combiner 41 an active . I .
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combiner/amplifier comprising a type 2N3904 device.
The video/subcarrier combiner 42 is shown formed by a combination emitter follower buffer and constant current source each composed of a type 2N3904 transi~tor device. The low impedance output of video/subcarrier combiner 42 is shown passing through video clamp 44 which is based upon a type lN4148 diode device. Video clamp 44 holds the DC level of the signal constant regardless of the average picture level (APL) and serves to keep the VC0 45 centered.
Fig. 4 of the drawings is a schematic circuit diagram illustrating IF signal processor 260 and up converter 270. IF
signal processor 260 is shown including voltage controlled oscillator (VCo) 45 which has a center frequency of 251.5 MHz.
The combined video/subcarrier signal serves to frequency modulate VC0 45 to a maximum peak to peak deviation of approximately 5 MHz. VC0 45 is shown including free running oscillator operating at 25}.5 MHz and based upon a BFR92A transistor.
The output of VC0 45 is fed through an elliptic bandpass filter 46 having a center frequency of 252 NHz and a bandwidth of 40 NHz. The output of bandpass filter 46 is shown connected to a PIN diode attenuator 47 which has a control range of +/- 5dB on the IF signal at 252 MHz. Control is shown accomplished by variable resistor 48. RF level control is provided by the combination of variable resistor 48 and the type HP3080 diode 47 together with flanking RC networks. The output of attenuator 47 is shown passing through a four pole lowpass filter 49 whiah has a cutoff frequency of 300 MHz.
Up converter section 270 is shown prlncipally comprising up converter 50 an NEC uPC1695 device togather with support componentry. Up converter 50 is shown configured to have a fixed L0 frequency OL 665 MHz which when mixed with the incoming IF signal centered at 251.5 MHz serves to produce an RF

signal at 916.5 MHz.
The RF output signal of up converter 50 is shown . . .

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2~3~35 connected to a three pole bandpass filter 51. Bandpass filter 51 is centered at 916.5 MHz and has a bandwidth of 15 MHz. As illustrated, filter 51 is formed by three tuned, coupled, short circuited microstrip line sections. The output of filter 51 is fed into a resistive PAD 52 having a 3dB attenuation.
Fig. 5 of the drawings is a schematic circuit diagram illustrating the RF amplifier 280. The output of PAD 52 is shown connected to amplifier 53 which as illustrated is a hybrid amplifier having approximately 18dB gain. The signal is then shown fed into two consecutive transistor amplifier stages, amplifiers 54 and 55. Both amplifiers are identical in design and are built around the NEC NE85639 RF transistor. Amplifiers 54 and 55 each provide a gain of 13 dB. The output of amplifier 55 is fed into a three pole lowpass filter 56 with a cutoff frequency of 1 GHz and is shown comprising a microstrip line device. The output of Filter 56 is connected to dipole antenna 58 a 1/2 wave antenna via a 3/4 wave section of RG178 coax cable.
The coax cable acts as both a balun S7 for the antenna as well as part of the antenna matching network.
Fig. 6 of the drawings illustrates the schematic diagram for the power supply for the transmitter 11. Transmitter 11 is designed to accept a filtered unregulated DC input which may be provided from an external power adapter. The loaded DC
voltage from such an adapter is approximately 14.5 Vdc. The unregulated voltage is internally regulated to +12 volts and to +5 volts. The unregulated voltage is also provided on a four pin connector to supply power to the remote control receiver which i~
housed withln the same cabinet as the transmitter 11. The operation of power supply illustrated in Fig. 6 of the drawings ~I should be readily discernible to those skilled in the art.
Fig. 7 of the drawings is a block diagram illustration of the functional modules of the remote control transmitter and remote control receiver of the present wireless stereo audio/video signal transmitter and receiver system apparatus With remote control extender capability. Hand-held remote control - : - : : ~. . . : :

2!~3383~

transmitter 13 is shown comprising keyboard 60 which is electrically connected to encoder 61 which is in turn electrically connected to RF transmitter 62. Keyboard 60 is preferably a matrix keypad which resembles the standard infrared (IR) remote control device typically supplied with a VCR and the like and possesses prelabled buttons corresponding to such functions as volume, channel and the like. Encoder 61 comprises a combined keypad scanner and key code encoder which translate actuation of the keyboard 60 into a key code wherein different key code sequences are ~enerated depending upon which key of the keyboard 60 is depressed. RF transmitter 62 serves to amplitude modulate the key code data on an RF carrier centered at 500 MHz.
As contemplated, handheld RF remote control transmitter 13 may include a device select switch that allows selection between one of four different remote controls whose key codes have been programmed into the remote control receiver.
As an overview of the interaction between handheld RF
remote control transmitter 13 and remote control receiver 19, the following is provided. The present apparatus is operated by first "teaching" the remote control receiver 19 the IR key codes for the various IR remote controls 18 associated with the external audio/video signal source 14 and then "assigning" the key codes to the corresponding key codes transmitted from the handheld RF remote control transmitter 13.
The "teaching" is accomplished by placing remote control receiver 19 into a "learn" mode via switch provided. In the "learn" mode the user i5 prompted by LED indicators to slmultaneous press a key on IR remote control 18 and a corresponding key on handheld RF remote control transmitter 13 to which the user wishes to assign the particular key function.
This process is repeated until all the keys are entered.

I Thereafter, remote control receiver 19 i9 switched back to a ! "normal" mode. once taught, remote control receiver 19 will regenerate and emit the identical IR code it has learned when it : . . ~ :: ' . :

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receives the corresponding RF key code transmitted by handheld remote control RF transmitter 13.
Remote control receiver 19 contains RF receiver 63 which receives the RF signal transmitted from handheld RF remote control transmitter 13 at 500 MHz. The output of RF receiver 63 is shown connected to RF detector 64 which recovers the amplitude modulated data encoded by handheld RF remote control transmitter 13. The recovered key code data is shown connected to controller 65 a microprocessor based device. IR transmitter 66 i shown electrically connected to controller 65 and serves to generate the IR signal in response to handheld RF remote control transmitter 13 which IR signal services to actuate the various functions of controlled device 14.
When in the "learn" mode, controller 65 reads the IR
code data generated by standard remote control 18 and stores the IR code in controller memory. It simultaneously stores in memory the corresponding RF remote control transmitter key code. When in the "normal" mode, the contro}ler 65 detects the RF key code transmitted from handheld RF remote control transmitter 13 and looks into its memory for the corresponding IR code. This IR
code is then retrieved and sent out through an array of IR
emitter diodes. IR receiver 67 is shown and is provided for receiving the IR signal from the standard remote control 18. IR
detector 68 serves to detect the information key code transmitted and feeds the key code data to controller 65 as illustrated in the "learn" mode.
Fig~ 8 of the drawings is a flow chart diagram of the logical operation per$ormed by handheld RF remote control transmitter 13 and remote control receiver l9 of the present invention. The logic of this chart and its operation should be readily discernible to those skilled in the art having before them the present disclosure and description of operation.

Fig. 9 of the drawings is a schematic circuit diagram illustratins the controller 65 of remote control receiver 19.
Controller 65 is based primarily upon a type M50747 device a ,~: : : ,~ - : :

2~33835 "microprocessor~ on a chip incorporating a microprocessor, RAM
and ROM.
Fig. 10 of the drawings illustrates IR transmitter 66 and the LED display of remote control receiver 19 of the present invention. IR transmitter 66 is shown comprising a plurality of infrared emitting LED's. LED's 80, 81 and 82 are visible light T.~D~5 and serve to prompt the user in the operation of remote control receiver 19.
Fig. 11 of the drawings is a schematic circuit diagram of IR receiver 67 and IR detector 68 of the remote control receiver 19. IR receiver 67 is based upon a type 8406HONEY
infrared diode which serves to receive the infrared key codes transmitted by the standard remote control 18. The output of IR
detector 68 comprises the key code sequence corresponding to the particular key depressed upon standard remote control 18.
Fig. 12 of the drawings is a schematic circuit diagram illustrating RF receiver 63 of the remote control receiver 19.
The RF receiver 63 is shown comprising four gain blocks tuned to 500 MHz, the frequency at which the handheld RF remote control transmitter operates. The maximum field strength allowed for this type of operation is 12.5 mV/m at three meters. With this field strength, the resulting received signal level at the remote control receiver is less than -70dBm when operating at a distance of 100 feet. The RF receiver 63 is thus designed to be very sensitive and may alternatively comprise a super-regenerative type receiver.
Fig. 13 of the drawings illustrates RF detector 64 of the remote control receiver 19. As previously described, power for the remote control receiver 19 is provided by the power supply circuitry contained within transmitter 11. Fig. 14 of the drawings illustrates miscellaneous capacitance connections associated with controller 65.
Fig. 15 of the drawings is a block diagram illustrating the functional modules of the receiver 12 of the - , , ~
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, present wireless stereo audio/video signal transmitter and receiver system apparatus with remote control extender capability. Receiver 12 uses an external UHF loop antenna 90 that is shown connected to the RF input section via a 3/4 wave section of RG178 coaxial cable which serves as balun 91 as well as part of the matching network for the antenna.
From the output of balun 91, the received RF signal is shown coupled to low noise amplifier 92 built around the NEC
NE85639 RF transistor. The amplifier 92 has a noise figure of approximately 2.OdB and thus is the dominant factor in determining the overall receiver noise figure. From the output of low noise amplifier 92, the RF signal is fed through a two pole bandpass filter 93 centered at 916.5 MHz having a bandwidth of 20 MHz. The filter output is shown fed to a second low noise amplifier 94 identical in configuration to first low noise amplifier 92.
The output of low noise amplifier 94 is shown connected to down converter 95 which is formed by an NEC uPC1685 type device configured to have variable LO frequency centered at 846.5 MHZ with a control range of +/-15 MHz. The resulting IF signal from mixing the RF signal at 916.5 MHz with the LO signal at 846.5 M~z is an IF signal at 70 MHz.
Fro~ the IF signal output of down converter 95 tha signal is applied to the input of AGC amplifier 96 which provides a maximum of 25 dB of gain at 70 MHz. The output of AGC
amplifier 96 is shown connected to IF amplifier 97 which provides a fixed gain of 25 d~, the output of which is conneated to buffer 98 and in turn to bandpass filter 101 a three pole bandpass filter centered at 70 MHz having a bandwidth of 20 MHz.
The signal from buffer 98 is shown also connected to the input RF detector 99. The output of RF detector 99 is a dc level proportional to the RF carrier amplitude of the input signal and is fed to the AGC control of AGC amplifier 96 via a control amplifier lOO. The AGC loop defined by amplifiers 96 and 97, buffer 98, detector 99 and amplifier 100 serves ta keep the '~` , . ' ' ' '. ' .' ' :

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RF level input to PLL detector 102 constant at -14 dBm.
The output of bandpass filter 101 is shown fed to the input of PLL detector 102. The output of PLL detector 102 is a combined pre-emphasized video/audio subcarrier signal similar to that which was fed to the input of VC0 45 in transmitter 11.
From the PLL 102 detector output, the signal is shown splitting into three separate signal paths. The first path is to the AFC control amplifier 104. The AFC control signal derived from the output of PLL detector 102 acts to maintain a stable IF
frcquency. The second path from PLL detector 102 is to buffer 105 which forms the initial stage of the subcarrier demodulator section of the receiver 12. The third signal path is to a video level controlled potentiometer 115 forming the initial part of the baseband video signal generator.
The stereo audio signal demodulator section begins with buffer 105 the output of which is shown connected to two subcarrier bandpass filters. Filter 107 is centered at 5.5 MHz for the left audio channel subcarrier and bandpass filter 106 is centered at 6.5 MHz for the right channel subcarrier signal. The outputs of filters 106 and 107 are shown connected to subcarrier demodulators 108 and 109, respectively, where subcarrier demodulators 108 and 109 are identical except that demodulator 108 is tuned for 6.5 MHz while demodulator 109 is tuned for 5.5 NHz corresponding to the right and left channels respectively.
The outputs of demodulators 108 and 109 are pre-emphasized baseband audio aign41s are thus are shown connected to audlo de-empha~izers 1}0 and 111, respectively. The de-emphasized left and right audio signals are provided to the user through baseband audio output connectors 113 and 114 corresponding to left and right channels respectively and preferably comprise RCA type connectors.

The output of video level control 115 is shown connected to a amplifier 116 and then to a three pole lowpass filter 117 having a cutoff of 4.5 MHz. From the output lowpass - - . .

, filter 117, the signal is buffered by buffer 118 and is shown fed to the input of a video de-emphasis network 119. The video de-emphasis network 119 follows the CCITT 405A specification. From the output of de-emphasis network 119, the signal is fed to amplifier 120 and then to buffer 121 which provides as an output a baseband video signal which is provided to the user through an RCA type connector 122. The video output level is lVpp.
Audio signal combiner 112 is shown connected to the outputs of audio de-emphasizers 110 and 111 and serves to combined the left and right channel audio signals into a single mono signal. The output of amplifier 120 is shown connected to amplifier 123. The combined mono audio signal and the baseband video output of amplifier 123 are shown connected to modulator 124 which is a self contained AM TV modulator IC type MC1374 and serves to modulate the two input signals to an AM double side band format with a frequency modulated audio subcarrier at 4.5 MHz. Modulator 124 is selectable between television channel 3 and television channel 4 having carrier frequencies of 61.25 MHz and 67.25 MHz respectively. The output of modulator 124 is shown connected to a five pole lowpass filter 125 having a cutoff frequency of 70 MMz. From filter 125, the signal is fed to 20dB
attenuator 126 and lastly to composite modulated signal output connector 127 where the RF output level is -42dBm.
Receiver front end 310 is illustrated in schematic representation in Fig. 16 of the drawings. Receiver front end 310 accepts a RF input from an external UHF loop antenna which is connected via a 3/4 wave section of RG178 coaxial cables serving as a balun, (not shown). From the output of the balun, the signal is coupled to an antenna matahing component network formed by the capacitor and microstrip line device illustrated. The signal is then fed to the input of a low noise transistor amplifier 92 built around the NEC NE85639 RF transistor. This amplifier has a noise figure of approximately 2.OdB and is the dominant factor in determining the overall receiver noise figure.
The output of low noise amplifier 92 is shown connected to a two , - . : . - . : .

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pole bandpass filter 93. Filter 93 is centered at 916.5 MH7 and has a bandwidth of 20 MHz, and is formed by two tuned coupled short circuited microstrip line sections. The output of filter 93 is fed to a second low noise amplifier 94 which is identical in configuration to low noise amplifier 92.
Down converter section 320 is shown formed principally by an NEC uPC1685 type device. Down converter 95 is configured to have a variable LO frequency centered at 846.5 MHZ with a control range of +/-15 MHz. The resulting IF output from mixing the inpUt RF signal at 916.5 MHz with the LO signal at 846.5 MHz i8 an IF signal at 70 MHz. The frequency adjustment is accomplished via a DC voltage applied to a UHF varactor diode in the LO tank circuit as illustrated. This adjustment is provided to compensate for component tolerances. In addition to the frequency adjustment, a second varactor is used in the LO tank circuit to provide a control means for the AFC signal. The AFC
control signal acts to maintain a stable IF frequency over a range of +/-5 MHz. AFC control section 330 is illustrated in `Fig. 16 and comprises an AFC control amplifier formed by two LM358 type devices the input of which is derived from the output of the PLL detector 102.
Fig. 17 of the drawings is a schematic circuit diagram of receiver IF signal processor section 340 of receiver 12. As illustrated, the input to receiver IF signal processor 340 comes from the output of down converter 95. The IF output of down converter 95 is applied to the input of an AGC (Automatic Gain Control) amplifier 96 which is formed by an MC1350P device and provides 25dB of gain at 70 MHz. Amplifier 96 can provide up to 60dB of AGC through a DC control signal applied to PIN 5 as illustrated.
The output of AGC amplifier 96 is shown connected to IF

amplifier 97 which is an amplifier chain made up of three cascaded common emitter amplifiers each type 2N3904 devices the output of which is connected to buffer 98 an emitter follower ,:

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buffer. From the output of buffer 98, the signal is fed to the input o~ a three pole bandpass filter 101 which is centered at 70 MHz and has a bandwidth of 20 MHz.
The signal output from buffer 98 is also fed to the input of an RF detector 99 which is formed by a 100 pico farad capacitor together with a HP2800 device. The output of PF
detector 99, which is dc level proportional to the RF carrier amplitude, is fed to PIN S of AGC amplifier 96 via a control amplifier 100 which is formed by two LN358 devices. The action of this AGC loop serve~ to keep the RF level at the input to PLL
detector 102 constant at -14 dBm.
Fig. 18 of the drawings illustrates a schematic circuit diagram for PLL detector section 350 and stereo audio signal demodulator section 360. The output of the 70 MHz bandpass filter 101 is shown connected to the input of a PLL detector 102.
The output of PLL detector 102 is a combined pre-emphasized video/audio subcarrier signal similar to what was fed to the input of VC0 45 of transmitter 11. The output of PLL detector 102 on PIN 14 is a demodulated output comprising pre-emphasized baseband audio signals combined and baseband video. From the output of PLL detector 102, the signal splits off into three separate signal paths. The first path is to the AFC control amplifier section 330. The second path is to buffer 105 forming the initial stage of the stereo audio signal demodulator section 360. The third path is to video level control potentiometer llS
forming the initial stage of the baseband video signal generator 370.
From the output of PLL detector 102, the signal passes to buffer lOS the output of which splits and is applied to the input of two subcarrier bandpass filters 106 and 107. 3andpass filter 106 is centered at 6.5 MHz for the right channel subcarrier and bandpass filter 107 is centered at 5.5 NHZ for the left channel subcarrier. The outputs of bandpass filters 106 and 107 are applied to two separate subcarrier demodulators 108 and 109 respectively for the right and left channels respectively.

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The two subcarrier demodulators 108 and 109 are identical except that one is tuned for 6.5 MHz and the other is tuned for 5.5 MHz.
The output from the subcarrier demodulators 108 and 109 is pre-emphasized baseband audio. The baseband audio signals are then de-emphasized through audio de-emphasizers 110 and 111 each based upon an LM324 device. The de-emphasized left and right audio signals are shown provided to the user through RCA
connectors 113 and 114. The audio output level is lVpp into a 600 Ohm load from a 600 Ohm source.
Further shown in Fig. 18 is audio signal combiner 112 the inputs to which come from the outputs of de-emphasizers 110 and 111. Audio signal combiner 112 serves to combine the left and right audio siqnals to form a mono audio signal used in the channel 3/4 modulator 124.
Fig. 19 of the drawings is a schematic circuit diagram illustrating the baseband video signal generator 370 and audio/video signal modulator 380. The initial stage of the baseband video signal generator 370 is formed by video level control potentiometer 115 shown as a variable resistor. The signal is then fed into two stage transistor amplifier 116 and then to a three pole lowpass filter 117 having a cutoff of 4.5 NHz. From the output of lowpass filter 117, the signal is buffered by buffer 118 and fed into the input of video de-emphasis network 119 which follows the CCITT 405A specification.
The output of video de-emphasis network 119 is fed into two stage amplifier 120 based upon the 2N3904 and 2N3906 transistors and then onto a emitter follower buffer 121. The buffered baseband video signal output is provided to the user through an RCA
connector 122. The video output level is lVpp.
Audio/video signal modulator 380 comprises a self contained AN TV modulator 124 which accepts the combined audio signal from the audio signal combiner 112 as well as the baseband video output source which is shown tapped off amplifier 120 as further amplified by amplifier 123. Modulator 124 modulates the ;J`'~
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input signals to an AM double side band format with a frequency modulated audio subcarrier at 4.5 MHz. The video depth of modulation is set at 87.5%. The channel selection is made via a switchable DC voltage applied to a varactor diode shown in the oscillator tank circuit. The channel 3 carrier frequency is 61.25 NHz and the channel 4 carrier frequency is 67.25 MHz. The RF output of the modulator is fed to five pole lowpass filter 125 having a cutoff frequency of 70 MHz. From the filter output, the signal is fed to 20dB attenuator 126 and then finally out to the user via an "F" connector 127. The RF output level is -42d8m.
Fig. 20 of the drawings is the power supply circuitry for the receiver 12 of the present invention lO. The operation and function of which is readily discernible to those skilled in the art.
The foregoing description and drawings merely explain and illustrate the invention and the invention is not limited thereto, except insofar as the appended claims are so limited and those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

:

,

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed, are defined as follows:

A wireless stereo audio/video signal transmitter and receiver system apparatus with remote control extender capability capable of accepting external baseband stereo audio and video signal inputs from an external audio/video signal source, wherein the transmitter transmits an audio/video signal to a remote receiver which regenerates the original audio/video signal providing both baseband stereo audio and video signal outputs, as well as a mono audio/video signal output modulated at a particular television channel, for use by a remote external device, and wherein a remote control transmitter and remote control receiver which serves to replace the standard remote control unit provided with the external audio/video source, said wireless audio/video signal transmitter and receiver system comprising:
- transmitter means for connection to said external audio/video signal source and capable of accepting external baseband stereo audio signal and baseband video signal inputs, said transmitter means including:
- baseband stereo audio signal input means for permitting the left and right stereo audio channel signals of said external baseband stereo audio/video signal source to be connected to said transmitter means;
- subcarrier modulator means electrically connected to said baseband stereo audio signal input means, said subcarrier modulator means serving to provide pre-emphasis to said stereo audio signals and modulate said stereo audio signal towards converting said signals to modulated subcarrier stereo audio signals;
- baseband video signal input means for permitting the baseband video signal of said external baseband audio/video signal source to be connected to said transmitter means;
- video signal processor means electrically connected to said baseband video signal input means, said video signal processor means providing a filtered pre-emphasized video signal output;
- combiner means electrically connected to said subcarrier modulator means and said video signal processor means for combining said filtered video signal and said modulated subcarrier stereo audio signals;
- transmitter IF signal processor means electrically connected to said combiner means, said IF signal processor means serving to provide a modulated IF audio/video signal output;
- up converter means electrically connected to said combiner means for converting said modulated IF audio/video signal to an RF audio/video signal;
- RF amplifier means electrically connected to said up converter means for amplifying said RF audio/video signal;
- transmitter antenna means electrically connected to said RF amplifier means for transmitting said amplified RF
audio/video signal;
- one or more receiver means capable of providing an external baseband stereo audio signal and baseband video signal outputs, as well as external modulated mono audio/video signal output, said one or more receiver means each including:
- receiver antenna means for receiving said RF
audio/video signal transmitted by said transmitter means;
- receiver front end means electrically connected to said receiver antenna means for amplifying and filtering said received RF audio/video signal;
- down converter means electrically connected to said receiver front end means, said down converter means serving to convert said received RF audio/video signal to an IF
audio/video signal;

- receiver IF signal processor means electrically connected to said down converter means;
- PLL detector means electrically connected to said receiver IF signal processor means, said PLL detector means serving to demodulate said IF audio/video signal providing a combined baseband video signal and modulated subcarrier audio signal output;
- stereo audio signal demodulator means electrically connected to said PLL detector means, said stereo audio signal demodulator means serving to convert said modulated subcarrier audio signals to baseband stereo audio output signals;
- baseband audio signal output means electrically connected to said audio signal demodulator means for permitting said baseband stereo audio signal output to be connected to a a remote external device;
- baseband video signal generator means electrically connected to said PLL detector means, said baseband video signal generator means serving to provide a filtered, preemphasized and amplified baseband video signal output signal;
- baseband video signal output means electrically connected to said baseband video signal generator means for permitting said baseband video signal output to be connected to a remote external device;
- audio/video signal modulator means electrically connected to said stereo audio signal demodulator means and said baseband video signal generator means, said audio/video signal modulator means serving to provide a modulated composite audio/video signal output corresponding to a particular television channel;
- composite audio/video signal output means electrically connected to said audio/video signal modulator means permitting said modulated composite audio/video signal output to be connected to a remote external device;
- handheld remote control unit means capable of controlling the functions of said external audio/video signal source, said handheld remote control unit means including:

- command entry means permitting the user to enter a command toward actuating a function of said external audio/video signal source;
- command encoding means, electrically connected to said command entry means, said command encoding means serving to generate an encoded remote control key code sequence depending upon the command entered by the user on the command entry means:
- remote control RF transmitter means for generating and transmitting a RF remote control output signal;
- remote control receiver means for receiving said remote control RF signal, said remote control receiver means including:
- remote control receiver antenna means:
- remote control command signal receiver means electrically connected to said remote control receiver antenna means for receiving said RF remote control signal transmitted by said handheld remote control transmitter means;
- remote control RF detector means electrically connected to said remote control command signal receiver means for detecting said received RF remote control signal and recovering said encoded remote control key code sequence and providing as an output said encoded remote control code sequence;
- controller means electrically connected to said RF detector means;
- IR remote control signal transmitter means electrically connected to said controller means, said IR remote control signal means serving to generate an IR remote control signal at the direction of said controller means in response to the corresponding RF remote control signal generated by said handheld remote control transmitter means;
- IR command signal receiver means for receiving an IR command signal from said external audio/video signal source's standard IR remote control unit towards programming said controller means;

- IR command signal detector means electrically connected to said IR command signal receiver means and said controller means, said IR command signal detector serving to provide to said controller means a decoded IR command signal in response said received IR command signal;
- whereby said wireless audio/video signal transmitter and receiver system apparatus with remote control extender capability permits the wireless transmission of audio/video signals from said external signal source and RF remote control signals from said handheld remote control transmitter means toward the remote reception of said audio/video signals and remote control signals toward the regeneration of said audio/video signals and corresponding IR remote control signals.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said baseband stereo audio signal input means comprises:
- left and right channel baseband audio signal input connectors for accepting connection of said left and right channel external baseband audio signals.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said baseband video signal input means comprises:
- baseband video signal input connector for accepting connection of said external baseband video signal.

The wireless audio and video signal transmitter and receiver system according to Claim 1 wherein said baseband video processor means comprises:
- first video processor buffer, first video processor lowpass filter, second video processor buffer, video processor preemphasis network, first video processor amplifier, trap, second video processor amplifier and video level control all connected in series to said baseband video signal input means, said baseband video processor serving to remove unwanted frequency components from said baseband video signal and pre-emphasized video signal.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said subcarrier modulator means comprises:
- left and right channel pre-emphasis network means electrically connected to said baseband stereo audio signal input means, said left and right channel pre-emphasis network means serving to boost high frequency components of said external baseband stereo audio signals toward removing noise components from said signals when later demodulated;
- left and right channel baseband audio subcarrier modulator means electrically connected to said left and right channel pre-emphasis network means, respectively, for separately modulating said left and right channel external baseband audio signals with each left and right channel baseband audio subcarrier modulator means generating an audio subcarrier signal output; and - left and right channel audio subcarrier signal buffer means electrically connected to said left and right channel baseband audio subcarrier modulator means, respectively, each buffer means providing as an output an audio subcarrier signal.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 5 wherein said combiner means comprises:
- audio signal combiner means electrically connected to said left and right channel audio subcarrier signal buffer means for actively combining and amplifying said left and right audio subcarrier signals, said audio signal combiner means providing a combined audio signal output;
- video signal combiner means electrically connected to said audio signal combiner means and said video signal processor means for combining and amplifying said combined audio signal and said processed video signal; and - video clamp means electrically connected to said video signal combiner means.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said IF signal processor means comprises:
- voltage controlled oscillator means, IF signal processor bandpass filter means, variable attenuator means, and second IF signal processor lowpass filter means connected in series to said combiner means, the output of said combiner means serving to frequency modulate said voltage controlled oscillator means the output of which is in turn a modulated audio/video signal.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said up converter means utilizes a fixed local oscillator to convert said modulated IF audio/video signal to an RF signal.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said RF amplifier means comprises:
- RF section bandpass filter, RF section matching pad, first RF section amplifier, second RF section amplifier and RF
section lowpass filter electrically electrically connected in series to said up converter means.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim l wherein said receiver front end means comprises first low noise input amplifier means, input bandpass filter means and second low noise amplifier, electrically connected in series, said receiver front end means serving to amplify and filter said received RF audio/video signal.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said receiver IF signal processor means comprises AGC amplifier, first receiver IF signal processor amplifier, AGC buffer, AGC detector and second IF signal processor amplifier electrically connected in series.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said stereo audio signal demodulator means comprises:
- demodulator buffer means electrically connected to said PLL detector means;
- left and right channel subcarrier demodulator means electrically connected to said demodulator buffer means for separately demodulating said left and right channel audio signals with each left and right subcarrier demodulator means generating a baseband audio signal output;
- left and right channel de-emphasis network means electrically connected to said left and right channel subcarrier demodulator means, respectively.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said baseband video signal generator means comprises:
- receiver video level control means, first video generator amplifier means, video generator lowpass filter means, first video generator buffer means, video generator deemphasis means, second video generator amplifier means, and second video generator buffer means electrically connected in series to said PLL means, said video generator means serving to provide a baseband video output signal.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said baseband video signal modulator means comprises:
- audio signal combiner means electrically connected to said stereo signal demodulator means for combining said left and right channel output signals to create a mono audio signal;
- video signal amplifier means electrically connected to said baseband video signal generator means;
- audio/video signal modulator means electrically connected to said audio signal combiner means and said video signal amplifier means, said audio/video signal modulator means providing an composite mono audio/video signal on a particular television channel;
- video signal lowpass filter means and video signal attenuator means electrically connected in series to said audio/video modulator means;
- modulated composite audio/video signal output connector electrically connected to said video signal attenuator means for permitting connection of said modulated composite audio/video signal to an external device.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said remote control transmitter means transmits said remote control command signals on an RF carrier of 500MHz.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said command entry means comprises a push-button matrix keyboard.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said remote control command signal receiver comprises four gain blocks tuned to 500MHz.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to Claim 1 wherein said IR remote control signal transmitter means comprises a plurality of infra-red emitting LEDs.

The wireless stereo audio/video signal transmitter and receiver system having remote control capability according to

Claim 1 wherein said IR command signal receiver means comprises a infra-red sensor diode.