Abstract:
A wireless output system for AV (audio and/or video) equipment, comprises a base unit for use with the equipment and an output unit for use elsewhere, the two units being communicable with each other via a wireless link. The base unit transmits a wireless AV signal corresponding to an AV signal received from the equipment for reception by the output unit, receives a wireless control signal from the output unit, and transmits a wireless control signal based on the one received for reception by the equipment. The output unit receives the wireless AV signal from the base unit and reproduces sound/image based on the received signal, receives a wireless control signal from a remote controller for the equipment, and transmits a wireless control signal corresponding to the one received for reception by the base unit.

Description:
[0001]     The present invention relates to a wireless output system for use with audio and/or video (AV) equipment, such as CD or TV/DVD players.  
       BACKGROUND OF THE INVENTION  
       [0002]     Remote output systems are generally known especially in the field of audio equipment, such as cordless speakers or headphones. In a typical arrangement, a base receives an audio signal from an audio source and then transmits the signal via infrared or radio frequency, for example, to one or more remote speakers for reproducing the sound, music or the like. These systems are invariably designed for non-interactive, listening purpose alone.  
         [0003]     The present invention seeks to provide a new or improved wireless output system that interacts with the source for enhanced functionality.  
       SUMMARY OF THE INVENTION  
       [0004]     According to the invention, there is provided a wireless output system for use with audio and/or video equipment with an associated remote controller, which system comprises a base unit for use with the equipment and an output unit for use at a remote location, the two units being communicable with each other via a wireless link. The base unit comprises an input for connection to the equipment for receiving an audio and/or video signal therefrom, a first transmitter for transmitting a wireless audio and/or video signal corresponding to the audio and/or video signal received at the input, for reception by the output unit, a receiver for receiving a wireless control signal from the output unit, and a second transmitter for transmitting a wireless control signal based on the wireless control signal received by the receiver, for reception by the equipment. The output unit comprises a first receiver for receiving the wireless audio and/or video signal from the base unit, an output device for reproducing sound and/or image based on the wireless audio and/or video signal received by the first receiver, a second receiver for receiving a wireless control signal from the remote controller, and a transmitter for transmitting a wireless control signal corresponding to the wireless control signal received by the second receiver, for reception by the base unit.  
         [0005]     Preferably, the wireless link for communication between the base unit and the output unit comprises a radio frequency link.  
         [0006]     Preferably, the wireless link for communication between the base unit and the output unit comprises a digital radio frequency link.  
         [0007]     Preferably, the wireless link for communication between the base unit and the output unit comprises a full duplex radio frequency link.  
         [0008]     More preferably, the wireless link is based on a frequency substantially of 5.8 GHz.  
         [0009]     In a preferred embodiment, the second receiver of the output unit comprises an infrared receiver for receiving an infrared control signal from the remote controller, and the second transmitter of the base unit comprises an infrared transmitter for transmitting substantially the same infrared control signal to the equipment.  
         [0010]     More preferably, the second transmitter of the base unit comprises a plurality of infrared light emitting diodes arranged to cover substantially all angular directions.  
         [0011]     In a preferred embodiment, the output unit includes a speaker and a volume control circuit associated with the speaker for operation to control the volume of the sound generated by the speaker based on the wireless audio signal received by the first receiver, according to the wireless control signal received by the second receiver.  
         [0012]     More preferably, the wireless audio signal for the operation of the volume control circuit comprises volume up, volume down and mute signals.  
         [0013]     More or further more preferably, the output unit includes a learning circuit associated with the second receiver for learning and later recognizing the wireless control signal for the operation of the volume control circuit, and a memory for saving data of the learnt wireless control signal.  
         [0014]     It is preferred that the output device comprises a display screen with speaker for reproducing images and sound originated from the equipment.  
         [0015]     It is further preferred that the audio signal from said equipment includes at least one of text data and image data, and the output unit is adapted to process and display said at least one of text data and image data on the display screen. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0016]     The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which:  
         [0017]      FIG. 1  is a schematic circuit diagram of a first embodiment of a wireless output system in accordance with the invention, the system having a base unit and an output unit;  
         [0018]      FIG. 2  is a front view of the base unit of  FIG. 1 ;  
         [0019]      FIG. 3  is a rear view of the base unit of  FIG. 2 ;  
         [0020]      FIG. 4  is a schematic functional block diagram of the base unit of  FIG. 1 ;  
         [0021]      FIG. 5  is a front view of the output unit of  FIG. 1 ;  
         [0022]      FIG. 6  is a top plan view of the output unit of  FIG. 5 ;  
         [0023]      FIG. 7  is a schematic functional block diagram of the output unit of  FIG. 1 ;  
         [0024]      FIG. 8  is a schematic operation flow diagram illustrating an IR control learn function of the output unit of  FIG. 1 ;  
         [0025]      FIG. 9  is a schematic operation flow diagram illustrating IR repeat and remote control functions of the output system of  FIG. 1 ;  
         [0026]      FIG. 10  is a schematic functional block diagram of a base unit of a second embodiment of a wireless output system in accordance with the invention; and  
         [0027]      FIG. 11  is a schematic functional block diagram of an output unit of the second output system. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0028]     Referring initially to FIGS.  1  to  7  of the drawings, there is shown a first wireless output system embodying the invention, which is a wireless speaker system for use with audio equipment/source  10 , such as a MP3 player, placed in the lounge for example and an IR (infrared) remote controller  20  associated with the equipment  10 . The speaker system consists of a base unit  100  for use in front of and preferably adjacent the audio equipment  10  and a speaker unit  200  for use at a remote location such as in the master bedroom. The two units  100  and  200  are designed to co-operate and communicate with each other in a wireless manner, preferably via a wireless digital RF (radio frequency) link tuned at a frequency of 5.8 GHz  
         [0029]     The base unit  100  has a generally spherical housing  110  that includes a flat bottom  111  for standing, a transparent or translucent top  112  and a rear recess  114 . Three IR LEDs  113  are located symmetrically inside the housing  110  for emitting an IR control signal out through the top  112 , 360° around the housing  110  i.e. all angular directions for full coverage. There are five sockets  115  located in the recess  114 , namely a DC power jack  115 A for AC/DC connection and two stereo jacks  115 B and a pair of left/right line-in RCA sockets  115 C for connection of up to three audio sources  10 , such as TV, DVD, CD and/or MP3 equipment, to receive stereo audio signals therefrom. Internal DC battery power operation is possible.  
         [0030]     Provided in the housing  110  is an electronic operating circuit  120  for the base unit  100 , which incorporates an audio signal input circuit  121  connected to the input sockets  115 B and  115 C, an analogue-to-digital converter (ADC)  122  connected to the input circuit  121 , and an RF transceiver (integrated circuit)  123  with antenna  124  connected to the ADC  122 . The input circuit  121  processes the input audio signal, such as selecting amongst the audio sources i.e. channels, and the ADC  122  then converts the audio signal into digital format. The transmitter part of the transceiver  123  subsequently modulates (including compression), amplifies and transmits the digital signal as a wireless RF audio signal, which is equivalent or corresponds to the original input audio signal, for reception by the speaker unit  200 .  
         [0031]     The receiver part of the transceiver  123  serves to receive a wireless RF control signal from the speaker unit  200 , which is equivalent to or represents an IR control signal given by the remote controller  20  for controlling the operation of the audio equipment  10 , as hereinafter described.  
         [0032]     The operating circuit  120  includes a main control unit (MCU)  125  that is connected to the input circuit  121  for controlling the same and also to the transceiver  123  for gathering and processing the aforesaid control signal therefrom and then feeding it to an IR transmitter  126  connected between the MCU  125  and the IR LEDs  113 . The IR transmitter  126  serves to modulate, amplify and transmit the control signal as a wireless IR control signal for reception by the audio equipment  10 .  
         [0033]     The speaker unit  200  also has a generally spherical housing  210  that likewise includes a flat bottom  211  for standing but it is considerably larger than the base housing  110 . On a slanting front  212  of this housing  210 , there are mounted a subwoofer  212 A centrally on the upper half, a pair of main speakers  212 B on opposite left and right sides and a circular LCD display  212 C right below the subwoofer  212 A. A speaker grill  212 D covers the housing front  212 , while exposing the display  212 C. The speaker unit  200  may also operate on AC/DC power, including a DC power jack at the back of its housing  210  for power connection.  
         [0034]     The speaker unit  200  has an IR sensor  213  (the first one of a pair at the same location) right below the housing front  212  for receiving the aforesaid IR control signal from the remote controller  20 . There is a keypad  214  atop the housing  210 , which provides a power on/off key  214 A, a channel selection key  214 B, a pair of volume up (V+) and down (V−) keys  214 C and  214 D, a mute key  214 E, an equalizer key  214 F, a clock key  214 G and a learn key  214 H.  
         [0035]     Provided in the speaker housing  210  is an electronic operating circuit  220  that incorporates, as connected in series, an RF transceiver (integrated circuit)  221  with antenna  222 , a digital-to-analogue converter (DAC)  223  and an audio amplifier  224 . The speaker transceiver  221  is tuned with the base transceiver  123  for its receiver part to receive the wireless digital RF audio signal transmitted by the base transceiver  123 . The DAC  223  then restores the received audio signal into analogue format, and the audio amplifier  224  finally amplifies the analogue audio signal to drive the speakers  212 A and  212 B for sound generation.  
         [0036]     The operating circuit  220  includes a main control unit (MCU)  225  that is connected to and controls the operation of the LCD display  212 C, the transceiver  221  and the audio amplifier  224 . The MCU  225  has built-in clock functions, or is otherwise connected to an external clock chip, for displaying time on the LCD display  212 C with alarm and snooze (optional), etc., essentially in a conventional manner. Such clock functions are executed using the clock key  214 G and the (volume) up and down keys  214 C and  214 D. Another built-in function of the MCU  225  is an audio equalizer (for bass and treble adjustment, etc.) that is activated using the equalizer key  214 F.  
         [0037]     The IR sensor  213  is connected to the MCU  225  for receiving and feeding the aforesaid IR control signal (originated from the remote controller  20 ) to the MCU  225 , which in turn invokes the transceiver  221  to transmit the control signal as a wireless RF control signal for reception by the transceiver  123  of the base unit  100 . In response, the base MCU  125  invokes the IR transmitter  126  and the IR LEDs  113  to reproduce and then transmit the IR control signal to the audio equipment  10  as if the reproduced or reconstructed IR control signal were directly issued by the remote controller  20 . These components together perform a repeat function that repeats and passes on the IR control signal of the remote controller  20  via the wireless digital RF link from the speaker unit  200  to the base unit  100 .  
         [0038]     Certain system control signals are also transmitted via the wireless digital RF link from the speaker unit  200  to the base unit  100 , such as an audio channel select signal issued by the speaker unit  200  using the channel selection key  214 B for controlling the input circuit  121  of the base unit  100 .  
         [0039]     Most of the controls of the audio equipment  10 , such as play/stop for a DVD or CD player or channel select for a TV set, can be passed on using the repeat function. The exceptions are volume control functions i.e. volume up (V+), volume down (V−) and mute, which can be implemented right at the speaker unit  200  given that the unit  200  is fundamentally an active speaker system. This would be necessary for those audio equipment  10  that usually do not have such functions built-in, such as DVD/CD players and pre-amplifiers. For performing the volume control functions, the speaker unit  200  must first learn to comprehend the relevant IR control signals of the remote controller  20 , with the relevant learnt data being stored in a RAM memory  226  connected to the MCU  225 .  
         [0040]     Learning by the speaker unit  200  of the IR remote volume control functions will now be described with reference to  FIG. 8 . To start (Box  300 ), a check is made to determine whether the power on/off button of the selected audio source  10  has been pressed i.e. turned on (Box  301 ). In the affirmative, the memory  226  is clear (Box  302 ), otherwise the IR data length (for V+, V− and mute functions) of each audio source  10  is read from the memory  226  (Box  303 ).  
         [0041]     If the learn key  214 H has been pressed (Box  304 ), learning mode is activated, otherwise the process comes to a stop (Box  311 ). In the learning mode, there is a first period of one minute for the second IR sensor  213  to receive an IR V+ signal from the relevant remote controller  20  (Box  305 ), which upon receipt will be saved in the memory  226  (Box  306 ), otherwise the process will terminate (Box  311 ). The saved data include carry frequency and data length. If the learning mode continues, the process will be repeated for an IR V− signal (Boxes  307  and  308 ) and subsequently for a mute IR signal (Boxes  309  and  310 ).  
         [0042]     The normal operation of the speaker unit  200  performing its IR remote volume control and repeat functions in conjunction with the base unit  100  will now be described with reference to  FIG. 9 . To start (Box  400 ), a check is conducted as to whether an IR control signal is received (Box  401 ) from the remote controller  20  for the selected audio equipment  10 . Upon receiving a V+ signal (Box  402 ) or a V− signal (Box  403 ) that is valid or recognized, the data carried therein is extracted (Box  405 ) and then compared with the V+ data (Box  406 ) or V− data (Box  409 ) previously learnt and saved in the memory  226 . In the affirmative (Box  407 / 410 ), the volume of the speakers  212 A and  212 B will be turned up or down (Box  408 / 411 ) as appropriate, and the process will come to a stop (Box  418 ).  
         [0043]     A similar process is carried out for a mute signal. Upon receiving a valid mute signal (Box  404 ), the data carried therein is compared with the saved mute data (Box  412 ). In the affirmative (Box  413 ), the speakers  212 A and  212 B are muted or unmated (Box  414 ) as appropriate, and the process will terminate (Box  418 ).  
         [0044]     In the case that the IR control signal is neither a V+, a V− nor a mute signal, it will be compressed and converted, etc. (Box  415 ) and then transmitted as a RF control signal for reception by the base unit  100  (Box  416 ). The base unit  100  will subsequently decompress, transform and pass on the control signal as an IR control signal (Box  417 ) for reception by the audio equipment  10 . The IR control signal is thus repeated and afterwards the process terminates (Box  418 ), with the speaker unit  200  awaiting another IR control signal from the remote controller  20 .  
         [0045]     In the case that the learning process for V+, V− and mute signals from the relevant remote controller  20  has not yet been carried out, these signals will simply be passed straight onto the audio source  10  whose speakers will then be adjusted in volume or muted/de-muted.  
         [0046]     Broadly stated, the base and speaker units  100  and  200  are paired for communication with each other in either direction, or bi-directionally and more specifically in a full duplex manner, via radio frequency. That is to say, from the base unit  100  to the speaker unit  200  for transmitting audio signals to avoid speaker wiring, and in the opposite direction for transmitting remote control signals to the source audio equipment conveniently using the same radio frequency link, without consideration of line of sight, for example, as needed for infrared control.  
         [0047]     The MP3 player  10  may have an output for MP3 tags stored inside the MP3 files, which are generally known as ID3 that includes songs&#39; information e.g. names, lyrics and artists (text messages) and pictures (photographic images), etc. To make use of this information, the base unit  100  of the subject invention may include an extra input socket for connection to the ID3 output of the MP3 player  10  for extracting the ID3 data therefrom.  
         [0048]     The ID3 data signal will be handled by the base unit  100  in generally the same manner as the input audio signal, that is to say, processed by the input circuit  121  and then compressed and transmitted by the transceiver  123  as a wireless RF data signal for reception by the speaker unit  200 . Given that the ID3 data is already in digital form, involvement of the ADC  122  may not be necessary. At the speaker unit  200 , the RF ID3 data signal will likewise be received by the transceiver  221  and then processed by the MCU  225  and finally shown on the display  212 C. The MCU  225  should include a decoder program for decoding the ID3 data. The display of ID3 information is somewhat akin to displaying video images.  
         [0049]     Reference is also made to  FIGS. 10 and 11 , which show a second wireless output system embodying the invention for use with an audio/video equipment, such as a TV or DVD player, placed in the lounge for example and an IR (infrared) remote controller for the equipment. The output system is formed by a base unit  100 V and an output, video display unit  200 V for reproducing images and sound originated from the video equipment. This output system is, in principle and operation, generally the same as the previous speaker system except that it now processes video (with audio) signals instead of only audio signals, with equivalent components designated by the same reference numerals suffixed by a letter “V”.  
         [0050]     Most of the other figures, i.e. FIGS.  1  to  9  excluding  FIGS. 4 and 7 , as well as the relevant description on construction and operation are equally applicable to the second output system, with the word and features/content relating to “audio” being replaced by “video” whenever necessary or appropriate.  
         [0051]     Both the base and the video display units  100 V and  200 V are used like their audio counterparts as previously described. Their basic constructions may also be the same as is apparent by comparing  FIGS. 10 and 11  to earlier  FIGS. 4 and 7 , with the exception that their operating circuits  120 V and  220 V include respective DSP processors (digital signal processors) with video encoder/decoder  125 V and  225 V in place of the previous MCUs  125  and  225 .  
         [0052]     For displaying video, the display unit  200 V may be made bigger to accommodate a larger LCD display  212 CV that is equivalent to the earlier display  212 C but upgraded to a suitably higher resolution. Alternatively, or as an addition, instead of having a built-in video display the display unit  200 V may be designed for connection to an external video display screen or monitor, in which case the display unit  200 V may keep the shape (spherical) or size as its audio counterpart.  
         [0053]     The display unit  200 V likewise includes the aforesaid leaning function so as to learn certain remote control functions that can be implemented locally and to effect the same in situ, i.e. volume adjustment and mute, as described in relation to the speaker unit  200 . In the present case,  4 there are more such local functions that can be handled by the display unit  200 V, namely picture control functions i.e. brightness, contrast and colour, etc.  
         [0054]     For use with a MP3 player, this output system may be made such that its base unit  100 V can extract the ID3 data and its display unit  200 V can display the same while outputting the songs.  
         [0055]     It is envisaged that the remote volume control function performed at the output unit  200 / 220 V may be relinquished and included in the general remote repeat function for simplicity in circuit design and operation.  
         [0056]     The use of radio frequency for signal transmission and reception between the base and output units  100 / 100 V and  200 / 200 V is advantageous as this medium of transmission is non-directional, though it is not essential in the broadest sense as technologies advance, that is to say any other suitable types of wireless link may be employed instead.  
         [0057]     The phrase “audio/video” used herein represents “audio and/or video” so that the phrase encompasses, inter alia, an audio element (feature or implication) with or without a video element.  
         [0058]     The invention has been given by way of example only, and various other modifications of and/or alterations to the described embodiments may be made by persons skilled in the art without departing from the scope of the invention as specified in the appended claims.