Abstract:
A system for re-broadcasting a received media stream to multiple media players includes an input port for receiving the media stream, a processor for decoding the media stream into a format suitable for rebroadcast, and an output port for re-broadcasting the media stream to a plurality of media players.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a non-provisional of and claims priority to pending U.S. Provisional Patent Application Ser. No. 61/625,431, filed Apr. 17, 2012, the disclosure of which is hereby incorporated by reference in their entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    Embodiments of the present invention relate generally to digital audio processing and, in particular, to broadcasting audio over a wired or wireless network connection. 
       BACKGROUND 
       [0003]    Bluetooth is a very popular and frequently used wireless protocol for sending digital signals between two devices. Many smartphones, laptops, tablets, and other such consumer electronic devices, for example, are capable of sending and receiving Bluetooth signals. Users of said devices may use Bluetooth to transmit audio and/or video media from their device to a media player (such as, for example, a Bluetooth-enabled loudspeaker or pair of headphones). One of the limitations of Bluetooth, however, is that it is incapable of transmitting to multiple receivers, so that an audio stream cannot be (for example) transmitted to a first loudspeaker in a first room and to a second loudspeaker in a second room. Other methods of broadcasting an audio and/or video stream from a consumer device (e.g., WiFi) may also be unsuitable because the high-latency nature of the broadcasting leads to unsynchronized audio and video, and also because broadcasting WiFi to multiple recipients may require the installation of additional software on the device (if it is even possible at all). A need therefore exists for a way to quickly and efficiently stream audio and/or visual data via a Bluetooth link to multiple recipients. 
       SUMMARY 
       [0004]    In general, various aspects of the systems and methods described herein receive a Bluetooth signal bearing audio and/or video data, convert the received data into an RF output, and broadcast the RF output to one or more devices for playback of the audio and/or video data, 
         [0005]    These and other objects, along with advantages and features of the present invention herein disclosed, will become more apparent through reference to the following description, the accompanying drawings, and the claims. Furthermore, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and can exist in various combinations and permutations. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    In the drawings, like reference characters generally refer to the same parts throughout the different views. In the following description, various embodiments of the present invention are described with reference to the following drawings, in which: 
           [0007]      FIG. 1  illustrates a system for broadcasting media from a Bluetooth stream to multiple devices in accordance with an embodiment of the invention; 
           [0008]      FIG. 2  illustrates a transceiver for broadcasting a received Bluetooth stream to multiple devices in accordance with an embodiment of the invention; 
           [0009]      FIG. 3  illustrates an implementation of a receiver/transmitter in accordance with an embodiment of the invention; and 
           [0010]      FIG. 4  illustrates an audiovisual system in accordance with an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]      FIG. 1  illustrates a receiver/transmitter  100  that is configured to communicate via a Bluetooth link  102  with a wireless media source  104  (e.g., a smartphone, laptop, tablet, or other such device). The receiver/transmitter  100  may be a standalone device, such as a “wall wart,” desktop box, or other such device, or its functionality may be combined with another device or devices. The receiver/transmitter  100  may be included, for example, within a combination lighting fixture/sound system (such as the MUSICLITE offered by ARTISON and SYLVANIA), a soundbar, or some other speaker/electronics package. The wireless link  102  is described herein as a Bluetooth link, but the current invention is not limited to any particular protocol of wireless data transmission, and the link  102  may include any wireless data protocol as known in the art. The receiver/transmitter  100  receives audio and/or visual data over the wireless link  102  in the form of a digital or analog signal, processes (e.g., decodes) the data with minimal latency overhead, and re-transmits the audio and/or visual data (via another link or links  108 ) to one or more wireless media players  106  (e.g., one, two, three, four, or more media players  106 ) via a protocol that supports the broadcasting of data to multiple recipients. In various embodiments, the link  108  is an RF link or an infrared link. The media player  106  may be a loudspeaker, for example, that includes an RF receiver compatible with the link  108 . The link  108  may vary for each media player  106  to enable (for example) differentiation between left, right, center, and rear speakers; in another embodiment the receiver/transmitter broadcasts a single, combined signal over the link  108 , and each media layer  106  is configured to play back a different portion of the combined signal. 
         [0012]    In various embodiments, the wireless re-broadcast link  108  operates using a frequency of 2.4 GHz, 5.8 GHz, 900 MHz, but any suitable frequency is within the scope of the current invention. If the same broadcast frequency is used for both the Bluetooth link  102  and the RF link  108 , antenna replacement and/or hopping (i.e., automatic channel switching) may be used to prevent or reduced interference between the links  102 ,  108 . In one embodiment, opposing-polarity antennas are used to minimize interference between the Bluetooth  102  and RF  108  links. 
         [0013]    Alternatively or in addition, the receiver/transmitter  100  may receive a wired audio and/or video stream  110  from a wired media source  112  (e.g., a television, portable music player, or other such wired device). The wired media source  112  may also be a wireless device (e.g., a smartphone) configured as a wired device (by, e.g., connecting to the receiver/transmitter  100  via an audio cable). The wired link  110  may be any type of cable or protocol, include audio cables, HDMI cables, Ethernet cables, or any other type of wired connection; the current invention is not limited to any particular type of cable. 
         [0014]    Either media source (the wireless  104  or the wired  112 ) may itself display or play back media content while also sending the same or different content via the links  102 ,  110  to the wireless media player  106  via the receiver/transmitter  100 . For example, the wired media source  112  may be a television displaying video media locally (i.e., at the location of the media source  112 ) while sending audio data related to the video media to the receiver/transmitter  100 . In another example, the wireless media source  104  may play music while sending a copy of the music to the receiver/transmitter  100 . In each case, the receiver/transmitter  100  receives the incoming data, decodes/processes it, and re-broadcasts it via the link  108  with a low enough latency to be imperceptible, or nearly imperceptible, to human senses. For example, the delay between viewing video data playing back on the wired media source  112  and hearing its associated audio data via the wireless media player  108  (i.e., so-called “lip sync” delay) may be less than 100 ms, 50 ms, or 20 ms. Similarly, a delay between audio broadcast by one or more of the media sources  104 ,  112  and audio broadcast by the wireless media player  108  may be less than 100 ms, 50 ms, or 20 ms. 
         [0015]    Control of the receiver/transmitter  100  (e.g., power on/off, input selection, output selection, volume level, digital-signal processing effects, or any other such control or feature) may come from one or more sources. In one embodiment, the wireless  104  or wired  112  media source is configured to run a software, firmware, and/or hardware application that may send and/or receive control signals over the links  102 ,  110 . For example, control signals may be multiplexed with audio and/or video data flowing over the Bluetooth link  102 ; in another embodiment, control signals may be similarly multiplexed over the wired link  110  or may be sent over a dedicated signal wire included in the link  110 . The control application may be a smartphone/tablet application downloaded using a commercially available market interface, for example, or a computer application downloaded from the Internet or a local network. In another embodiment, the receiver/transmitter  100  includes a web server, and the media sources  104 ,  112  may control the receiver/transmitter using a web browser. Alternatively or in addition, a remote control  114  may be used to communicate with the receiver/transmitter  100  via (for example) an infrared link  116 . 
         [0016]    The receiver/transmitter  100  may broadcast an output signal to different kinds of devices. As discussed above, one device may be the wireless media player  106 . The receiver/transmitter  100  may alternatively or in addition send an output signal to a wired media player  118 , which may be (for example) a wired loudspeaker. In one embodiment, receiver/transmitter  100  sends an output signal  120  to an audio amplifier/receiver/relay  122 , which relays the output signal to an additional wired media player or players  124 . In this embodiment, the output signal  120  (which may be a wired or wireless link) may be a bundle or group of several audio signals (e.g., five-channel surround-sound signals). The receiver  122  receives the bundled signals and drives the wired media players  124  appropriately. 
         [0017]    In one embodiment, the receiver/transmitter  100  communicates with an additional receiver/transmitter  100 ′ via a peer-to-peer link  126 . The additional receiver/transmitter  100 ′ may be positioned remotely to the first receiver/transmitter  100  (in, e.g., another room of a house). The first receiver/transmitter  100  may send audio and/or visual data, as well as control signals, over the link  126  to the additional receiver/transmitter  100 ′; the additional receiver/transmitter  100 ′ may thereafter broadcast an RF signal to additional media players not otherwise accessible to the first receiver/transmitter  100 . The two receiver/transmitters  100 ,  100 ′ may coordinate the playback of shared media to account for any delay incurred by the link  126  (by, for example, delaying playback from the first receiver/transmitter  100  by a time equal to the latency of the link  126 ). Any number of additional receiver/transmitters may be added (in parallel with the additional receiver/transmitter  100 ′ or chained in series from the additional receiver/transmitter  100 ′). 
         [0018]    The receiver/transmitter  100  may authenticate the wireless media source  104  before fully establishing the wireless link  102 . For example, a user of the wireless media source  104  may press a button on the receiver/transmitter  100  to put its Bluetooth interface in “search mode” and/or confirm establishment of the link  102  by interacting with a menu, button, or dialog box on the wireless media source  104 . In one embodiment, the link  102  may be established by physical contact (or close proximity) between the wireless media source  104  and the receiver/transmitter  100  (via, for example, an RFID chip in the wireless media source  104  and an RFID scanner in the receiver/transmitter  100 ). Such a system of authentication may be used, for example, in an environment having multiple receiver/transmitters  100  controlling separate audio/visual systems; a user of the wireless media source  104  may specify one particular receiver/transmitter  100  for interaction therewith. The unselected receiver/transmitters  100  thereafter ignore commands and media sent from the wireless media source  100 . Furthermore, other users having Bluetooth-enabled devices are prevented from interacting with the selected receiver/transmitter  100  (either unintentionally or maliciously). 
         [0019]    In one embodiment, a hotel, motel, bed-and-breakfast, or other similar provider of guest rooms provides a receiver/transmitter  100  in one or more of said rooms. A guest may use the receiver/transmitter  100  to play back audio data from a TV or music player also installed in the room via (for example) a provided remote control. The guest may also connect to the receiver/transmitter  100  using his or her own Bluetooth-enabled smartphone, tablet, laptop, or other such device. The receiver/transmitter  100  may broadcast an identification string to assist the guest in selecting the receiver/transmitter  100  disposed in the current room and not (for example) another receiver/transmitter  100  in an adjacent room. The guest may authenticate access with the receiver/transmitter  100  as described above. Once authenticated, the guest may use his or her personal device as a remote control to play back the provided media and/or stream personal media from his or her personal device. The receiver/transmitter  100  may log each successful and/or unsuccessful authentication attempt; the guest-room provider may charge the guest (either before or after authentication is completed) for access thereto. Any wireless media players in the room (e.g., the media player or players  106 ) may be configured with RF receivers that communicate only with the receiver/transmitter  100  disposed in the room and not (for example) a receiver/transmitter  100  in an adjacent room. 
         [0020]      FIG. 2  illustrates one embodiment  200  of the receiver/transmitter  100 . A low-latency processor  202  is used to decode/process/modify/etc. incoming streams of audio data and format them for re-broadcast in a different format. The processor  202  may be any digital, analog, or mixed-signal processor known in the art, such as a microprocessor, microcontroller, ASIC, digital-signal processor, or other similar devices. The system may also include volatile and/or non-volatile storage  204 , such as RAM, SRAM, flash memory, firmware, a disk-based or solid-state hard drive, or any other medium. Input signals are received from an infrared receiver  206 , a Bluetooth receiver  208 , and/or a wired receiver  210 . Each receiver  206 ,  208 ,  210  may include receiver electronics, antennas, ESD and surge protection circuitry, and/or other circuitry necessary to function, as one of skill in the art will understand. After processing by the processor  202 , the received data (e.g., audio data) is re-broadcast using one or more output interfaces, such as an RF output driver  212 , a wired output driver  214 , and/or a peer-to-peer output driver  216  (which may broadcast either a wired or wireless output signal). The system  200  may also include local controls  218  for local access, such as a power switch, a reset button, and/or a Bluetooth “pairing” button or proximity interface. The system  200  may also be accessed via any of the input ports  206 ,  208 ,  210  for diagnostic, control, or debugging purposes. 
         [0021]      FIG. 3  illustrates an illustrative embodiment  300  of the receiver/transmitter. A main section  302  houses the electronics of the unit (e.g., the microprocessor, input ports, and output ports) and an antenna  304  is used to send and/or receive signals. The main section  302  may have an AC adapter (not shown) for plugging into a standard power outlet. 
         [0022]      FIG. 4  illustrates an illustrative system  400  that uses the receiver/transmitter  300 . A smartphone  402  provides a stream of audio data that may be sent to a pair of headphones  404 , a loudspeaker  406 , or to the receiver/transmitter  300 . The receiver/transmitter  300  may re-broadcast the audio data to one or more media players, such as a sound bar  408 , a subwoofer  410 , and combination light/media-playing devices  412 . A TV  414  may provide an additional stream of audio data to the receiver/transmitter  300 , which may select between and/or mix the two incoming streams of audio data. 
         [0023]    It should also be noted that embodiments of the present invention may be provided as one or more computer-readable programs embodied on or in one or more articles of manufacture. The article of manufacture may be any suitable hardware apparatus, such as, for example, a floppy disk, a hard disk, a CD ROM, a CD-RW, a CD-R, a DVD ROM, a DVD-RW, a DVD-R, a flash memory card, a PROM, a RAM, a ROM, or a magnetic tape. In general, the computer-readable programs may be implemented in any programming language. Some examples of languages that may be used include C, C++, or JAVA. The software programs may be further translated into machine language or virtual machine instructions and stored in a program file in that form. The program file may then be stored on or in one or more of the articles of manufacture. 
         [0024]    Certain embodiments of the present invention were described above. It is, however, expressly noted that the present invention is not limited to those embodiments, but rather the intention is that additions and modifications to what was expressly described herein are also included within the scope of the invention. Moreover, it is to be understood that the features of the various embodiments described herein were not mutually exclusive and can exist in various combinations and permutations, even if such combinations or permutations were not made express herein, without departing from the spirit and scope of the invention. In fact, variations, modifications, and other implementations of what was described herein will occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention. As such, the invention is not to be defined only by the preceding illustrative description.