Abstract:
Delivery of programming from a content provider to one or more hand held devices is effected via a set-top box (STB). The STB receives a transport stream, recognizes and de-multiplexes out a co-cast content association table containing a list of all available co-cast programming, and broadcasts table to the one or more hand held devices. Each hand held device displays the list and a program therefrom is selected. The selection is transmitted to the STB, which de-multiplexes out the selection from the delivered programming, and re-multiplexes the requested co-cast programming into a transport stream for broadcast to the requesting hand held device.

Description:
CLAIM OF PRIORITY 
     The present invention claims priority from regular application Ser. No. 10/839,783 filed on Apr. 27, 2004 and incorporates said application by reference as if fully set forth herein. 
     FIELD OF THE INVENTION 
     The invention herein discloses an exemplary method and apparatus to transmit content to a viewer&#39;s wireless hand held device as an alternative or complement to TV viewing, using a digital satellite, cable or terrestrial set-top-box, an interne enabled set-top box, or an analog broadcast with digital extraction and a wireless reception device. 
     BACKGROUND 
     Referring to  FIG. 1 , currently the vast majority of digital television program providers, whether cable, satellite, or terrestrial transmissions, transmit digital content from transmitting station  110  to satellite  125  via channel  120 . Satellite  125  retransmits the digital content digital to one or more satellite dishes  130 . Satellite dish  130  may be a large satellite dish owned and operated by a local cable company, or it may a personal satellite dish serving one home. The satellite dish then transmits the content, usually via bi-directional coaxial cable  140 , to each cable subscriber via set-top-box (STB)  150 . STB  150  demodulates, or extracts information from, the digital signal in the form of packets, or fragments, from the carrier, and performs different signal processing techniques, i.e. error correcting, demultiplexing, descrambling and decoding to decode the digital programs in the form of video, audio or data, and converts such digital data to analog form to playback such decoded signals on a TV set as shown in  FIG. 1 . Such connection between the playback device (TV) and the STB are done with cables and use the analog signals produced by the STB. 
     Today, the relationship between a traditional set top box and a hand held device is limited to hand held devices, and more specifically, only personal video devices, downloading, for later viewing, the content which is currently being viewed from the set top box. 
     The instant invention represents an improvement over wide area hand held receivers utilizing the DVB-H or DMB standards. DVB-H, or Digital Video Broadcasting, refers to the hand held version of DVB-T or Digital Video Broadcasting-Terrestrial, which is a system for the Terrestrial broadcast of signals destined for playback on hand held devices. DMB, or Digital Multimedia Broadcast, is a digital radio transmission system for sending multimedia (radio, TV, and datacasting) to mobile devices such as mobile phones. 
     The current system has proven inadequate for most wireless applications, and in particular, to mobile wireless devices. Mobile wireless devices generally fall under the category of hand held devices, and include cell phones, personal digital assistants (pda&#39;s), etc. These devices share the common characteristic of being small, easily transported, and useable under most circumstances. Unlike portable computers and other larger mobile devices, hand-held devices do not require a surface to be placed on, nor do they usually have fixed or removable, mass storage devices such as hard drives, magneto-optical drives, or optical drives. The storage is generally limited to on-board memory or small removable memory such as flash media cards. 
     The difficulty with transmitting content, and in particular, rich media, defined as content exhibiting one or more characteristics of user interaction, advanced animation, and or audio/video is that it requires large bandwidth and bi-directional communication for error correction. Small, wireless devices generally do not have the available bandwidth or sufficient power to reach the content distributor to request that corrupted packets of information be resent. Also, current systems do not provide a practical means for reasonable interaction between a hand held device and a television program. 
     In the present invention, digital data encoded to be received by one or more handheld devices for playback is inserted into the transport stream by the content provider and is transmitted via satellite, cable or terrestrial television digital channels to a STB and wirelessly re-transmitted to a handheld receiver for decoding and playback using modern forms of wireless transmission such as Bluetooth, infrared, fast-infrared (FIR) or 802.11x. Such data can be digitally compressed audio, video, program information, hypertext links, game files, etc. 
     In the present invention, the set-top box obtains instructions from the wireless device regarding what content to transmit to it. The STB uses the index data supplied by the broadcaster embedded in the data stream to determine what content to transmit. 
     BRIEF SUMMARY OF THE INVENTION 
     The instant invention relates to an exemplary method and apparatus for delivering rich media to wireless hand held devices which do not have sufficient power or bandwidth to obtain the content directly from a content provider. The instant invention solves this problem by sending the rich media to an STB which re-transmits the rich media to the wireless hand held device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates how the average end-user receives digital television programming. 
         FIG. 1   a  illustrates a high level schematic diagram of how digital content is processed for transmission to an end-user. 
         FIG. 1   b , is an example of a lower level schematic diagram of the creation of a Transport Stream from packetized elementary streams. 
         FIG. 1   c , illustrates a simplified, sample, MPEG compliant packet. 
         FIG. 2  illustrates an example of how co-cast programming is multiplexed with regular digital programming. 
         FIG. 3  illustrates multiple embodiments of the invention 
         FIG. 3   a  illustrates one embodiment of the invention where the STB demultiplexes the requested co-cast programming from the Transport Stream for transmission. 
         FIG. 3   b  illustrates one embodiment of the invention where the STB demultiplexes all co-cast programming from the Transport Stream for transmission. 
         FIG. 3   c  illustrates one embodiment of the invention where the STB re-transmits the entire Transport Stream. 
         FIG. 4  is a flow diagram on one embodiment of the invention 
         FIG. 5  illustrates the control logic 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The invention herein disclosed provides an exemplary solution to the problem of delivering rich media to wireless devices, and in particular to small hand held wireless devices for the purpose of interactive television, more recently known as participation television. This is accomplished by wirelessly enabling STB devices so that they can wirelessly transmit rich media to one or more hand held wireless devices for final storage and playback while simultaneously transmitting broadcast quality content to a television set. The rich media transmitted to the wireless hand held device is known as Co-Cast information. For purposes of this disclosure, co-cast content refers to content which is inserted into the transport stream and intended for playback on devices other than a television set, e.g. wireless handheld device, laptop, personal, computer, pda, or mobile phone. Generally, co-cast information bears a logical relationship to the content that is being displayed on the television set, although that is not required. Alternatively, co-cast information may be wholly independent of the channel being displayed on the television set. Such co-cast information is defined here as the globally available co-cast content. The broadcaster who inserted the co-cast content into the transport stream may also place restrictions on its use. Some restriction may include, a limited period of time for accessibility, another example may include a geographic limitations, etc. An example of a limited time usage would be co-cast programming which directs the viewer to a voting website. Some of the more popular wireless protocols include infra-red, fast infra-red, and 802.11x. 
     In another embodiment of the invention, the STB has multiple output designed for wired connectivity, each output being capable of transmitting different content. 
     Referring to  FIG. 1   a ,  FIG. 1   a  illustrates a high level schematic diagram of how digital content is processed for transmission to an end-user. Rich media, e.g. Content  160   a , a movie, Content  160   b  a news cast, Content  160   c , a Sports Program, and Content  160   d , Data Tables, is first encoded as elementary streams. An elementary stream is the output of a video or audio encoder, and may only contain one type of data, e.g. audio, video, etc. In the MPEG communications protocol, elementary streams are packetized, i.e. broken down into smaller pieces, i.e. packets. In a traditional MPEG system, each transport packet is 188 bytes in length and contains a header, and a payload. The header contains such index information as time index, program identifier, and payload type (whether audio, video, program information, etc.). In addition to being packetized, the various elementary streams of each program are combined or multiplexed ( 161 ) into Packetized Elementary Streams  162   a ,  162   b ,  162   c , and  162   d . Each Packetized Elementary Stream contains the combined data (audio, video, date, etc.) of a single program, i.e. Content  160   a ,  160   b ,  160   c , or  160   d . When the packets reach the set top box, the set top box demultiplexes, i.e. recombines the packets into single programs, based upon the header information and is able to present the original content to the display unit. The demultiplexer also ensures the desired packets are displayed in the correct chronological order. 
     Each Packetized Elementary Stream is then further multiplexed ( 163 ) into single Transport Stream  164  carrying packets from each Packetized Elementary Stream  162   a  et al. A transport stream contains packetized data from multiple programs. Transport Stream  164  is broadcast to the consumer and received by the consumer&#39;s set top box, STB  165 , which demultiplexes Transport Stream  164 . 
     Referring to  FIG. 1   b ,  FIG. 1   b , is an example of a lower level schematic diagram of the creation of a Transport Stream from packetized elementary streams. Elementary Stream  170  represents Program  1 . Elementary Stream  175  represents a different program, i.e. Program  2 . Multiplexer  180  multiplexes or combines the three elementary streams that compose the audio, video, and data of Program  1  into Single Packetized Elementary stream  180   a . Similarly, multiplex  181 , multiplexes or combines the three elementary stream that compose the audio, video, and data, of Program  2  into single Packetized Elemental Stream  181   a.    
     Multiplexer  190  combines both Packetized Elementary Streams  180   a  and  181   a  into Single Transport Stream  195  which is what is actually broadcast or transmitted to the end user&#39;s STB. 
     Referring to  FIG. 1   c ,  FIG. 1   c , illustrates a simplified, sample, MPEG compliant packet. Packet  198  is composed of 2 sections, Header  196  and Payload  197 . 
     The content provider, i.e. Cable Company, Satellite Company, network, studio, etc. may elect to insert Co-Cast information into the transport stream. Like any other information in the transport stream, co-cast information would be packetized with a header and payload. The header would include the traditional information associated with an MPEG header. However, in addition, the header of co-cast information would include an identifier that the packet is a co-cast packet. The payload of the co-cast packet is similar to the payload of a traditional MPEG packet except that it may also include hypertext links, which is not traditionally seen in MPEG packets. 
     In a regular MPEG based digital television system, the set top box knows the channel line-up by reading the Payload of the Program Association Table. Said Program Association Table traditionally has a program identifier set to ZERO. In the instant invention, available co-cast content is determined by the STB by reading the payload of the Co-Cast Content Association Table, which is analogous to the Program Association Table. The Co-Cast Content Association Table is identified by the Program Identifier in the header. 
     Referring to  FIG. 2 ,  FIG. 2  illustrates an example of how co-cast programming is multiplexed with regular digital programming. Program  1  or Packetized Elementary Stream  250 , Co-Cast  1  or Packetized Elementary Stream  260 , and Program  2  or Packetized Elementary Stream  270  are transmitted to Multiplexer  280  which combines the three packetized elementary streams into Single Transport Stream  290 . 
     Referring to  FIG. 3 ,  FIG. 3  illustrates multiple embodiments of the invention; STB  320  receives the content, in packetized form, via coaxial cable  310 . STB  320  is wireless enabled to transmit and receive information via wireless communications such as infra-red, fast-infrared (FIR), Bluetooth, or 802.11x. STB  320  is also configured with two or more demultiplexers  330 . Multiple demultiplexers allow different receiving devices to receive different content at the same time. One channel is transmitted via transmission means  340  to television set  350 . One or more channels are transmitted wireless via wireless transmitter  360  over one or more bi-directional wireless channels  370 , to one or more wireless devices  390 . Each wireless device may receive different content up to the number of demultiplexers available (minus the demultiplexer being used by the television set). Such content can be streamed for real time decoding by the handheld device, or downloaded to devices with enough storage capabilities for later decoding or playback. Bi-directional channel  370  allows the hand held devices to request retransmission of corrupted packets from the STB  320 , thus allowing rich media to be transmitted. Bi-direction channels  370  may represent diverse technologies, to wit, the STB  320  may transmit using one wireless technology, and receive information such as data or commands via another wireless technology. In addition, the invention can communicate via WiMax  381  or Wi-Fi router  382 . 
     Referring to  FIG. 3   a ,  FIG. 3   a  illustrates one embodiment of the STB, transmitting co-cast content to the handheld device. The STB receives Transport Stream  375 , performs the demultiplexing and decoding on the incoming packet stream and broadcasts Transport Stream  375   a  which is composed solely of co-cast packets that were requested by each handheld device. 
     Referring to  FIG. 3   b ,  FIG. 3   b  illustrates a second embodiment of the STB transmitting co-cast content to the handheld device. STB  320  acts as a router, and broadcasts all packets from Transport Stream  380  which are identified as co-cast packets into Transport Stream  380   a . Each hand held device performs its own demultiplexing and decoding of the packetized stream. This method permits the user view all co-cast content, whether associated with a particular channel or not. 
     Referring to  FIG. 3   c ,  FIG. 3   c  illustrates yet another embodiment of the STB transmitting co-cast content to the handheld devices. In this embodiment, the STB  320  merely rebroadcasts Transport Stream  385  as received. Each hand held device would be responsible for processing the entire packetized stream and performing demultiplexing and decoding as necessary. This method is suboptimal in that it requires each handheld device to have a demultiplexer as powerful as the one in STB  320 , which would substantially increase the cost of each handheld device 
     Referring again to  FIG. 3 ,  FIG. 3  further refers to another embodiment of the invention. STB  320  received the content via coaxial cable  310 . STB  320  extracts Co-cast identification information from the requested packets. This co-cast identification, information includes, but is not limited to a list of titles and locations of the co-cast content. The location may be the internet, another network, the packetized content being received by the coaxial cable  310 , cached on STB  320 , or from a mass storage device attached to STB  320 . STB  320  is wireless enabled. Examples of the extracted co-cast index information include, Internet URL&#39;s, DVD title, chapter, and time index information, Hard drive file location, etc. The co-cast index information is transmitted to one or more wireless devices  390  via wireless transmitter  360 . Each wireless device  390  receives the identical list of co-cast content. 
     Wireless device  390  is wirelessly connected to both STB  320 , the internet via Router  382 , or Tower  381 , where Tower  381  can be a cell tower or a WiMax tower. The user selects the desired content to be co-cast and hand held device  390  uses the co-cast index information to obtain the desired content. 
     Referring yet again to  FIG. 3 , in another embodiment of the invention, STB  320  is connected to the public internet  397  via connection means  375 . This permits STB  320  to obtain and transmit information from the internet as well. 
     Referring yet again to  FIG. 3 , in another embodiment of the invention, STB  320  receives content from a mass storage device such as a hard drive, an optical drive, or a solid state memory device. 
     Referring to  FIG. 4 ,  FIG. 4  is a flow diagram of one embodiment of the invention. At step  405 , the STB broadcasts the list of available content by reading the payload of the Co-cast Content Association Table. At step  410  a first hand held device requests co-cast content associated with the currently viewed television channel from the STB. At step  420  a second hand held device simultaneously requests globally available co-cast content from the STB. At step  445  one or more demultiplexers separate the requested co-cast information from the packetized stream and broadcasts one or more transport streams. At step  450 , the STB transmits the co-cast information to the wireless handheld devices. At step  460  each hand held device receives the transmitted data, ignore the packets not intended for it, and reconstructs the content. 
     Referring to  FIG. 5 ,  FIG. 5  illustrates a block diagram of the control logic of the STB. At step  510 , the STB send the input signal through a de-multiplexer and decryption device. At step  520 , the STB transcodes the signal into the format for the wireless device. At step  530 , the signal is re-packetized for streaming or downloading. At step  540 , the signal passes through the wireless interface. At step  550 , the STB processes the return channel commands. At step  560  the system controller will instruct the transport demultiplexer  510  to extract the co-cast channel requested by the hand held device.