Abstract:
A home content distribution solution that provides distribution capabilities between a Home Media Server (HMS) and remote units, such as a thin Client stand-alone box or an existing legacy digital set-top box (STB). The invention permits combined video and data home networking while leveraging the numbers of already deployed digital set-top boxes. Embodiments of the system and methods are employed to distribute content to a set-top box connected to a home distribution network, which preferably includes a home media server connected to the home distribution network; a reflector, and; an entry point device having entry terminal for connection to an external cable network, a first output terminal for connection to the home distribution network and a second output terminal for connection to the reflector. Content is typically obtained from both the home media server and the cable network and distributed over the home distribution network. The content obtained from both the home media server and the cable network is displayable by an analog television connected to the set-top box.

Description:
RELATED APPLICATIONS  
       [0001]    This application claims the benefit of and priority to the co-pending U.S. Provisional Application, Serial No. 60/408,307, filed Sep. 5, 2002, entitled “Combination of a Home Network Unit and a Support for Legacy Digital STB Devices” the entire contents of which are incorporated herein by reference.  
         [0002]    This application further claims the benefit of and priority to the co-pending U.S. Non-Provisional application Ser. No. 10/234,358 filed Sep. 4, 2002 entitled “Home Network System and Method,” which claims the benefit of and priority to U.S. Non-provisional application Ser. No. 09/943,424 filed Aug. 30, 2001, which claims the benefit of the filing date of co-pending U.S. Provisional Application, Serial No. 60/229,263, filed Aug. 30, 2000, entitled “Home Network Method And Apparatus,” Provisional Application, Serial No. 60/230,110, filed Sep. 5, 2000, entitled “Home Network Method And Apparatus,” Provisional Application, Serial No. 60/275,060, filed Mar. 12, 2001, Provisional Application, Serial No. 60/291,130, filed May 15, 2001, and Provisional Application, Serial No. 60/297,304, filed Jun. 11, 2001, the entirety of which provisional and non-provisional applications are incorporated by reference herein. 
     
    
     
       FIELD OF THE INVENTION  
         [0003]    The invention relates generally to a home network content distribution system and more specifically to a home network content distribution system that provides content to legacy digital set-top boxes.  
         BACKGROUND OF THE INVENTION  
         [0004]    As the demand for the ability to distribute media content from a home media server into various rooms of the home increases, those who make the hardware for such content distribution are faced with the following reality. First, there is a significant home distribution network infrastructure, in the form of coaxial cables, already in place in a large number of residences. Second a large number of residences already possess a digital set-top box to which is connected an analog television.  
           [0005]    Hardware manufacturers have developed thin-client hardware that is placed into each room to which home media server content is to be distributed. This hardware converts the signals from the home media server into signals understandable by television receivers. Such thin-client hardware communicates with the home media server by way of the existing home distribution network coaxial wire infrastructure. Although such thin client hardware does provide a means of distributing content to each room with thin-client hardware using one portion of the installed base (i.e. the coaxial wires), such a system generally does not provide any mechanism to permit existing or legacy digital set-top boxes to receive such content from the home media server without this thin client hardware.  
           [0006]    The present invention addresses the need for allowing legacy set-top boxes to receive and play home media server content without requiring additional thin-client hardware and while permitting standard cable television signals to enter and be distributed by the home distribution network.  
         SUMMARY OF THE INVENTION  
         [0007]    The present invention relates to a home content distribution solution that provides distribution capabilities between a Home Media Server (HMS) and remote units, such as a thin Client stand-alone box or an existing legacy digital set-top box (STB). The invention permits combined video and data home networking while leveraging the numbers of already deployed digital set-top boxes. Only in circumstances in which there are no legacy digital set top boxes are installed are new thin client boxes required.  
           [0008]    In one embodiment a system for distributing content to a set-top box connected to a home distribution network includes a home media server connected to the home distribution network; a reflector, and; an entry point device having entry terminal for connection to an external cable network, a first output terminal for connection to the home distribution network and a second output terminal for connection to the reflector. In this embodiment the content is obtained from both the home media server and the cable network and distributed over the home distribution network. The content obtained from both the home media server and the cable network is displayable by an analog television connected to the set-top box.  
           [0009]    In another embodiment, the home media server communicates commands with the set-top box over the home distribution network using a command channel. In yet another embodiment, the command channel uses the reverse data band.  
           [0010]    In still another embodiment, the content from the home media server is carried over the home distribution network within a first predetermined frequency band; the content from said cable network is carried over the home distribution network within a second predetermined frequency band; and the home media server is controlled by a home media server control signal from said set-top box, that is carried over said home distribution network within a third predetermined frequency band.  
           [0011]    In another embodiment, the entry point device includes a low pass filter connected to the entry terminal and a directional coupler connected between the low pass filter and the first and second output terminals. In one embodiment the reflector is an active reflector. The reflector includes a reflector input terminal, a reflector diplexer, a reflector RF section and a SAW filter. The reflector diplexer has a first diplexer output and a first diplexer input and a second diplexer input connected to the reflector input terminal. The reflector RF section has a first RF input connected to said first diplexer output, a second RF input, a first RF output connected to said first diplexer input, and a second RF output. The SAW filter has a SAW input connected to said second RF section output and a SAW output connected to said second RF section input. In this embodiment the active reflector receives signals in a first band and reflects them in a second band having a lower frequency than said first band.  
           [0012]    In still yet another embodiment, the home media server includes an HMS diplexer, an HMS RF section and an HMS signal processor. The HMS diplexer has a first HMS diplexer input, a first HMS diplexer output and a second HMS diplexer input connected to the home media server input. The HMS RF section has a first HMS RF section input connected to the HMS diplexer output, two second HMS RF section inputs, a first HMS RF section output connected to the HMS diplexer input, and a second HMS RF section output. The HMS signal processor has a first HMS signal processor input connected to the second HMS RF section output. The HMS signal processor also has two HMS signal processor outputs, one of each is connected to a respective one of the two second HMS RF section inputs.  
           [0013]    The invention also relates to a method for distributing content from an external cable network and a home media server to a set-top box connected to a home distribution network. The method includes the steps of passing content carried by a first predetermined frequency band from the cable network to the set-top box over the home distribution network; passing control signals carried by a second predetermined frequency band from the set-top box to the home media server over the distribution network; and passing content carried by a third predetermined frequency band from the home media server to the set-top box over the home distribution network. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0014]    The aspects of the invention presented above and many of the accompanying advantages of the present invention will become better understood by referring to the included drawings, which show a system according to the preferred embodiment of the invention and in which:  
         [0015]    [0015]FIG. 1 depicts a schematic representation of typical prior art home distribution system in which two analog televisions are directly connected to a cable network system and two analog televisions are connected to the cable network system through digital set-top box.  
         [0016]    [0016]FIG. 2 depicts a schematic representation of a home media server directly connected to an entry point device to the cable network system as known in the prior art.  
         [0017]    [0017]FIG. 3 depicts a block diagram of one embodiment of the present invention.  
         [0018]    [0018]FIG. 4 depicts a more detailed schematic drawing of the embodiment shown in FIG. 3, illustrating a home media server, a passive entry point device and a reflector, each connected to home distribution network. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]    Referring to FIG. 1, a typical home distribution network known to the prior art includes an entry point  10  which provides input from an external cable network. The signals from the entry point  10  are distributed by way of a plurality of splitters  14 ,  14 ′,  14 ″,  14 ′″ (generally  14 ) over coaxial cables to a plurality of televisions  18 ,  18 ′,  18 ″,  18 ′″ (generally  18 ) either through a direct connection ( 18 ,  18 ′″) or through a digital set-top box  20 ,  20 ′ (generally  20 ).  
         [0020]    When a home media server  24  is included in the network (FIG. 2) it can be directly connected to the first splitter  14  and, optionally, can communicate with a thin-client  28  through the home distribution network. For this arrangement to function properly, the home media server  24  has to be placed in a room which has a direct coaxial connection to the first splitter  14 . If the home media server  24  is connected to the home distribution network at a splitter which is not located at the entry point  10  (such as  14 ′″), the home distribution network can cause problems that legacy digital set-top boxes are not designed to support. For example, such an arrangement can lead to the production of multipath effects. Further, if a set-top box and the home media server are connected to the same splitter and the splitter isolation is not sufficient, the signal transmitted from the home media server can interfere with the digital set-top box signal.  
         [0021]    In brief overview, an embodiment of a new system which avoids these problems is shown in FIG. 3. In this embodiment, a connection to the external cable network  10  is made through an entry point device  32  which splits the cable network signal. Part of the signal is sent to an active reflector  36 , which is connected directly to the entry point device  32 . The remaining signal is sent to the home distribution network  40 . Digital set-top boxes  20 , analog televisions  18  and the home media server  24  can reside anywhere in the house, and can be moved to other coaxial cable outlets as desired.  
         [0022]    In this embodiment, the home media server  24  transmits a legacy digital set-top box signal as well as a home network signal to networked thin-client devices at frequencies above 960 MHz. At the active reflector  36 , the legacy set-top box signal is shifted to any video channel in the frequency band 750-860 MHz, a band that is usually not used inside the house, and is transmitted back into the house and received by the legacy digital STBs. In this embodiment, there is no multipath problem for legacy signals. Accordingly, any existing digital set-top box can receive and properly decode the legacy signal transmitted from the home media server  24 . As each new thin-client device is installed, it is tuned to the home network frequencies.  
         [0023]    Two preferred embodiments enable for the set-top boxes to receive legacy signals from the home media server. In the first embodiment, legacy signals comprise frequencies above 960 MHz. In the second embodiment, the network uses different frequencies to and from the active reflector  36 . In this second embodiment, transmissions to the active reflector  36  comprise frequencies above 960 MHz, while transmissions from the active reflector  36  comprise frequencies between 750 MHz to 860 MHz. The shifting of the frequency of signals toward the active reflector  36  to the frequency of the signals from the active reflector  36  is performed by the active reflector  36 .  
         [0024]    In more detail and referring to FIG. 4, the embodiment shown includes a home media server  24 , a passive entry point device  32  and an active reflector  36  connected to the home distribution network coaxial wiring  40  and the external cable network  10 . Also connected to the home distribution network  40  are also one or more legacy set-top boxes  20 , cable modems  42 , and/or analog televisions  18 . Signals from the cable network  10  enter the home distribution network  40  through the passive entry point device  32 . Signals entering or leaving the home distribution network  40  preferably fall within two bands: 5-42 MHz. for transmitting signals from the home distribution network  40  to the cable supplier head end; and 55-860 Mhz. for video signals from the cable network  10 .  
         [0025]    In the preferred embodiment, the passive entry point device  32  includes a low pass filter  48  and a directional coupler  52 . In another embodiment, the entry point device  32  can comprise a demarcation point unit, for example, of the type described in co-pending U.S. patent application Ser. No. 10/234,358 entitled “Home Network and System and Method” by Kliger et al. (the “&#39;358 patent”), the entirety of which is incorporated by reference herein. As described therein, the demarcation point unit preferably includes a blocking filter that receives a home network signal from the home network backbone and an external signal from the external network. The blocking filter separates the home network signal from the external signal, and returns the home network signal back to the home network backbone. In another embodiment, the demarcation point unit preferably includes a diplexer and signal reflector. The diplexer receives a home network signal from the home network backbone and an external signal from the external network. The diplexer separates the home network signal from the external signal. Further, the systems and methods described herein are designed to compliment and be used with the network, systems, methods and components of the &#39;358 patent.  
         [0026]    The signals preferably enter through the low pass filter  48  which passes both bands of the incoming signal to the directional  91  coupler  52 . The directional coupler  52  preferably includes two output terminals. One of the directional coupler output terminals  56  is connected to the home distribution network  40 . A second output terminal  58  is preferably connected to input terminal  62  of the active reflector  36 . In various embodiments, the active reflector  36  can be physically located either at the entry point device  32  or within another room that is connected to the entry point device  32  through a coaxial cable, so long as there are no splitters  14  between the entry point device  32  and the active reflector  36 .  
         [0027]    Preferably, the home media server  24  includes a diplexer  66 , an RF section  70 , a digital signal processor  74  and a controller  78 . The controller  78  preferably integrates the functionality of the home media server  24  with the video distribution functionality described below. In this embodiment, signals passing through the home distribution network  40  enter the home media server  24  through a diplexer  66 . The 5-42 Mhz control signals transmitted from the legacy set-top box  20  enter the diplexer  66  and are amplified by a high impedance amplifier  82  in the RF section  70  prior to being digitized by an A/D converter  86  in the digital signal processor  74 . The digital output from the A/D converter  86  is the input signal to a quadrature phase shift key receiver  90  which is connected to the controller  78  through a Control interface.  
         [0028]    MPEG signals from the controller  78  are preferably sent to an MPEG modulator and frequency shift key modulator  94 . The result signals are then preferably converted by two D/A converters  98  and passed into a pair of high impedance amplifiers  102  in the RF section  70 . Signals from these amplifiers  102  are passed to a quadrature modulator  106 . A third input into the quadrature modulator  106  is a signal from a synthesizer  110 , preferably between about 958 and 1058 Mhz. The synthesizer  110  is preferably driven by at least two signals. One signal is from an oscillator  114  and the second signal is from varicap and resonator pair  118 . The output of the quadrature modulator  106  preferably becomes the input to an adjustable gain amplifier  122  whose output is in turn connected to another input terminal of the diplexer  66 .  
         [0029]    Signals from the home media server  24  (preferably above about 960 MHz) pass over the coaxial wiring to the passive entry point device  32  but are prevented from entering the external cable network  10  by the low pass filter  48 . These signals instead pass to the active reflector  36 .  
         [0030]    The signals enter the active reflector  36  by way of a diplexer  130 . In the preferred embodiment, signals in about the 960-1060 MHz. range are passed to a variable amplifier  132  whose output is connected to an input terminal of a multiplier  134 . The second input terminal of the multiplier  134  is connected to a synthesizer  138 . The synthesizer  138  preferably has at least one input connected to an oscillator  142  and at least one input connected to a varicap and resonator circuit  146 . The output of the multiplier  134  is the input signal to an amplifier  150 . The output of the amplifier  150  is connected to a frequency shift key receiver  154  and controller  154  and to a surface acoustic wave filter having a bandwidth of about 6 Mhz. at about 140 Mhz.  
         [0031]    The output of the surface acoustic wave filter  158  preferably forms the input signal to an amplifier  162 . The amplifier  162  output preferably forms one input to a multiplier  166 . The second input to the multiplier  166  is preferably formed by the output of a second synthesizer  172  whose input signals are from the oscillator  142  and a second varicap and resonator circuit  176 . The output of the multiplier  166  preferably forms the input to a variable amplifier  180  whose output is the input signal to the diplexer  130 .  
         [0032]    In the operation of the preferred embodiment, the home media server  24  transmits its MPEG video signal at a frequency above the CATV signal (above 960 MHz) in the same format and modulation scheme as the head end of the external CATV network  10 . This signal reaches the passive entry point device  32 , from which it is forwarded to the active reflector  36 . The active reflector  36  receives and down-converts the signal to the IF frequency, filters the TV signal and up-converts the TV signal to a predefined TV band (between 750 MHz and 860 MHz). The active reflector  36  then amplifies the TV signal according to control signals the active reflector  36  receives from the home media server  24  so that the level of the reflected signal will be equal to the level of the TV signals from the head end of the external cable network  10 . In this embodiment, the legacy digital set-top box  20  can now receive MPEG2 video generated by the home media server  24 , when the set-top box is tuned to a specific video channel. Alternatively, the legacy digital set-top box  20  can receive regular CATV programs when tuned to any other video channel. The channel used by the home media server video can not be the same channel as used by the head end of the external cable network  10 .  
         [0033]    In order to control frequency bands and gains used by the active reflector  36 , a low bit-rate frequency shift key control channel is established between the home media server  24  and the active reflector  36  using the frequency shift key receiver and control  154  described above. In order to lock the receiver  154  to the changeable frequency, the home media server  24  preferably transmits a barker series or other chipping sequence continuously. The receiver  154  at the active reflector  36  searches until the receiver  154  detects and locks onto the designated frequency.  
         [0034]    At initialization, the home media server  24  preferably selects an RF transmission frequency in the band of approximately 960 MHz-1060 MHz. The home media server  24  also selects a CATV channel frequency in the band between about 750 MHz-860 MHz. The home media server  24  then transmits control information on the selected control frequencies to the active reflector  36 . Then the home media server  24  finds the RF received level of the CATV signals from the head end of the cable network  10  and transmits a default MPEG-TS video. The home media server  24  receives the TV signal and sends correction commands to the active reflector  36  until the correct gain is achieved.  
         [0035]    It will be appreciated that the embodiments described above are merely examples of the invention and that other embodiments incorporating variations therein are considered to fall within the scope of the invention.