Abstract:
A circuit, electrical device or other apparatus for band stacking and/or band translating multiple transmissions. Such transmissions may be satellite transmissions, terrestrial transmissions, signals carried across a wired network such as a cable network, and so forth. Two sets of left-hand polarized and right-hand polarized signals may be accepted by an embodiment. One left-hand polarized signal and one right-hand polarized signal may be band stacked such that the left-hand polarized signal occupies a first frequency and the right-hand polarized signal occupies a second frequency, thereby permitting the two signals to be transmitted simultaneously across a single transmission line as a first unique signal. The second left-hand polarized signal and second right-hand polarized signal may likewise be combined into a second unique signal for transmission. The first and second unique signals may be stacked as a first stacked output and a second stacked output by a band translating circuit.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 12/062,254, entitled “Low Noise Block Converter Feedhorn”, filed on Apr. 3, 2008, now U.S. Pat. No. ______, which is hereby incorporated by reference herein in its entirety. 
         [0002]    This application incorporates the following applications by reference as if fully set forth herein: U.S. patent application Ser. No. 11/256,472, filed Oct. 20, 2005; and U.S. patent application Ser. No. 11/140,330, filed May 27, 2005, both naming Edmund F. Petruzzelli as inventor. 
     
    
     TECHNICAL FIELD 
       [0003]    Embodiments of the present invention relate generally to low noise block converter feedhorns for use in a satellite broadcast/reception system, and more particularly to a band-translating low noise block converter feedhorn having a single local oscillator. 
       BACKGROUND 
       [0004]    Modern tuning devices, such as those used in set top boxes to receive satellite transmissions, often have multiple tuners. The use of multiple tuners permits a set top box to perform several functions that would otherwise be difficult or impossible. For example, a multi-tuner set top box may display a picture-in-picture output or may record one program while another is sent from the set top box for display on a display device. 
         [0005]    Multi-tuner set top boxes typically employ band stacking and translation to process multiple signals originating from multiple sources, such as two or more satellite transmitters. Briefly, band stacking is the process of placing two discrete signal bands on a single cable. The discrete signals occupy different frequencies of the input and are often separated by a guard zone, which is a frequency band containing no signal data. Band translation is the operation of combining band stacked signals into one or more outputs and may include, for example frequency mixing and/or frequency translating of one or more signals. 
         [0006]    For example, if a set top box has two tuners, it may receive signals from two separate satellites. Each satellite generally transmits a left-hand circular polarized signal and a right-hand circular polarized signal. Thus, if a set top box has two tuners, it may receive four signals—two from each satellite. The two signals from each satellite may be band stacked into a single input signal, thus yielding two input signals in total (one for each satellite). These band stacked signals may then be translated to yield two different stacked outputs. The first stacked output may contain, for example, the left-hand circular polarized feed from each of the first and second satellites while the second stacked output may contain the right-hand circular polarized feed from each of the satellites. Band stacking and band translation are more thoroughly described in U.S. patent application Ser. No. 11/256,472, filed Oct. 20, 2005; and U.S. patent application Ser. No. 11/140,330, filed May 27, 2005, both naming Edmund F. Petruzzelli as inventor. 
         [0007]    The process of band stacking generally requires a relatively high-frequency signal produced by a local oscillator in a low noise block converter feedhorn (“LNBF”) of a customer&#39;s receiving system. However, accurate high-frequency local oscillators can be expensive. Further, it is more difficult to produce an accurate high-frequency local oscillator than a low-frequency local oscillator, and high-frequency local oscillators may have a shorter service life. Accordingly, there is a need in the art for an improved low noise block converter feedhorn. 
       SUMMARY 
       [0008]    Certain embodiments may take the form of a circuit, electrical device or other apparatus for band stacking and/or band translating multiple transmissions. Such transmissions may be, for example, satellite transmissions, terrestrial transmissions, signals carried across a wired network such as a cable network, and so forth. One example of an apparatus embodying an exemplary embodiment is a low noise block feedhorn. 
         [0009]    As one example, two sets of left-hand polarized and right-hand polarized signals may be accepted by an embodiment. One left-hand polarized signal and one right-hand polarized signal may be band stacked such that the left-hand polarized signal occupies a first band frequency and the right-hand polarized signal occupies a second frequency, thereby permitting the two signals to be transmitted simultaneously across a single transmission line as a first unique signal (e.g., the two may be combined into a single signal). The second left-hand polarized signal and second right-hand polarized signal may likewise be combined into a second unique signal for transmission. 
         [0010]    The first and second unique signals may be stacked as a first stacked output and a second stacked output by a band translating circuit. 
         [0011]    One embodiment may take the form of a low noise block converter feedhorn, comprising: a signal receiver operative to receive at least a first input signal and a second input signal; a first mixer operative to receive the first input signal from the signal receiver, further operative to mix the first input signal with a first reference signal to create a first translated signal; and a second mixer operative to receive the second input signal from the signal receiver, further operative to mix the second input signal with the first reference signal to create a second translated signal; a third mixer operative to mix the first translated signal with a second reference signal to create a third translated signal; and a first combiner operative to stack the third translated signal and second translated signal into a first single stacked signal. 
         [0012]    Another embodiment may take the form of a method for converting at least a first incoming transmission and a second incoming transmission to an outgoing transmission, comprising the operations of: receiving a first incoming transmission; receiving a second incoming transmission; multiplexing the first incoming transmission with a first reference signal to create a first multiplexed signal; multiplexing the second incoming transmission with a second reference signal to create a second multiplexed signal; multiplexing the second multiplexed signal with a third reference signal to create a third multiplexed signal; and diplexing the second and third multiplexed signals to create a first band-stacked signal. 
         [0013]    Yet another embodiment may take the form of an apparatus for converting at least one right-hand polarized signal and at least one left-hand polarized signal into a stacked output, comprising: a first signal receiver for receiving a first right-hand polarized signal and a first left-hand polarized signal; a first signal generator; a first multiplexer electrically connected to the first signal generator and the first signal receiver; a second multiplexer electrically connected to the first signal generator and the first signal receiver; and a band translating circuit electrically connected to the first and second multiplexers, the band translating circuit outputting at least a first stacked output. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    Various details of the embodiments disclosed herein may be better understood on reading the following detailed description of non-limiting embodiments, and on examining the accompanying drawings, in which: 
           [0015]      FIG. 1  is an exemplary block diagram illustrating components of an example of a broadcast satellite television system; 
           [0016]      FIG. 2  is a block diagram of a multiple-satellite band translating system connected to a dual-tuner television converter device; 
           [0017]      FIG. 3  is a block diagram of a multiple-satellite band translating system connected to a multiple-tuner television converter device in accordance with an embodiment; 
           [0018]      FIG. 4  is a block diagram of a low noise block converter embodiment employing a band translating system; 
           [0019]      FIG. 5  is a first block diagram of a low noise block converter embodiment employing a band translating system incorporating a multiplexed signal to generate band stacked signals, in accordance with an embodiment; 
           [0020]      FIG. 6  is a second block diagram of a low noise block converter embodiment employing a band translating system incorporating a multiplexed signal to generate band stacked signals, in accordance with an embodiment; 
           [0021]      FIG. 7  is a third block diagram of a low noise block converter embodiment employing a band translating system incorporating a multiplexed signal to generate band stacked signals, in accordance with an embodiment; and 
           [0022]      FIG. 8  is a fourth block diagram of a low noise block converter embodiment employing a band translating system incorporating a multiplexed signal to generate band stacked signals, in accordance with an embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    In this specification, embodiments will be described using methods and systems related to subscriber satellite television service. This detailed description is not limited to any specific embodiment described herein. Various embodiments may also be applicable to cable television systems, broadcast television systems or other television systems. Certain embodiments are also described in terms of digital video recorder (DVR) devices. These embodiments may also be applicable to digital versatile disc (DVD) recording devices or other television recording devices. It should be understood that embodiments can apply elsewhere, such as in personal computing devices (handheld or otherwise). While the various embodiments have been particularly shown and described, it should be appreciated that various other changes in the form and details may be made therein without departing from the spirit and scope of the invention. 
         [0024]    As a general matter, the disclosure uses the term “signal.” The referenced signal may be any digital or analog signal. Accordingly, signals may include, but are not limited to, a bit, a specified set of bits, an A/C signal, or a D/C signal. Uses of the term “signal” in the description may include any of these different interpretations. It should also be understood that the term “connected” is not limited to a physical connection but can refer to any means of communicatively or operatively coupling two devices. 
         [0025]    As another general matter, the disclosure uses the terms “television converter,” “receiver,” “set-top-box,” “television receiving device,” “television receiver,” “television recording device,” “satellite set-top-box,” “satellite receiver,” “cable set-top-box,” “cable receiver,” and “television tuner” to refer interchangeably to a converter device or electronic equipment that has the capacity to acquire, process and distribute one or more television signals transmitted by broadcast, cable, telephone or satellite distributors. DVR and “personal video recorder (PVR)” refer interchangeably to devices that can record and play back television signals and that may implement trick functions including, but not limited to, fast-forward, rewind and pause. As set forth in this specification and the figures pertaining thereto, DVR and PVR functionality or devices may be combined with a television converter. The signals transmitted by these broadcast, cable, telephone or satellite distributors may include, individually or in any combination, internet, radio, television or telephonic data or information. A television converter device may be implemented as an external self-enclosed unit, a plurality of external self-enclosed units or as an internal unit housed within a television. Further, various embodiments described herein can apply to analog and digital satellite set-top-boxes. 
         [0026]    As yet another general matter, as used here, the term “television” refers to a television set or video display that may contain an integrated television converter device (e.g., an internal cable-ready television tuner housed inside a television) or, alternatively, that is connected to an external television converter device (e.g., an external set-top-box connected via cabling to a television). A further example of an external television converter device is the EchoStar Dish PVR 721, Part Number 106525, combination satellite set-top-box and DVR. 
         [0027]    It should also be understood that satellite television signals may be very different from broadcast television or other types of signals. Satellite signals may include multiplexed, packetized, and modulated digital signals. Once multiplexed, packetized and modulated, one analog satellite transmission may carry digital data representing several television stations or service providers. Some examples of service providers include HBO®, CSPAN®, ABC®, CBS®, or ESPN®. 
         [0028]    Further, the term “channel,” as used in this description, may employ a different meaning from its normal connotation. The term “channel” is used herein to denote a particular carrier frequency or “sub-band” which can be tuned to by an appropriate tuner. In particular, note that “channel” does not refer to a single program/content service (e.g., CNN®, HBO®, CSPAN®). Similarly, “tuning” herein refers to receiving a channel (as previously defined) having multiple services thereon. A single satellite will typically have multiple transponders (e.g., 32 transponders) each one broadcasting a channel or band of approximately 24 to 27 MHz (0.024-0.027 GHz) in a broader frequency “band” of approximately 500 MHz. Thus a band of 0.5 GHz may contain numerous sub-bands or channels of roughly 24-27 MHz and each channel in turn may carry a combined stream of digital data comprising a number of content services. 
         [0029]    The block diagrams shown in the various Figures of this description are for illustration only and are not intended to represent the only possible process flows and system configurations. In particular, it should be understood that operations may be added, omitted and recorded as may be suitable to a particular application. Also, individual components may be added, omitted, replaced and interrelated as may be suitable to a particular application. All details appurtenant to implementing the exemplary systems and methods that are well understood in the art are omitted for simplicity and clarity. 
         [0030]      FIG. 1  is a simplified block diagram illustrating components of an example of a broadcast satellite television system that may be used to implement various features described herein. In particular,  FIG. 1  generally illustrates a client device  100  as part of a satellite broadcast system. In this example, a broadcast service  170  provides programs and program information, via one or more satellites  160 , to the client device  100 . The broadcast service  170  may include a processor  172 , which is discussed further below. The client device  100  may include suitable circuitry, other hardware and/or software to receive a signal(s) from the satellite(s)  160 , such as a satellite dish or antenna (not shown). 
         [0031]    The signal(s) from the satellite(s)  160  may carry multiple channels of programs, program information (such as electronic programming guide data), and/or other information, such as conditional access data. The signal(s) from the satellite(s)  160  received at the client device  100  may be processed such that the data and/or the channels may be viewed on a display device  150 , such as a television set or monitor. 
         [0032]    The client device  100  may include a first tuner unit  102  and a second tuner unit  104 , each of which may comprise a tuner, a demodulator, and any other device or circuitry for selecting channels and modifying the data format for processing and/or displaying on the display device  150 . While one of the first and second tuner units  102 ,  104  is selected for displaying programs and/or program information on the display device  150 , the other of the first and second tuner units  102 ,  104  may be considered to be latent (with respect to displaying data). It should be understood that any number of tuner units may be employed, with such units not currently being used for displaying being considered latent. 
         [0033]    The client device  100  may also include a processor  106  for controlling various operations of the client device  100  and/or the other components thereof. The client device  100  may also include a storage device  110 , which may have a program and/or associated data stored thereon, in addition or alternatively to such program and/or data rendered on the display device  150 . The storage device  110  may also be used to store user preferences, set-up information and/or other criteria  112 , as discussed further below, usually specific to the client device  100 . 
         [0034]    Regardless of the particular implementation of the client device  100  and/or the broadcasts system in general, a system for selectively receiving at least part of a program based on events that occur in the program is contemplated. In operation, as discussed above, one of the first and second tuner units  102 ,  104  may be currently presenting a program for display and the other may be considered to be latent. The latent tuner unit may be used to monitor either an audio stream or a video stream, or both, of a program that is being transmitted on a channel to which the latent tuner unit is set. 
         [0035]    It should be understood that the non-latent tuner unit may also be used to monitor the audio stream and/or video stream of the program being received thereby, but such is not described for the sake of simplicity and brevity. Such an approach may allow a user to view a program and to selectively record the program or part of the program as described herein with respect to the latent tuner unit. 
         [0036]    As a general, simplified example, a program received by the first tuner unit  102  may be displayed and the second tuner unit  104  may be considered to be latent. The processor  106  of the client device  100  and/or the processor  172  of the broadcast service  170  may be configured to monitor programs received by the second tuner unit  104 . For the sake of simplicity and brevity, operation of the processor  106  of the client device  100  is described herein. However, it should be understood that any or all client-side operations may be performed as broadcast service-side operations, as appropriate or desired. 
         [0037]      FIG. 2  presents a block diagram of a multiple-satellite band translating system connected to a dual-tuner television converter device.  FIG. 3  then presents a block diagram of a multiple-satellite band translating system connected to a multiple-tuner television converter device in accordance with a particular embodiment described herein.  FIGS. 2 and 3  represent only two examples of the n-number of tuner configurations that are possible using band translation technology. It should also be understood that the arbitrary, n-number of tuner configurations do not require an even number of tuners and that band translation for an odd number of tuners is also possible and within the scope of this document. Further, the n-number of tuners may reside in devices (e.g., a personal computer) other than a television converter device in the form of a satellite set-top box (“STB”). 
         [0038]    Band translation switch  202  is connected to dual tuner television converter device  204  via separator  206 . Cascade outputs (not shown) from band translation switch  202  allow band translation switch  202  to be connected with other band translation switches or conventional switches. 
         [0039]    Band translation switch  202  receives RF input from four satellite dishes  210 ,  212 ,  214  and  216 . Band translation switch  202  might be connected to a lesser or greater number of such satellite dishes. In the embodiment shown in  FIG. 2 , each satellite dish points to a different satellite. Dish  210  points to a satellite located at 119 degrees west longitude, dish  212  points to a satellite located at 110 degrees west longitude, dish  214  to a satellite located at 61.5 degrees west longitude and dish  216  to a satellite located at 148 degrees west longitude. All four satellites in this particular embodiment are in geosynchronous orbit (e.g., zero degrees latitude, low or zero eccentricity and 40,000 kilometers orbital radius with no relative angular velocity relative to a point on the surface of the Earth). However, should DBS systems evolve to include the ability of satellite dishes to track moving satellites (for example, the Molniya system) the band translation switch  202  may still be used without alteration. The band translation switch  202  may also be used without alteration in other television systems or communication systems now known or later developed, as circumstances require. 
         [0040]    The output from exemplary dish  210  is sent to power divider  218 . In the embodiment depicted in  FIG. 2 , power divider  218  is a four way power divider, supporting a total of four tuners, for example, two television converter devices each having dual tuners. However, the power dividers of band translation switch  202  may be scaled from four outputs to six, allowing switch  502  to support up to six tuners, such as would be present in a three dual-tuner television converter device system. 
         [0041]    The outputs from the power dividers  218  are sent to source selection switches  220  and  222 . In one embodiment, two additional source selection switches (not pictured) are also present in band translation switch  202 . Every source selection switch receives the signals from every satellite dish  210 ,  212 ,  214 , and  216 , in this embodiment. Note that since the signals received are polarized (left-hand, right-hand, vertical, horizontal or other polarization), each dish is actually bandstacking and sending to the source selection switches  220 ,  222  two pre-stacked bands of data. Thus in this embodiment source selection switch  220 , for example, may be receiving up to eight 0.5 GHz wide bands of data (two bands per satellite dish) but will be selecting the output from one satellite only (two bands of data) for transmission to the next stage of processing. 
         [0042]    The output from source selection switch  220  goes to low band translator  224  (LBT). LBT  224  includes signal path switch  228  allowing bypass of the low band translation function, depending upon which band of the two pre-stacked bands received from switch  220  is the desirable band. If translation is desired, signal path switch  228  causes band translation at frequency mixer  238 . If translation of the frequency bands is not desired, signal path switch  228  will bypass frequency mixer  238  and the translation function will not occur. 
         [0043]    Translation is accomplished in frequency mixer  238  by summation-difference with a 3.1 GHz signal obtained from clock/frequency generator  232 , which may be made of a phase locked loop  234  and an oscillator  236 . (In some embodiments, only the phase locked loop or the oscillator are present in the generator  232 ). The translated or bypassed band is then passed through low pass filter  242  (LPF). LPF  242  ensures that the signal sent from low band translator  224  is cut off beginning at approximately 1450 MHz. In present embodiment, the operative connection from low band translator  224  to frequency stacker  246  is by way of LPF  242 , with such circuitry, wiring or cables as is in turn required between these components, however, in other embodiments the operative connection may be only circuitry, wiring, coaxial cable or other cabling. 
         [0044]    In a like manner, the output from satellite selector switch  222  is sent to high band translator  226 . Switch  230  either sends the signal to frequency mixer  240  (once again driven by local oscillator  236 ) or bypasses the high band translation operation. The output from high band translator  226  is sent to high pass filter  244  which cuts off frequencies below approximately 1650 MHz. 
         [0045]    Note that signal path switches  228  and  230  thus have at least two positions: first positions in which band translators  224  and  226  are in the circuit; and second positions in which signal path switches  228  and  230  cause the band translators  224  and  226  to be bypassed, in which case the translators are said to be “out of the circuit.” 
         [0046]    The two signals are combined after LPF  242  and HPF  244  in frequency stacker  246 , then sent to separator  206 . The tuner  247  is programmed to accept frequencies from 950 MHz to 1450 MHz while tuner  250  is programmed to accept frequencies from 1650 MHz to 2150 MHz, effectively re-dividing the signal on that basis. The 0.2 GHz bandwidth between 1450 MHz and 1650 MHz is referred to as a “guard band” and usually contains the quickly degrading frequencies cut off by LPF  242  and HPF  244 : these cut off frequencies may drop by many dB before crossing the guard bandwidth, at which reduced level they do not significantly impact the signal being read by the other tuner. 
         [0047]    In operation, tuners  248  and  250  may signal to band translation switch  202  a satellite and polarity on which may be found the desired service for each tuner. (In alternative embodiments, one tuner may transmit all commands discussed herein while the second tuner passively receives data and/or responds to the first tuner&#39;s commands, thus acting as a slave tuner.) Source selection switches  220  and  222  may each select the proper satellite dish, which may be the same or a different dish. Each satellite switch  220 ,  222  will pass both bands from the selected satellite (pre-stacked from the different polarity signals sent on the same frequency to the dishes) to the band translators  224 ,  226 . Low band translator  224  generally determines if the signal to be sent to tuner  248  is already in the lower (950-1450 MHz) band and if so, it will bypass translation and simply send the signal to LPF  242 , which will filter out the higher frequency band. However if the signal is in the higher frequency band of 1650-2150 MHz, then signal path switch  228  will send the signal to frequency mixer  238  to down-convert the frequency of the desired signal to the lower band. (Note that in this event, the undesired lower frequency signal will have its frequency reduced from the lower band to an even lower frequency range (sub 950 MHz), below what tuner  248  recognizes.) 
         [0048]    High band translator  226  (HBT) will carry out the converse process: it generally determines if the signal to be sent to tuner  250  is already in the higher band and if so, will bypass high band translation and simply send the signal to HPF  244 . On the other hand, if the signal which is desired by tuner  250  (programmed to accept the higher frequency band) is in the lower frequency band, then switch  230  will send the signal to frequency mixer  240  to up-convert the frequency of the desired signal to the higher range. In this case, the higher of the two bands sent to HBT  226  will be translated to a value above the highest frequency (2.15 GHz) which tuner  250  typically does not recognize. 
         [0049]    The result is that either tuner may request any frequency band from any satellite and yet receive it in the frequency range for which that tuner has already been programmed, thus eliminating the need for television converter device  204  to accept frequency bands as they arrived from the satellite dishes. 
         [0050]    While only one television converter device  204  is shown, band translation switch  202  equipped with four-way power dividers  218 , for example, that can support two entirely independent dual tuner television converter devices via additional source selection switches, LBT, LPF, HBT, HPF and a frequency stacker. As stated earlier, by means of six-way power dividers, three dual tuner television converter devices could be supported. It should be appreciated that several n-tuner configurations are possible. 
         [0051]    Note that LPF  242 , HPF  244  and frequency stacker  246  effectively amount to a diplexer. However, band translation switch  202  may have additional circuitry (intermediate band translators, intermediate bandpass filters, etc.) so as to function as a multiplexer; that is, to stack more than two bands into the output frequencies. Such a configuration might require tuners having additional spectrum recognition abilities and/or constraints on the use of coaxial cable (which might have shorter allowable runs, additional features to increase bandwidth or may be replaced with other forms of connection) but would not exceed the scope of the invention as claimed herein. In such a system, band translation switch  202  may support more than two tuners in a single television converter device on a single coaxial cable. For example, a first frequency band and a second frequency band of a single coaxial cable may be sub-divided so as to contain two frequency bands in each of the first and second frequency bands. In this example, four tuners in a single television converter device may then receive the four output frequency bands. Band translation switch  202  may also be reconfigured to support multiple-tuner television converter device configurations. 
         [0052]    In operation, it is possible that the two bands stacked for transmission to the dual tuner television converter device might come from different satellites or the same satellites, or might even be the same band, bandstacked onto itself. The original frequencies of the two bands may even become reversed in the band translation switch. In any embodiment, however, each tuner can receive its desired band in the frequency band it is pre-programmed to receive. Each tuner then performs RF tuning to the appropriate sub-band/channel, demodulating and demultiplexing; and digitally processing the chosen program service from among those program services on the channel. 
         [0053]    The control system of switch  202  is also depicted. In operation, control signal detection and transmission interface  252  will detect control signals sent by tuners  248  and  250  and cooperate with microcontroller  254 . In the present two-tuner embodiment, the control signals sent by tuners  248  and  250  will be designated as master and slave. For example, a master or primary control signal may be sent by tuner  248 , while a slave or secondary signal is sent by tuner  250 . Alternatively, the second tuner  250  may transmit nothing and merely receive data. Designation of control signals as master and slave may reduce the processing time of the control signal detection and transmission interface  252  and microcontroller  254 . In another embodiment, the control signals sent by tuners  248  and  250  may operate independently. Microcontroller  254  has control authority over signal path switches  228  and  230 , satellite selection switches  220  and  222  and control signal detection and transmission interface  256 . Interface  256  may be a second control signal detection and transmission interface separate from interface  252 , or in alternative embodiments the two structures may be combined. For example, the mere presence or absence of a signal may be used, respectively, to indicate a master or slave primary control signal. 
         [0054]    In operation, signals sent from tuners  248  and  250  are used by microcontroller  254  to control the satellite selection switches  220  and  222 ; by this structure the appropriate satellite signals are sent to LBT  224  and HBT  226 . Microcontroller  254  also controls signal path switches  228  and  230  independently from each other in order to determine whether band translation occurs in each translator; as a result of this, the band requested by tuners  248 ,  250 , arrives at the tuner in the correct frequency band. In addition to signals sent from tuners  248 ,  250  to microcontroller  254 , other signals are sent from tuners  248 ,  250  having preambles which indicate that they are to be passed through to the low noise block feedhorn (LNBF) at the satellite dish. 
         [0055]    As set forth earlier,  FIG. 3  depicts a block diagram of a multiple-satellite band translating system connected to a multiple-tuner television converter device in accordance with an exemplary embodiment. 
         [0056]    Band translation switch  302  is connected to a four tuner television converter device  304  via separator  306 . Cascade outputs  334  from band translation switch  302  allow band translation switch  302  to be connected with other band translation switches or conventional switches in a manner similar to the embodiment previously discussed with reference to  FIG. 2 . 
         [0057]    Band translation switch  302  receives RF input from four satellite dishes  310 ,  312 ,  314  and  316 . Band translation switch  302  might be connected to a lesser or greater number of such satellite dishes. In the embodiment shown in  FIG. 3 , each satellite dish points to a different satellite. Dish  310  points to a satellite located at 119 degrees west longitude, dish  312  points to a satellite located at 110 degrees west longitude, dish  314  to a satellite located at 61.5 degrees west longitude and dish  316  to a satellite located at 148 degrees west longitude. All four satellites in this particular embodiment are in geosynchronous orbit, as defined above. However, should DBS systems evolve to include the ability of satellite dishes to track moving satellites (for example, the Molniya system) the band translation switch  302  may still be used without alteration. The band translation switch  302  may also be used without alteration in other television systems or communication systems now known or later developed, as circumstances require. 
         [0058]    The output from exemplary dish  310  is sent to power divider  308 . In the embodiment depicted in  FIG. 3 , power divider  308  is a four-way power divider and supports a total of four tuners in a single television converter device. It should be understood, however, that n-number of tuners is possible and that placement of the n-number of tuners need not occur in the same television converter device. For example, two television converter devices may each have dual tuners. Likewise, the power dividers of band translation switch  302  may also be scaled from four outputs to six, allowing switch  302  to support up to six tuners, such as would be present in a three dual-tuner television converter device system. 
         [0059]    The outputs from the power dividers, such as power divider  308 , are sent to source selection switches  326 ,  328 ,  330 , and  332 . Every source selection switch receives the signals from every satellite dish  310 ,  312 ,  314 , and  316 , in this embodiment. Note that since the signals received are polarized (left-hand, right-hand, vertical, horizontal or other polarization), each dish is actually bandstacking and sending to the source selection switches  326 ,  328 ,  330 , and  332  four pre-stacked bands of data or a bank of independent polarization bands. Thus in this embodiment source selection switch  326 , for example, may be receiving up to eight 0.5 GHz wide bands of data (two bands per satellite dish) but will be selecting the output from one satellite only (two bands of data) for transmission to the next stage of processing. 
         [0060]    The output from source selection switch  326  goes to low band translator (LBT)  336 . LBT  336  includes frequency mixer  338 . Band translation is accomplished in frequency mixer  338  by summation-difference with a signal obtained from low band oscillator unit (LBOU)  398 : a local oscillator path switch; a phase locked low band translation oscillator  376 ; a phase locked high band translation oscillator  378 ; and an oscillator control  382 . Local oscillator path switch  380  allows appropriate translation depending upon the desired band set forth by the oscillator control  382 . If high band translation is desired by the oscillator control  382 , phase locked translation oscillator  376  translates the signal using a frequency of approximately 2675 MHz to 3175 MHz and creates a signal at approximately 1025 MHz from frequency mixer  338 . If low band translation is desired by the oscillator control  382 , phase locked oscillator  378  converts the signal at a frequency of approximately 1975 MHz to 2475 MHz and creates a 1025 MHz signal from an output of the frequency mixer  338 . It should be appreciated that other band translation and bypass structures are possible within the LBOU. Further, several other translation and bypass signal oscillation frequencies are possible for use in various embodiments and fall within the scope of this disclosure. The translated band is then passed through band pass filter (BPF)  352 . BPF  352  ensures that the signal sent from low band translator  336  is cut off at frequencies below approximately 950 MHz and above 1100 MHz and passes the desired channel at 1025 MHz with little or no attenuation. 
         [0061]    In a like manner, the output from satellite selector switch  928  may be sent to a second band translator (SBT)  340 . SBT  340  includes frequency mixer  342 . Band translation is accomplished in frequency mixer  342  by summation-difference with a signal obtained from low mid-range band oscillator unit (LMBOU)  301 : a local oscillator path switch  391 ; a phase locked low band translation oscillator  384 ; a phase locked high band translation oscillator  386 ; and an oscillator control  388 . Local oscillator path switch  391  allows appropriate translation depending upon the desired band set forth by the oscillator control  388 . If high band translation is desired by the oscillator control  388 , phase locked translation oscillator  384  translates the signal using a frequency of approximately 3025 MHz to 3525 MHz and creates an approximately 1375 MHz signal from frequency mixer  342 . If low band translation is desired by the oscillator control  388 , phase locked oscillator  386  converts the signal at a frequency of approximately 2325 MHz to 2825 MHz and creates a 1375 MHz signal from frequency mixer  342 . Additionally, it should be appreciated other band translation and bypass structures may be implemented within the LMBOU and/or other embodiments. Further, several other translation and bypass signal oscillation frequencies are possible and within the contemplated scope. The translated band is then passed through low mid-range pass filter (LMPF)  354 . LMPF  354  ensures that the signal sent from SBT  340  is cut off at frequencies below approximately 1300 MHz and above 1450 MHz and passes the desired channel at 1025 MHz with little or no attenuation. 
         [0062]    Similarly, the output from satellite selector switch  330  is sent to a third band translator (TBT)  344 . TBT  344  includes frequency mixer  346 . Band translation is accomplished in frequency mixer  646  by summation-difference with a signal obtained from high mid-range band oscillator unit (HMBOU)  396 : a local oscillator path switch  372 ; a phase locked low band translation oscillator  368 ; a phase locked high band translation oscillator  370 ; and an oscillator control  374 . Local oscillator path switch  372  allows appropriate translation depending upon the desired band set forth by the oscillator control  374 . If high band translation is desired by the oscillator control  374 , phase locked translation oscillator  368  translates the signal using a frequency of approximately 3375 MHz to 3875 MHz and creates an approximately 1725 MHz signal from frequency mixer  346 . If low band translation is desired by the oscillator control  374 , phase locked oscillator  370  converts the signal at a frequency of approximately 2675 MHz to 3175 MHz and creates a signal at approximately 1725 MHZ from frequency mixer  346 . One skilled in the art will recognize that other band translation and bypass structures are possible within the HMBOU. Further, other translation and bypass signal oscillation frequencies are possible and within the scope of this document. The translated band is then passed through high mid-range pass filter (HMPF)  356 . HMPF  356  ensures that the signal sent from TBT  344  is cut off at frequencies below approximately 1650 MHz and above 1800 MHz and passes the desired channel at 1725 MHz with little or no attenuation. 
         [0063]    Finally, to describe the last translator of this embodiment, the output from satellite selector switch  332  is sent to a high band translator (HBT)  348 . HBT  348  includes frequency mixer  350 . Band translation is accomplished in frequency mixer  350  by summation-difference with a signal obtained from high band oscillator unit (HBOU)  395 : a local oscillator path switch  364 , a phase locked low band translation oscillator  360 , a phase locked high band translation oscillator  362  and an oscillator control  366 . Local oscillator path switch  364  allows appropriate translation depending upon the desired band set forth by the oscillator control  366 . If high band translation is desired by the oscillator control  366 , phase locked translation oscillator  360  translates the signal using a frequency of approximately 3725 MHz to 4225 MHz and creates an approximately 2075 MHZ signal from frequency mixer  350 . If low band translation is desired by the oscillator control  366 , phase locked low band translation oscillator  362  converts the signal at a frequency of approximately 3025 MHz to 3525 MHz and creates an approximately 2075 MHz signal from frequency mixer  350 . The translated band is then passed through high band pass filter (HBPF)  358 . HBPF  358  ensures that the signal sent from HBT  348  is cut off at frequencies below approximately 2000 MHz and above 2150 MHz and passes the desired channel at 2075 MHz with little or no attenuation. 
         [0064]    In the present embodiment, the operative connection from band translators  336 ,  340 ,  344  and  348  to frequency stacker  390  is by way of BPF  352 , LMPF  354 , HMPF  356  and HBPF  358 , with such circuitry, wiring or cables as are in turn required between these components, however, in other embodiments the operative connection may be only circuitry, wiring, coaxial cable or other cabling. 
         [0065]    The four signals are combined from BPF  352 , LMPF  354 , HMPF  356  and HBPF  358  in frequency stacker  390 ; the combined signal then is sent to splitter  306 . Tuner  318  is programmed to accept frequencies from 950 MHz to 1100 MHz (centered at 1025 MHz), tuner  320  is programmed to accept frequencies from 1300 MHz to 1450 MHz (centered at 1375 MHz), tuner  322  is programmed to accept frequencies from 1650 MHz to 1800 MHz (centered at 1725 MHz) and tuner  324  is programmed to accept frequencies from 2000 MHz to 2150 MHz (centered at 2075 MHz). (It should be understood that these frequencies, like all frequencies mentioned herein, are exemplary rather than limiting. Alternative embodiments may employ different tuner, translation, and/or other frequencies.) Each tuner  318 ,  320 ,  322 , and  324  effectively re-divides the signal by these frequency programming ranges. The 0.2 GHz bandwidth between 1450 MHz and 1650 MHz, for example, is referred to as a “guard band” and usually contains the quickly degrading frequencies cut off by LMPF  354  and HMPF  356 . These cut off frequencies may drop by many dB before crossing the guard bandwidth, at which reduced level they typically do not significantly impact the signal being read by the other tuner. 
         [0066]    In operation, tuners  318 ,  320 ,  322  and  324  will signal to band translation switch  302  which satellite and polarity on which may be found the desired service for each tuner. Source selection switches  326 ,  328 ,  330  and  332  will each select the proper satellite dish, which may be the same or a different dish. Each satellite switch  326 ,  328 ,  330  and  332  will pass both bands from the selected satellite (pre-stacked from the different polarity signals sent on the same frequency to the dishes) to the band translators  336 ,  340 ,  344 , and  348 . 
         [0067]    The result of the embodiment described above is that either tuner may request any frequency band from any satellite and yet receive it in the frequency range for which that tuner has already been programmed, thus eliminating the need for television converter device  604  to accept frequency bands as they arrived from the satellite dishes. 
         [0068]    Note that BPF  352 , LMPF  354 , HMPF  356 , BPF  358  and frequency stacker  390  effectively amount to a multiplexer; that is, more than two bands are stacked into multiple output frequencies. It should be appreciated that this multiplexer configuration typically requires tuners to have additional spectrum recognition abilities and/or constraints on the use of coaxial cable (which may have shorter allowable runs, additional features to increase bandwidth or may be replaced with other forms of connection) that are within the scope as set forth herein. In such a system, as is evident from  FIGS. 2 and 3 , a band translation switch may support more than two tuners in a single television converter device on a single coaxial cable. As is also evident from the drawings, band translation switches may also be reconfigured so as to support one or more single tuner television converter devices from a single coaxial cable carrying a signal from one or more satellite dishes. 
         [0069]    The control system of switch  302  is also depicted. In operation, control signal detection and transmission interface  392  will detect control signals sent by tuners  318 ,  320 ,  322  and  324  and cooperate with microcontroller  394 . In this embodiment, the control signals sent by tuners  318 ,  320 ,  322  and  324  operate independently. Several control signaling paradigms are possible in various embodiments. Microcontroller  394  has control authority over band translation oscillator control  366 ,  374 ,  382 ,  388  and control signal detection and transmission interface  397 . Interface  397  may be a second control signal detection and transmission interface separate from interface  392 , or in alternative embodiments the two structures may be combined. 
         [0070]    In operation, signals sent from tuners  318 ,  320 ,  322  and  324  are used by microcontroller  394  to control the low band translation oscillators  360 ,  368 ,  376 ,  384  and high band translation oscillators  362 ,  370 ,  378 ,  386 ; by this structure the appropriate satellite signals are sent to LBT  336 , SBT  340 , TBT  344  and HBT  348 . In addition to signals sent from tuners  318 ,  320 ,  322  and  324  to microcontroller  394 , other signals are sent from tuners  318 ,  320 ,  322  and  324  having preambles which indicate that they are to be passed through to the LNBF at the satellite dish. 
         [0071]    In particular, one of tuners  318 ,  320 ,  322  and  324  may request a particular channel or program, for example in response to a user input. The tuner then may instruct the microcontroller  394 , which is electrically connected to all switches  326 ,  328 ,  330 ,  332 , to determine which satellite input  310 ,  312 ,  314 ,  316  provides the desired channel or program. (Alternatively, the tuner itself may make this determination and pass the desired satellite input to the microcontroller.) The microcontroller stores the frequency range of each tuner  318 ,  320 ,  322 ,  324  and thus may electrically connect the proper satellite input to the band translator  336 ,  340 ,  344 ,  348  that translates signals into the tuner&#39;s frequency range. Essentially, each tuner has a dedicated band translator that translates an input signal into a frequency within the frequency band accepted by the tuner. 
         [0072]    For example, presume that tuner  318  accepts frequencies from 950 MHz to 1100 MHz and centered at 1025 MHz, as generally discussed above. Further presume that band translator  336  translates an input signal to have a frequency within this range, as again described above. Accordingly, band translator  336  is dedicated to frequency shifting (e.g., translating) an input signal to a frequency recognized and accepted by the tuner  318 . Because switch  326  is connected both to band translator  336  and each of the satellite inputs  310 ,  312 ,  314 ,  316 , at the direction of the microcontroller  394  the switch  326  may connect any input to the band translator  336 . Thus, once tuner  318  requests a particular channel or program, the microcontroller may instruct the switch  326  to connect the corresponding input to the band translator  336 . The band translator, in turn, translates the input signal&#39;s frequency into one accepted by the tuner  318 . 
         [0073]    Thus, in short, each tuner has a dedicated band translator and each band translator may translate any of the input signals as necessary. The result of this particular embodiment described is that either tuner may request any frequency band from any satellite and yet receive it in the frequency range for which that tuner has already been programmed, thus eliminating the need for television converter device  304  to accept frequency bands as they arrived from the satellite dishes. 
         [0074]    Note that BPF  352 , LMPF  354 , HMPF  356 , HBPF  358  and frequency stacker  390  effectively amount to a multiplexer; that is, more than two bands (“subbands”) are stacked into multiple output frequencies. It should be appreciated that this multiplexer configuration typically requires tuners to have additional spectrum recognition abilities and/or constraints on the use of coaxial cable (which may have shorter allowable runs, additional features to increase bandwidth or may be replaced with other forms of connection) that are within the scope as set forth herein. In such a system, as is evident from  FIGS. 2 and 3 , a band translation switch may support more than two tuners in a single television converter device on a single coaxial cable. As is also evident from the drawings, band translation switches may also be reconfigured so as to support one or more single tuner television converter devices from a single coaxial cable carrying a signal from one or more satellite dishes. 
         [0075]    The control system of switch  302  is also depicted. In operation, control signal detection and transmission interface  392  will detect control signals sent by tuners  318 ,  320 ,  322  and  324  and cooperate with microcontroller  394 . In this embodiment, the control signals sent by tuners  318 ,  320 ,  322  and  324  operate independently. Several control signaling paradigms are possible in various embodiments. Microcontroller  394  has control authority over band translation oscillator control  366 ,  374 ,  382 ,  388  and control signal detection and transmission interface  397 . Interface  397  may be a second control signal detection and transmission interface separate from interface  392 , or in alternative embodiments the two structures may be combined. 
         [0076]    In operation, signals sent from tuners  318 ,  320 ,  322  and  324  are used by microcontroller  394  to control the low band translation oscillators  360 ,  368 ,  376 ,  384  and high band translation oscillators  362 ,  370 ,  378 ,  386 ; by this structure the appropriate satellite signals are sent to LBT  336 , SBT  340 , TBT  344  and HBT  348 . In addition to signals sent from tuners  318 ,  320 ,  322  and  324  to microcontroller  394 , other signals are sent from tuners  318 ,  320 ,  322  and  324  having preambles which indicate that they are to be passed through to the LNBF at the satellite dish. 
         [0077]    In the band translation switches described herein, at least two switching protocols may be used: proprietary 13/18 switching and the DiSEqC 2.0 protocol. In the former technique, television converter devices send proprietary commands to the band translation switch by varying the length and pattern of the 13 volt or 18 volt potential. Based on the commands sent, the band translation switch selects the appropriate signal to send back to the sending television converter devices. Referring once again to  FIG. 3 , the 13/18 polarity may be passed directly by switch  302  to dish/LNBFs  310 ,  312 ,  314 ,  316 , or switch  302  may maintain constant polarity. In one embodiment presently contemplated, the DiSEqC 2.0 protocol is used. The DiSEqC 2.0 protocol, unlike the 13/18 polarity method, allows for bidirectional communication among the five components of the switching system. Television converter devices  304  provide the current to operate switch  302  and the LNBFs located at dish/LNBFs  310 ,  312 ,  314 ,  316 . In other embodiments, switch  302  may be integrated with, included within or housed inside of an LNBF. Under either protocol, television converter devices  304  are capable of independent operation in which the activities of one box do not effect the activities of the other. Under either protocol, tuners are capable of independent operation in which the activities and band selected by one tuner do not effect the activities of the other. 
         [0078]      FIG. 4  depicts a band-stacked low-noise block converter (LNB) embodiment of the method for band translation. In this embodiment, LNB  474  contains band translation block  402  and is connected to satellites  464 ,  466  that receive, respectively, signals from satellites located at 119 degrees west longitude and 110 degrees west longitude. Dish  464  receives signals that are left-hand circular polarized (LHCP) in the frequency band range of 12.2 to 12.7 GHz and right-hand circular polarized (RHCP) in the frequency band range of 12.2 to 12.7 GHz. Likewise, dish  466  also receives signals that are left-hand circular polarized (LHCP) in the frequency band range of 12.2 to 12.7 GHz and right-hand circular polarized (RHCP) in the frequency band range of 12.2 to 12.7 GHz. Alternatively, in another embodiment, dish  464  may receive a single polarity band that comprises a single satellite signal. Various embodiments may employ several satellite orbital locations and radio frequency bands in addition to those described herein. LNB  474  is optionally connected via Aux LNBF Input  468  to a band-stacked LNB  470  input (but may be connected in a variety of different manners in alternative embodiments). 
         [0079]    LNB  474  may include circuitry to maintain signal bands, including amplifiers  460 ,  462 ,  434 ,  432 ,  458 ,  456 ,  428 ,  430 . It should be appreciated that the signal processing circuitry shown is exemplary; alternative configurations may be employed in various embodiments. LNB  474  also includes signal frequency mixers  436  and  438  that are connected via local signal oscillator  446 . Local signal oscillator  446 , operating in this embodiment at a signal frequency of 14.35 GHz, band-stacks the received LHCP signals  448 ,  452  from two independent satellite dishes  464 ,  466  into signals  422 ,  420 . Similarly, LNB  474  also includes signal frequency mixers  442  and  440  that are connected via local signal oscillator  444 . Local signal oscillator  444 , operating in this embodiment at a signal frequency of 11.25 GHz, band-stacks the received RHCP signals  450 ,  454  from two independent satellite dishes  464 ,  466  into signals  424 ,  426 . Frequency stackers  416  and  418  then combine signals  420  and  426  and  424  and  422  as respective pairs. (In the present embodiment, each combiner combines only two bands, although this may vary in other embodiments.) LNB  474  also includes band translation block  402 . Band translation block  402  receives combined signals and processes the requests for specific bands contained within the received signals. Alternative circuit elements and different combinations of existing elements may be used in alternative embodiments, including non-stacked frequency bands. 
         [0080]    Band-stacked output signals from LNB  474  are identified as port  1   404  and port  2   406 . Port  1   404  and port  2   406  may be connected to individual or multiple tuners that may request delivery of specific signal bands. Furthermore, the signals carried on output ports  404  and  406  from LNB  474  may also be connected to other RF processing elements, including but not limited to DiSEqC 2.0/XMT switching protocol detection unit  408 , processing unit  412 , voltage supplies  414  and power management unit  410 . 
         [0081]      FIG. 5  generally depicts a band-stacked LNB embodiment employing an alternate architecture having a single local oscillator instead of two local oscillators, as shown (for example) in the embodiment of  FIG. 4 . The embodiment accepts even and odd signals  500 ,  502 ,  504 ,  506  from a first and second satellite  508 ,  510 . Each signal is fed into a distinct amplifier  512 ,  514 ,  516 ,  518  to generate an amplified signal. It should be noted that each satellite signal has a polarity and is received from a satellite at a particular position, as described above. One of each signal pair is a “low” signal and the other is designated the “high” signal. For example, in the signal pair from satellite  508 , even signal  500  is the high signal and odd signal  502  is the low signal. It should be noted that the particular embodiment shown in  FIG. 5  operates generally with a set top box having two tuners, one tuned to satellite  1 &#39;s broadcast and one tuned to satellite  2 &#39;s broadcast. (Alternatively, one tuner may function as a master and one as a slave as described above, and/or both tuners may be tuned to the same broadcast.) For simplicity&#39;s sake, the signal processing of the high and low signals  500 ,  502  from satellite  1   508  will be discussed. The same operations generally occur on the second satellite&#39;s signals  504 ,  506 . A “high” signal may be, for example, a right-hand circular polarized signal and a “low” signal may be a left-hand circular polarized signal, or vice versa. 
         [0082]    The high signal, once amplified by the amplifier,  512 , is added to a reference signal by the signal mixer  520 . In particular, the high signal is added to (e.g., band-translated with) an 11.25 GHz signal generated by the local oscillator  528 , which may be either a phase-locked loop or digital resonance oscillator. The local oscillator  528  (LO) generates the  11 . 25  GHz signal which is then fed into a splitter  530 . (The splitter  530  may also function to buffer the signal from the LO). As shown in  FIG. 5 , the split signal is transmitted from the splitter  530  to each mixer  520 ,  522 ,  524 ,  526  so that each of the received high and low signals may be band-translated with the 11.25 GHz signal, as generally described above. The output of the mixer  520 , for example, is a band-translated signal having a frequency range generally of 950 to 1450 MHz. Thus, the absolute frequency of the satellite input signal ranges from 12.2 GHz to 12.7 GHz. It should be noted that both the low and high signals are mixed with the 11.25 GHz signal, unlike the operations of the embodiment shown generally in  FIG. 4 . Thus, after passing through mixer  520 , the high signal&#39;s frequency ranges from 950 to 1450 MHz. Similarly, after being operated on by mixer  522 , the low signal&#39;s frequency likewise ranges from 950-1450 MHz. These signals may be amplified by respective amplifiers  532 ,  534 . 
         [0083]    As may be appreciated, the low and high signals have approximately the same frequency ranges after the operations of the mixers  520 ,  522  and amplifiers  532 ,  534 . Band-stacking the low and high signals at this point would result in degradation as the two signals would effectively overlie one another. Accordingly, the high signal, upon exiting amplifier  532 , is band-translated with a 3.1 GHz signal by mixer  540  to yield a signal having a frequency between 1650 and 2150 MHz. 
         [0084]    The 3.1 GHz signal is produced by the band translating circuit  552  and split (and, optionally, buffered) by splitter  546 . The splitter  546  transmits the 3.1 GHz signal to the mixer  540 , which in turn employs the 3.1 GHz signal to translate the high signal in a manner similar to that previously described with respect to  FIGS. 2-4 . The resulting high signal, having been translated twice, is band-stacked with the low signal by diplexer  548 . 
         [0085]    The output of diplexer  548  is a band-stacked signal ranging from 950 to 2150 MHz, combining two separate and unique signals, namely the low and high signals previously discussed. The high signal is spectrally inverted while the low signal remains non-inverted. The two signals are separated by a “guard band” of approximately 200 MHz: one signal ranges across a frequency band of 950 to 1450 MHz and the second, inverted signal ranges across a frequency band of 1650 to 2150 MHz. The separation of the two signals by the guard band, and the functions of the guard band, are generally discussed above. It should be noted that, in certain embodiments, the high band signal may not be spectrally inverted. Any of the embodiments discussed herein may employ a non-inverted high signal. 
         [0086]    The same operations are generally performed on the low and high signals received from the second satellite  510  as are performed on the signals received from the first satellite  508 . 
         [0087]    Band translating circuit  552  accepts the band-stacked signals from combiners  548  and  550  and outputs a first and second stacked output  554 ,  556  as generally described above. Essentially, band translating circuit  552  operates in the same manner as the band translation block  402  of  FIG. 4 . 
         [0088]      FIG. 6  depicts another embodiment of a band-stacking LNBF. The embodiment of  FIG. 6  operates in the same fashion as that of  FIG. 5  with one difference. Instead of translating the high signal received from each satellite  600 ,  602  twice (for example., as shown in  FIG. 5  with respect to first mixer  520  and second mixer  540 ), the high signal is translated only once by mixer  604 . A 14.35 GHz signal is fed into mixer  604  (and, incidentally, mixer  606  for the high signal from the second satellite  602 ) for a single translation operation. The embodiment generates this 14.35 GHz signal by adding a 3.1 GHz reference signal to an 11.25 GHz reference signal. In particular, the band translating circuit  610  produces a 3.1 GHz signal (taken from the local oscillator of the circuit  610 ), which is split and, optionally, buffered by splitter  612 . Splitter  612  transmits this signal to mixers  614  and  616 . 
         [0089]    Mixers  614  and  616  also receive an 11.25 GHz signal from a second splitter  618 , which in turn receives the signal from local oscillator  620 . The operation of local oscillator  620  and splitter  618  mirrors that of local oscillator  528  and splitter  530  of  FIG. 5 . Mixers  614  and  616  then add the two reference signals together to produce the 14.35 GHz output that is fed to mixers  604  and  606 , and ultimately used to translate the high signals from each satellite. 
         [0090]    Amplification, stacking and output of the exemplary LNBF of  FIG. 6  is otherwise the same as the embodiment of  FIG. 5 . 
         [0091]      FIG. 7  depicts yet another embodiment of an LNBF. In general, the embodiment of  FIG. 7  operates in the same manner as the embodiment of  FIG. 5 , except that the 3.1 GHz signal used by mixers  702 ,  704  is generated by a dedicated local oscillator  700  instead of being pulled from band translating circuit  706 . In all other respects, the operation is identical. 
         [0092]      FIG. 8  depicts still another embodiment of an LNBF. Again, the embodiment accepts signal pairs from a first satellite  800  and a second satellite  802 . The embodiment performs the same operations on the signals from the first satellite  800  as described previously with respect to  FIG. 5 . The signals from the second satellite  802 , however, are processed somewhat differently. 
         [0093]    Initially, both the high and low signals are amplified by amplifiers  812  and  814 . Next both the high and low signals are mixed with a 6.2 GHz reference signal by mixers  816 ,  818 . The 6.2 GHz signal is produced by doubling, via a doubler  806 , the 3.1 GHz signal intrinsic to the band translating circuit  804 . The resulting signals are again amplified (by amplifiers  820  and  822 , respectively) before being fed into yet more mixers  824 ,  826 . Mixers  824 ,  826  add the high and low signals to a 10.15 GHz signal outputted by a local oscillator  830 . The local oscillator  830  transmits the 10.15 GHz reference signal to a splitter  832 , which splits it and feeds the split signal to both of the mixers  824 ,  826 . 
         [0094]    The low signal exits mixer  826  and is transmitted to the diplexer  838 . The high signal, however, is transmitted from mixer  824  to mixer  836 . Mixer  836  translates the high signal with a 3.1 GHz reference signal outputted by splitter  834 . Translation has been previously described in this document. Once translated, the high signal is also fed to diplexer  838 . The diplexer  838  band stacks the high and low signals of the second satellite  802  in the manner previously described. Likewise, diplexer  840  band stacks the high and low signals of the first satellite  800 . 
         [0095]    The band translating circuit accepts band-stacked signals from the diplexers  838 ,  840  and translates them, in the manner previously described, to produce stacked outputs  844 ,  846 . These stacked outputs  844 ,  846  are similar to those of prior figures. 
         [0096]      FIG. 9  depicts a band translating embodiment  900  employing non-stacked inputs. Generally, the embodiment receives a first high signal and first low signal. Each of the first high signal  902  and first low signal  904  are mixed with an 11.25 GHz reference signal by first and second mixers  906 ,  908 , respectively. The 11.25 GHz reference signal may be generated, for example, by a local oscillator or dielectric resonator oscillator  910 . 
         [0097]    The outputs of the first and second mixers  912 ,  914  may optionally be amplified and take the form of first and second non-stacked signals. Both of the first and second non-stacked signals occupy a frequency band of approximately 950-1450 MHz. 
         [0098]    Similarly, the embodiment of  FIG. 9  may also receive a second high signal  916  and second low signal  918 . The second high and low signals may be, for example, 17 GHz signals having a right-hand and left-hand polarity, respectively. (In some embodiments, the polarities may be reversed.) The second high and low signals may be mixed with a 16.35 GHz reference signal by third and fourth mixers  920 ,  922 , respectively, to produce third and fourth non-stacked signals  930 ,  932 , each within a 950-1450 MHz frequency band. 
         [0099]    The 16.35 GHz reference signal may be generated in the present embodiment by doubling the output of a 8.175 GHz oscillator  924  via a doubler  926 . 
         [0100]    A band translating circuit  928  accepts the first, second, third and fourth non-stacked signals  912 ,  914 ,  930 ,  932  and operates generally as described above to produce two stacked outputs. Accordingly, it should be understood that certain embodiments may translate signals without band stacking the signals. 
         [0101]    Although the present invention has been described with respect to particular embodiments, apparatuses and processes, it should be understood that these are illustrative rather than limiting. Variations on the embodiments, apparatuses and processes described herein may be created without departing from the spirit or scope of the invention. Further, it should be noted that all frequencies and signals discussed herein are provided by way of example and not limitation. Alternative embodiments may vary frequencies or any other signal characteristic as necessary or desired. It should also be noted that frequency mixing and/or frequency translating, as described herein, are examples of band translating in accordance with this disclosure.