WO2007081733A1

WO2007081733A1 - Apparatus and method for satellite channel selection and translation

Info

Publication number: WO2007081733A1
Application number: PCT/US2007/000145
Authority: WO
Inventors: Rejimon G. Varghese; Barry Jay Weber
Original assignee: Thomson Licensing
Priority date: 2006-01-04
Filing date: 2007-01-04
Publication date: 2007-07-19

Abstract

There is provided a communication circuit (200). In an exemplary embodiment, the communication circuit (200) comprises a circuit (220) that is adapted to receive a terrestrial signal corresponding to a terrestrial frequency spectrum (504) and a satellite signal corresponding to at least one user band (506a, 506b, 506c) and to create an output signal that combines the terrestrial frequency spectrum (504) and the at least one user band (506a, 506b, 506c). An exemplary communication circuit (200) additionally comprises a circuit (300) that is adapted to reposition a satellite frequency spectrum (402, 406, 410, 414) in an unused frequency band of the output signal.

Description

Apparatus and Method for Satellite Channel Selection and Translation

This application claims the benefit under 35 U.S.C.§ 119 of a provisional application 60/756,104 filed in the United States on January 4, 2006.

FIELD OF THE INVENTION

The present disclosure relates generally to an apparatus and method for selecting and translating channels in a receiving structure and more specifically toward a channel router capable of selecting channels as well as an entire band of channels.

BACKGROUND OF THE INVENTION

This section is intended to introduce the reader to various aspects of art which may be related to various aspects of the present invention which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

Channel routers a new class of products emerging in the satellite industry, are capable of taking a single channel (or N unique channel) and remapping it to a new frequency location (or N new frequency locations). Further, with only the addition of switches, the (satellite channel router) SCR can receive inputs from more than one satellite input source, such as inputs from two polarizations or different satellite orbital locations. An SCR allows a satellite operator to target multiple dwelling units (MDU's) with only a single lateral cable connected to each unit or to deploy services to a multi-tuner home gateway with only a single cable from the satellite dish.

Each channel in an SCR has a cost of approximately $5-$7 per translated frequency band. Depending on the type of technology used, the number of translated channels can be purchased in increments of 1 , 2 or 3. However, adding an additional translated channel may not be simple. Often the solution involves the addition of more circuitry, and thus, there may be cases where going from capability of translating 3 channels to capability of translating 4 channels (as an example) could cost an extra $10-$ 14.

Often, the satellite operator requires an 'always-on' channel or an emergency recovery channel that must be available for monitoring purposes independent of the user's channel selections. The recovery channel is often an extra channel from which the satellite operator or local service provider cannot directly recover income and would thus like to have a low cost implementation for providing this channel. Therefore, in order to provide channel expansion possibilities as well as add a dedicated recovery channel to the system, there is a desire to provide a circuit and method for providing an additional channel in an SCR at a relatively low cost. SUMMARY OF THE INVENTION

The disclosed embodiments relate to an apparatus and method for selecting and translating channels in a receiving system. In one embodiment A signal processing circuit includes a circuit for receiving a signal corresponding to a frequency spectrum and providing a signal containing at least one user band and a circuit for repositioning one of the frequency spectrum in a frequency band that is unused by the at least one user band and creating an output signal that combines the signal containing at least one user band with the repositioned frequency spectrum.

In another embodiment, an electronic device includes an automatic level control circuit that is adapted to receive a satellite signal corresponding to at least one user band, a switch and frequency translation circuit that is adapted to receive the satellite signal from the automatic level control circuit, and a circuit that is adapted to reposition a satellite frequency spectrum in an unused frequency band, and a circuit that is adapted to create an output signal that combines the repositioned satellite frequency spectrum and the at least one user band.

In another embodiment, a method includes receiving a signal corresponding to at least one user band, repositioning a frequency spectrum in a frequency band not used by the at least one user band, and creating an output signal that combines the repositioned frequency spectrum and the at least one user band.

Certain aspects commensurate in scope with the disclosed embodiments are set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of certain forms the invention might take and that these aspects are not intended to limit the scope of the invention. Indeed, the invention may encompass a variety of aspects that may not be set forth below.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

Fig. 1 is a diagram showing representative spectrum utilization for a conventional 3 and 4 channel product;

Fig. 2 is a block diagram of a communication circuit in accordance with an exemplary embodiment of the present invention;

Fig. 3 is a block diagram of a frequency shifting circuit in accordance with an exemplary embodiment of the present invention;

Fig. 4 is a diagram showing a representative mapping of LNB inputs to an SCR;

Fig. 5 is a diagram showing a spectrum utilization of one of the outputs of an exemplary embodiment of the present invention; and

Fig. 6 is a flow charting showing an exemplary process of an embodiment of the present invention. DETAILED DESCRIPTION

One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

The following describes a circuit used for receiving and translating satellite signals. Other systems utilized to receive translate other types of signals where the signal input may be supplied by some other means may include very similar structures. Those of ordinary skill in the art will appreciate that the embodiment of the circuits described herein is merely one potential embodiment. As such, in alternate embodiments, the components of the circuit may be rearranged or omitted, or additional components may be added. For example, with minor modifications, the circuits described may be configured to for use in non-satellite video and audio services such as those delivered from a cable network. A satellite channel router (SCR) Is a device used to translate and combine individual channels from different satellite feeds and supply them to a home on one cable. The satellite frequency translator may have a confined structure that may limit its ability to provide additional channels in a cost effective manner. An exemplary embodiment of the present invention provides a low cost addition and method for providing at least one additional channel to the output of the satellite frequency translator device.

An apparatus in accordance with an exemplary embodiment

S of the present invention generates one or more new channels, including one entire band of channels, representing a satellite signal feed, used for program guide and recovery information all conveniently located in a suitable frequency range, from a plurality of satellite signal feeds each delivered to the apparatus on a separate cable. The apparatus provides the new channel(s) on a single cable suitable for delivery into a home that has multiple receivers. An exemplary embodiment of the present invention generates the plurality of new channels based on requests from all of the multiple receivers within a single home. An exemplary apparatus also includes an output containing the new channels and excluding the one entire original band, as well as outputs containing one or more of the original satellite signal feeds. In this manner, the device is capable of supplying multiple homes with multiple levels of service simultaneously. An exemplary apparatus provides a cost effective alternative for supplying a plurality of channels to a single home containing multiple receivers.

An exemplary embodiment of the present invention is directed towards a satellite signal selection and translation device such as an SCR. More specifically an exemplary embodiment of the invention is directed towards an SCR that allows a plurality of unique transponders to be remapped to a specific first frequency space and in addition allows a complete remapping of a second complete group of transponders to a second frequency space. Further, an exemplary embodiment of the invention includes the capability to output a number of combinations of the outputs and also includes a method for controlling the SCR.

Fig. 1 is a diagram showing representative spectrum utilization for a conventional three and four channel product. The diagram is generally referred to by the reference number 100. The diagram comprises a graph 102, in which the x-axis represents frequency and the y-axis represents signal magnitude. The graph 102 comprises a terrestrial frequency spectrum 104 and three additional frequency bands 106a, 106b and 106c. The graph 102 represents an output spectrum of a conventional SCR arrangement using one 3-channel frequency translator integrated circuit device. The terrestrial frequency spectrum 104, which is associated with the terrestrial broadcast television spectrum, can be combined in from a separate input, as described below.

Fig. 1 further includes a graph 108, in which the x-axis represents frequency and the y-axis represents signal magnitude. The graph 108 comprises a terrestrial frequency spectrum 110 and four additional frequency bands 112a, 112b, 112c and 112d. The graph 108 represents an output spectrum of a conventional SCR arrangement using two numbers of a 2-channel frequency translator integrated circuit device. The terrestrial frequency spectrum 110, which is associated with the terrestrial broadcast television spectrum, can be combined in from a separate input, as described below.

Fig. 2 represents an overall block diagram of a communication circuit in accordance with an exemplary embodiment of the present invention. The communication circuit is generally referred to by the reference number 200. Four inputs are shown as delivered from two separate satellite sources shown as low noise block converters (LNBs) 201a, 201b. An additional input from a terrestrial antenna 203 is shown, for separate combining in with the satellite signals. The satellite inputs are first delivered to an ESD protection and automatic level control circuit 202, which also receives power and control signals from an LNB power and control block 204. From the ESD protection and automatic level control circuit 202, the satellite signals are provided to one or more switch and frequency translation integrated circuit(s) 206. The switch and frequency translation circuit(s) 206 provides the selection for determining the signal required (chosen for viewing) by a system user. The output of the switch and frequency translation circuit(s) 206 is one or more user bands corresponding to satellite signals received from the LNBs 201a, 201b.

In the exemplary embodiment illustrated in Fig. 2, user band outputs from the switch and frequency translation circuit(s) 206 are delivered to a diplexer 208, a high pass filter 210, a mixer 214 (that receives a frequency input from a frequency source 216) and a 2- way combiner and diplexer 220. The mixer 214 delivers an output signal to a high pass filter 218, which provides an input to the 2- way combiner and diplexer 220. The switch and frequency translation circuit(s) 206 is(are) controlled by a microcontroller and communication circuit 212.

The communication circuit 200 typically has several outputs including a combined translated output (or SCR output) (identified as SCR OUT1 in Fig. 2), a separate translated output (identified as SCR OUT2 in Fig. 2), and a selected untranslated signal set output (identified as Legacyi in Fig. 2). Each of these outputs may be used either directly or combined with further functions and then supplied as signals for various uses in the distribution system.

As shown in Fig. 2, outputs are provided for an SCR output with additional terrestrial signals (SCR OUT1), a legacy output (Legacyi), and an SCR output with added channel capability combined with terrestrial signals (SCR OUT2). Also included is a separate multiplex switch, identified as RF switch 222, connected to each of the satellite signal set inputs for providing two more legacy outputs (Legacy2 and Legacy3).

Fig. 3 is a block diagram of a frequency shifting circuit in accordance with an exemplary embodiment of the present invention. The frequency shifting circuit is generally referred to by the reference number 300. The frequency shifting circuit 300 may be implemented as a portion of the 2-way combiner and diplexer 220 (Fig. 2), and may be used to create and reposition a replicated satellite frequency spectrum corresponding to signals received by one of the LNBs 201a, 201b.

The exemplary embodiment of the present invention shown in Fig. 3 utilizes a frequency up conversion technique and places the signals from any one LNB at a vacant or unused space of the band in the output signal. One of ordinary skill in the art will appreciate that suitable software changes may need to be made to the tuning algorithm to select the transponders from this band.

The frequency shifting circuit 300 includes a crystal oscillator 302, which provides a frequency input to a phase locked loop (PLL) synthesizer 304. The PLL synthesizer 304 is connected to a voltage controlled oscillator 310, which provides an output to a double balanced mixer 308. The double balanced mixer 308 is adapted to receive a selected LNB band, such as from one of the LNBs 201a and 2021b (Rg. 2), and to provide a shifted band output. A bypass switch 306 is adapted to bypass the double balanced mixer 308 if no frequency shifting is desired for a particular LNB input.

Including the additional circuitry shown in Fig. 3 to a control circuit such as the control circuit 200 (Fig. 2) allows an additional transponder to be received by any of the satellite receivers in the SCR network at a relatively low cost. An exemplary embodiment of the present invention exploits the availability of otherwise unused bandwidth in the absence of future SCR product updates that mandate the usage of the unused bandwidth.

Fig. 4 is a diagram showing a representative mapping of LNB inputs to an SCR. The diagram is generally referred to by the reference number 400. Moreover, Fig. 4 shows a representation of the signals present for each of the satellite signal sets provided as inputs to the SCR. Each of the signals represents a different signal set from a satellite. For instance, the signal sets could represent the right and left hand polarization signals from two satellites located in different orbital slots in space. The diagram 400 includes a first graph 402 representative of a satellite frequency spectrum, having an x-axis corresponding to frequency and a y-axis corresponding to signal magnitude. The satellite frequency spectrum 402 comprises a plurality of satellite frequency bands 404 corresponding to a signal received by one of the LNBs 201a, 201b (Fig. 2). A second graph 406 representative of a satellite frequency spectrum has an x-axis corresponding to frequency and a y-axis corresponding to signal magnitude. The satellite frequency spectrum 406 comprises a plurality of satellite frequency bands 408 corresponding to a signal received by one of the LNBs 201a, 201b (Fig. 2). A third graph 410 representative of a satellite frequency spectrum has an x-axis corresponding to frequency and a y-axis corresponding to signal magnitude. The satellite frequency spectrum 410 comprises a plurality of satellite frequency bands 412 corresponding to a signal received by one of the LNBs 201a, 201 b (Fig. 2). A fourth graph 414 representative of a satellite frequency spectrum has an x-axis corresponding to frequency and a y-axis corresponding to signal magnitude. The satellite frequency spectrum 414 comprises a plurality of satellite frequency bands 416 corresponding to a signal received by one of the LNBs 201a, 201b (Fig. 2).

Fig. 5 is a diagram showing a spectrum utilization of one of the outputs a frequency spectrum in accordance with an exemplary embodiment of the present invention. The diagram is generally referred to by the reference number 500. Moreover, Fig. 5 shows a representative frequency spectrum for the output containing the satellite frequency spectra, the added channels, and the terrestrial spectrum. The diagram 500 comprises a graph 502 having an x-axis corresponding to frequency and a y-axis corresponding to signal magnitude. The graph 502 further comprises a terrestrial frequency spectrum 504, three additional user bands (506a, 506b and 506c) produced by the switch and frequency translation circuit 206 (Fig. 2), and an additional satellite frequency band 508, also known as an extra band, added by a circuit such as the frequency shifting circuit 300 (Fig. 3). Any one of the satellite frequency bands 402, 406, 410 or 414 (Fig. 4) may be replicated and repositioned in an unused portion of the spectrum shown in Fig. 5. In the exemplary embodiment shown in Fig. 5, one of the satellite frequency bands 402, 406, 410 or 414 (Fig. 4) is shown as the additional satellite frequency band or extra band 508.

In addition to the figures shown, a method for controlling the SCR with an exemplary embodiment of the present invention is described herewith. A microcontroller 212 residing within an SCR typically provides control of the operation of the SCR after receiving control messages from client devices connected to the output of the SCR. The control messages are typically sent over the RF cable from one or more set top boxes using some type of signaling in the lower parts of the frequency band. For instance, the control messages may use digital satellite equipment control (DiSEqC) or proprietary two level frequency shift keying (2-FSK).

Fig. 6 illustrates a process 600 for controlling a device such as an SCR. At step 610, the process is initialized. Initialization may include initial power on of devices including the SCR or a set top box. Initialization may also include resetting the devices through either a hardware or software reset function. At 620, the capability of the SCR is determined. The discovery of the capability of the SCR involves determining if the SCR contains circuits for shifting an incoming frequency spectrum to create an extra band or whether the circuits for shifting a frequency spectrum are currently available for adjustment. For example, a satellite service provider may require that a particular frequency spectrum always be selected and used as the extra band.

In order to facilitate discovery of capability in step 620, several interfaces between a set top box and SCR may be possible. In one embodiment, the set top box through its current switch system utilizes a back channel that is capable of sending back a binary response (0 or 1) through the primary satellite RF path. Discovery of the SCR device capability may be implemented with a command that returns a 0 if the device does not have extra band capability and a 1 if it does have extra band capability. In a second embodiment, specific commands are generated using a control interface such as DiSEqC.

If capability, as determined at step 620 is not available, the process continues without further processing of commands associated with the extra band capability. At step 630, commands are received in order to tune channels and create user bands. The channel commands may be provided from multiple set top boxes, and each set top box may control, based on the commands, a specific portion of the SCR. In one embodiment, modified DiSEqC can be used to control channel changes in the switch through the use of commands that send up a desired user band (output frequency), desired satellite frequency and desired satellite source. If capability, as determined at step 620 is available, the process continues by allowing further processing of commands associated with the extra band capability. At step 635, commands are received in order to tune channels and create user bands. The channel commands are processed in a manner similar to that described in step 635. In addition, at step 640, information associated with generating an extra band, based on the commands, provided is processed to determine the extra band. The extra band determination may be done based on processing of additional information provided in the channel commands. The extra band determination may also be done based information provided separately from the channel commands. In one embodiment, the following information is provided in order to generate the extra band:

(a)Source satellite (1 of 8) (b)Half quadrant (1 of 2)

The source satellite is one of the inputs provided from LNBs 201a and 201b. The source satellite is typically already provisioned for based on channel commands for generating the user bands, so the only remaining selection is either the lower or upper half quadrant. In order to not add any new bits to the message, two states that will not be used in the normal operation of DiSEqC may be used to send the extra band information. The SCR may use the following algorithm to determine the extra band:

If (USER_BAND[2:0] == 7) && (FREQUENCY == 0) then EXTRA_BAND = LOWER ELSE IF (USER_BAND[2:0] == 7) && FREQUENCY[9:0] == 1 ) then EXTRA_BAND = UPPER

ELSE EXTRA_BAND does not change

The advantage of using unused portions of the DiSEqC command structure is that the format of the channel change does not need to be altered in the set top box.

In a second embodiment, specific dedicated commands may be created for controlling the extra band content. These commands may contain the following information:

Input source (3 bits)

Upper or lower quadrant (2 bits)

After the user bands and the extra band are determined at step 640, step 650 determines whether the currently determined extra band is already selected. If at step 650, the new extra band determined in step 640 is not already selected, then at step 670, the spectrum for the extra band is selected and repositioned. In one embodiment, the satellite frequency spectrum is shifted to an unused portion of frequency spectrum. All of the switching and software interaction is handled by the switch chip. The mixing and band shifting, such as the band shifting is performed by the frequency shifting circuit 300 (Fig. 3),

After determining the user bands, either at step 630 or step 640, the user bands, at step 655, are generated. The user bands are generated using the circuitry described previously within the SCR including switch and frequency translation integrated circuit(s) 206. After the user bands are generated, at step 675, the user bands are received in a different portion of the SCR for eventually combining and output.

Finally at step 680, an output signal is created in 2-way combiner and diplexer 220. The output signal is created by combining either the current extra band if there was no change necessary as determined at step 650, or the repositioned spectrum for the new extra band from step 670, with the with the received user bands from step 675.

In addition, if a terrestrial signal has been processed and is available, it may be combined at step 680 as well. Also, the commands provided to the SCR may include other control features available in the SCR such as outputting a legacy satellite spectrum signal.

While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.

Claims

What is claimed is:

1. A signal processing circuit (200), comprising: a circuit (220) for receiving a signal corresponding to a frequency spectrum (402, 406, 410, 414) and providing a signal containing at least one user band; and a circuit (300) for repositioning one of the frequency spectrum (402, 406, 410, 414) in a frequency band that is unused by the at least one user band and creating an output signal that combines the signal containing at least one user band (506a, 506b, 506c) with the repositioned frequency spectrum (402, 406, 410, 414).

2. The signal processing circuit (200) recited in claim 1 comprising a circuit (220) for receiving a terrestrial signal corresponding to a terrestrial frequency spectrum (504) and combining the terrestrial frequency spectrum with the output signal.

3. The signal processing circuit (200) recited in claim 2, comprising an antenna (203) that receives the terrestrial signal.

4. The signal processing circuit (200) wherein the received signal is a satellite signal and the first spectrum is a satellite spectrum.

5. The signal processing circuit (200) recited in claim 1 , comprising an LNB (201a, 201b) that receives the satellite signal.

6. The signal processing circuit (200) recited in claim 1 , comprising an RF switch (222) that receives the satellite signal and to produce a legacy output based thereon.

7. The signal processing circuit (200) recited in claim 1, wherein the circuit (300) comprises a double balanced mixer (308).

8. The signal processing circuit (200) recited in claim 5, wherein the circuit (300) comprises a bypass switch (306) for bypassing the double balanced mixer (308).

9. The signal processing circuit (200) recited in claim 1 , wherein the circuit (220) receives the at least one user band (506a, 506b, 506c) from a switch and frequency translation circuit (206).

10. The signal processing circuit (200) recited in claim 1 , wherein the communication circuit (200) comprises a portion of a satellite channel router (SCR).

11. An electronic device (200), comprising: an automatic level control circuit (202) that is adapted to receive a satellite signal corresponding to at least one user band (506a, 506b, 506c); a switch and frequency translation circuit (206) that is adapted to receive the satellite signal from the automatic level control circuit; a circuit (300) that is adapted to reposition a satellite frequency spectrum (402, 406, 410, 414) in an unused frequency band; and a circuit (220) that is adapted to create an output signal that combines the repositioned satellite frequency spectrum and the at least one user band (506a, 506b, 506c).

12. The electronic device (200) recited in claim 11 comprising a circuit (220) for receiving a terrestrial signal corresponding to a terrestrial frequency spectrum (504) and combining the terrestrial frequency spectrum with the output signal.

13. The electronic device (200) recited in claim 12, comprising an antenna (203) for receiving the terrestrial signal.

14. The electronic device (200) recited in claim 11 , comprising a low noise block converter (201a, 201b) for receiving the satellite signal.

15. The electronic device (200) recited in claim 11 , comprising an RF switch (222) for receiving the satellite signal and to produce a legacy output based thereon.

16. The electronic device (200) recited in claim 11, wherein the circuit (300) comprises a double balanced mixer (308).

17. The electronic device (200) recited in claim 16, wherein the circuit (300) comprises a bypass switch (306) for bypassing the double balanced mixer (308).

18. The electronic device (200) recited in claim 11, wherein the circuit (220) receives the at least one user band (506a, 506b, 506c) from a switch and frequency translation circuit (206).

19. The electronic device (200) recited in claim 11 , wherein the communication circuit (200) comprises a portion of a satellite channel router (SCR).

20. A method, comprising: receiving (675) a signal corresponding to at least one user band; repositioning (670) a frequency spectrum (402, 406, 410, 414) in a frequency band not used by the at least one user band (506a, 506b, 506c); and creating (680) an output signal that combines the repositioned frequency spectrum and the at least one user band (506a, 506b, 506c).

21. The method recited in claim 20, wherein the frequency spectrum is a satellite frequency spectrum.

22. The method recited in claim 20, comprising producing a legacy output based on the signal.

23. The method recited in claim 20, comprising shifting (670) a frequency of the satellite frequency spectrum (404, 406, 410, 414) to the unused frequency band of the output signal.

24. The method recited in claim 20, comprising: receiving a terrestrial signal corresponding to a terrestrial frequency spectrum; and combining the received terrestrial spectrum with the output signal.

25. An apparatus, comprising: means for receiving (220) a satellite signal corresponding to at least one user band; means for repositioning (300) a satellite frequency spectrum (402, 406, 410, 414) in an extra band; and means for creating (220) an output signal that combines the extra band and the at least one user band (506a, 506b, 506c).