Satellite communication may include satellites that transmit data in a broad beam that transmit data over a large geographic area or narrow beams that transmit data over a localized area. For example, as shown in
A method for receiving both regional data and local data from one or more satellites and/or terrestrial repeaters at a satellite subscriber terminal is provided according to one embodiment. The method may comprise receiving the regional data during a first time slot and receiving the local data during a second time slot, where the local data is multiplexed in one of a plurality of frequency bands. The method may further include demultiplexing the local data. The local data may be transmitted in a spot beam and the regional data may be transmitted in a broad beam. Each of the plurality of frequency bands may include broadcast and local data for a specific locality and the data may be transmitted within a spot beam covering the specific locality. The regional data may be received within a first frequency band and the plurality of frequency bands may include frequency sub-bands within the first frequency band. The local data may be multiplexed using frequency division multiple access techniques. The local data may also be multiplexed in a frequency reuse pattern similar to cellular networks.
A satellite subscriber terminal configured to receive both regional data and local data from one or more satellites or terrestrial repeaters is provided according to another embodiment. The subscriber terminal may include at least a receiver and a demultiplexer. The receiver may be configured to receive regional data within a first time slot and local data within a second time slot and the local data may be multiplexed within one of a plurality of frequency bands. The demultiplexer may be configured to demultiplex the local data from the plurality of frequency bands. The demultiplexer may comprise a processor configured to perform a demultiplexing function. The regional data may be transmitted within a first frequency band and the plurality of frequency bands may be frequency sub-bands within the first frequency band. The local data may be multiplexed using frequency division multiple access techniques.
A satellite subscriber terminal configured to receive both regional data and local data from one or more satellites and/or terrestrial repeaters is provided according to another embodiment. The subscriber terminal may include means for receiving regional data from a first satellite within a first time slot and local data from a second satellite within a second time slot and means for demultiplexing the local data from the plurality of frequency bands. The local data may be multiplexed within one of a plurality of frequency bands. The first and second satellite may be the same satellite. The local data may be multiplexed within the second timeslot, for example, using frequency division multiple access techniques.
A method for transmitting both regional data and local data to a plurality of subscriber terminals is also provided according to another embodiment. The method may include any of the following steps in any order or combination: 1) receiving regional data from a first gateway; 2) receiving a plurality of local data from a second gateway; 3) multiplexing the plurality of local data, wherein each of the plurality of local data is multiplexed into a sub-frequency band within a first frequency band; 4) transmitting at least a portion of the regional data in a first time slot over the first frequency band; and 5) transmitting at least a portion of the multiplexed local data in a second time slot over the first frequency band. Each of the plurality of local data may be transmitted in a localized spot beam and the regional data may be transmitted in a broad beam. The first gateway and the second gateway may be the same gateway. The plurality of local data may be multiplexed using frequency division multiple access techniques.
A satellite configured to transmit data to a plurality of subscriber terminals over a single wide beam and a plurality of narrow beams is also provided according to another embodiment. The satellite may include a first antenna configured to transmit regional data to each of the plurality of subscriber terminals over a single wide beam and a second antenna configured to transmit a plurality of sets of local data to the plurality of subscriber terminals over a plurality of narrow beams. Each narrow beam may transmit the sets of local data to a subset of the plurality of subscriber terminals. The first antenna and the second antenna may be the same antenna. The regional data may be transmitted over the first antenna in a first time slot and the plurality of sets of local data may be transmitted over the second antenna in a second time slot. The satellite may be configured to transmit each set of local data over separate narrow beams. The plurality of narrow beams may comprise multi-color frequency reuse beam patterns. The regional data may be transmitted within a first frequency band and each set of local data is transmitted within a sub frequency band that is a subset of the first frequency band.
A single satellite subscriber terminal that receives data from both a broad beam and a narrow beam is disclosed. The data contained in the broad beam and the narrow beam may be multiplexed using, for example, time division multiple access (TDM), frequency-division multiplexing (FDM), a combination of the two, or a similar multiplexing scheme. The satellite or satellites may multiplex more than one narrow beam with at least one broad beam. The data contained in the broad beam and the narrow beam may be transmitted from the same source or from different sources. The satellite subscriber terminal receives both the broad beam and the narrow beam through the same receiver.
A satellite communication system that transmits data in a broad beam and plurality of narrow beams that are multiplexed using hybrid time-division and frequency-division multiplexing. A plurality of narrow beams may be multiplexed using FDM. The frequency-division multiplexed plurality of narrow beams may be time-division multiplexed with a broad beam.
Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating various embodiments, are intended for purposes of illustration only and are not intended to necessarily limit the scope of the disclosure.
The ensuing description provides preferred exemplary embodiment(s) only and is not intended to limit the scope, applicability or configuration of the disclosure. Rather, the ensuing description of the preferred exemplary embodiment(s) will provide those skilled in the art with an enabling description for implementing a preferred exemplary embodiment. It should be understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope as set forth in the appended claims.
Referring initially to
The satellite 105 could perform switching or be a bent-pipe. Information bi-directionally passes through the satellite 105. The satellite 105 could use antennas or phased arrays when communicating. The communication data may be focused into narrow beams that are focused on a localized geographic area; for example, a large metropolitan area. Similarly, the communication data may be focused into broad beams that cover large geographic areas, for example, the continental US (CONUS). The data may also be communicated using both narrow beams and broad beams.
As will be discussed in more detail, the service signal 150 from the satellite 105 may be comprised of a regional component that is sent to all subscriber terminals within a broad beam and a plurality of local or narrow beam data that may be transmitted only to subscriber terminals 130 within a specific localized geography covered by the narrow beam. For example, narrow beams may be directed toward a specific geographic locality. The data within the broad and narrow beams may be sent using a modulation scheme such as, for example, TDM, FDM, a combination of the two or a similar multiplexing scheme. The data within the broad and narrow beams may use the same carrier frequency and/or frequency band. A single receiver at the subscriber terminal may receive data from both broad beams and narrow beams using a single antenna.
The subscriber terminals 130 in this embodiment may be bi-directionally coupled to the satellite 105 to provide connectivity with the network 120. Each subscriber terminal 130 can receive information through the downlink signal 150 from the satellite 105, and transmitted information may be sent through a return service 145. Each subscriber terminal 130 may to send information to the satellite 105 and ultimately the gateway 115 through a return service 145.
Satellite subscriber terminals may have multiple antennas coupled with a single receiver. The subscriber terminal 130 can be in a fixed or nomadic location, or can be mobile. In this embodiment, the subscriber terminal 130 interacts with a single transceiver in the satellite 105. Other embodiments could allow the subscriber terminal 130 to interact with multiple transceivers that may communicate with orbital or non-orbital assets (e.g., air, ground or sea based). Some embodiments of the subscriber terminal 130 allow switching between these modes.
The network 120 may be any type of network and can include, for example, the Internet, an IP network, an intranet, a wide-area network (“WAN”), a local-area network (“LAN”), a virtual private network, the Public Switched Telephone Network (“PSTN”), a cluster of computers, and/or any other type of network supporting data communication between devices described herein, in different embodiments. A network 120 may include both wired and wireless connections, including optical links. Many other examples are possible and apparent to those skilled in the art in light of this disclosure. As illustrated in a number of embodiments, the network may connect the gateway 115 with other gateways (not pictured), which are also in communication with the satellite 105.
Referring next to
With reference to
Referring to
Turning now to
The signal may be received at a single antenna 255 and radio 260 of a satellite subscriber terminal 200. The signals may be demultiplexed into a broad beam data 270 and a narrow beam data 275 with a demultiplexer 265. The broad and narrow beam data may be buffered. In other embodiments, only one set of narrow beam data is received at the satellite subscriber terminal. The regional data may be transmitted over a first bandwidth in one timeslot, the local data may be transmitted over a sub-band within the first bandwidth in another timeslot. The transmitter may send control information to the receiver such as timeslot information, data segment lengths, sub-band information, number of segments, error control information, etc.
Each antenna 230, 255 may be made up of one or more individual antenna elements. Each antenna may be a fixed or phased array of, for example, monopoles or reflectors, or any other type or configuration known in the art. A variety of types of beamforming may be used by adaptively controlling the processing of patterns, orientations, and polarizations to improve performance, as discussed below or known in the art.
In one embodiment, various techniques are used (e.g., by the systems 100, 200 of
As used throughout this application data that is transmitted over a narrow beam is referred to as narrow beam data. Local data may comprise, for example, multicast video, unicast IP data, localized data, local television data, internet data, interactive data, voice over IP, etc. Also, as used throughout this application data transmitted over a broad beam is referred to as a broad beam data. Regional data may include, for example, broadcast television information, multicast video, unicast IP data, etc.
The broad beam data 215 may also be transmitted during a dedicated timeslot as directed by the scheduler 222, prepared by the radio 225-b and transmitted over a large geographical region through antenna 230-b. The broad beam data may be transmitted using portions of the same frequency as the narrow beam data 210. Timeslots may be used to transmit narrow beam data and broad beam data to ensure the data does not overlap.
The subscriber terminal 250, according to this embodiment, receives the combined signal at an antenna 255 and processes the signal through a radio 260. The data may then be buffered at block 280. The narrow beam data and broad beam data may be combined 285. The narrow beam data may be buffered separately from the broad beam data.
Localized signals 210 may include, for example, local broadcasting information for satellite radio or satellite television. The narrow beam data may be transmitted only to the localities associated with the local broadcasting information using a narrow beam from the transmitter. Broad beam data, for example, may include national radio or television programming. For example, a national television program may be broadcast nationwide to consumers with a satellite television receiver. Local commercials may be transmitted as narrow beam data only to specific localities, so that consumers in different geographic locations will view the same television program and view different local commercials. Local information, for example, Amber Alerts, weather information, or sports scores, may also be transmitted with the narrow beam data. Furthermore, narrow beam data may also include Internet data. Broad beam data and narrow beam data may be transmitted with a single carrier frequency using TDM. In another embodiment, the broad beam data and the narrow beam data may be transmitted within the same frequency band using FDM. In another embodiment, local programming, such as local news, sports, or specialty shows may be transmitted as narrow beam data.
The satellite subscriber terminal may also include an amplifier and/or an analog to digital converter. In one embodiment the demultiplexer is placed after the amplifier and before a converter.
The above descriptions related to
Embodiments may be used in a terrestrial radio access network (T-RAN), a satellite radio access network (S-RAN) or a combination of the two. Furthermore, embodiments may communicate television programming and/or network data.
Returning to
As discussed in regard to
If either the second or third configuration is used, then a terrestrial repeater 123 shall synchronize with the downstream frame structure so that it transmits in either the wide beam region (if so desired) or in one or more of the spot beam transmission regions. Each repeater could be used to transmit complementary information in either the wide beam and/or one or more narrow beam time/frequency regions.
Also, it is noted that the embodiments may be described as a process which is depicted as a flowchart, a flow diagram, a data flow diagram, a structure diagram, or a block diagram. Although a flowchart may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be rearranged. A process is terminated when its operations are completed, but could have additional steps not included in the figure. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc. When a process corresponds to a function, its termination corresponds to a return of the function to the calling function or the main function.
Furthermore, embodiments may be implemented by hardware, software, scripting languages, firmware, middleware, microcode, hardware description languages, and/or any combination thereof. When implemented in software, firmware, middleware, scripting language, and/or microcode, the program code or code segments to perform the necessary tasks may be stored in a machine-readable medium such as a storage medium. A code segment or machine-executable instruction may represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a script, a class, or any combination of instructions, data structures, and/or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, and/or memory contents. Information, arguments, parameters, data, etc. may be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc.
For a firmware and/or software implementation, the methodologies may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. Any machine-readable medium tangibly embodying instructions may be used in implementing the methodologies described herein. For example, software codes may be stored in a memory. Memory may be implemented within the processor or external to the processor. As used herein, the term “memory” refers to any type of long term, short term, volatile, nonvolatile, or other storage medium and is not to be limited to any particular type of memory or number of memories, or type of media upon which memory is stored.
Moreover, as disclosed herein, the term “storage medium” may represent one or more memories for storing data, including read only memory (ROM), random access memory (RAM), magnetic RAM, core memory, magnetic disk storage mediums, optical storage mediums, flash memory devices and/or other machine readable mediums for storing information. The term “machine-readable medium” includes, but is not limited to portable or fixed storage devices, optical storage devices, wireless channels, and/or various other storage mediums capable of storing that contain or carry instruction(s) and/or data.
In the appended figures, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.
While the principles of the disclosure have been described above in connection with specific apparatuses and methods, it is to be clearly understood that this description is made only by way of example and not as limitation on the scope of the disclosure.
This application is a non-provisional and claims the benefit of U.S. Provisional Patent Application No. 60/895,512, filed Mar. 19, 2007, entitled “Multiple Input Receiver In Satellite Communication System,” which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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60895512 | Mar 2007 | US |