System and method for multiple access control in satellite communications system
First Claim
1. In a satellite communications system, a method of accessing channels comprising:
- receiving a broadband signal occupying a predetermined portion of the electromagnetic spectrum and broadcast by a satellite to include a plurality of downlink channels;
identifying a portion of said spectrum of said broadband signal in which power is below a predetermined threshold;
translating said portion of said spectrum of said broadband signal in which power is below said predetermined threshold into an identity of an uplink channel; and
transmitting a communication to said satellite using said uplink channel identified in said translating activity.
2 Assignments
0 Petitions
Accused Products
Abstract
A satellite communications system (10) includes a hub (14), a satellite (32), and any number of remote terminals (16). Each remote terminal (16) includes a remote receiver (38), a monitor (40), and a network access controller (42). Each remote receiver (38) is configured to receive and down convert the system'"'"'s entire spectrum of interest from which channels are accessed by the remote terminals (16). The monitors (40) independently perform FFT processes over this entire spectrum, but at a low frequency resolution which is no higher than needed to distinguish channels. Based on these spectral analyses, uplink/inbound channels are independently selected by the network access controllers (42) at each remote terminal (16). Remote terminals (16) immediately transmit data to the hub (14) as soon as they select an uplink/inbound channel.
41 Citations
20 Claims
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1. In a satellite communications system, a method of accessing channels comprising:
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receiving a broadband signal occupying a predetermined portion of the electromagnetic spectrum and broadcast by a satellite to include a plurality of downlink channels; identifying a portion of said spectrum of said broadband signal in which power is below a predetermined threshold; translating said portion of said spectrum of said broadband signal in which power is below said predetermined threshold into an identity of an uplink channel; and transmitting a communication to said satellite using said uplink channel identified in said translating activity. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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13. A satellite communications system comprising:
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a communications satellite positioned in an orbit about the Earth; and a plurality of remote terminals wherein each of said remote terminals is configured to independently receive a broadband signal occupying a predetermined portion of the electromagnetic spectrum, to identify a portion of said spectrum of said broadband signal in which power is below a predetermined threshold, to translate said portion of said spectrum of said broadband signal in which power is below said predetermined threshold into an identity of an uplink channel, and to transmit to said satellite using said uplink channel; wherein each of said remote terminals includes a receiver and a monitor, each receiver is configured to sample said broadband signal to form a block of samples, and each monitor is configured to perform a Fourier transform on said block of samples. - View Dependent Claims (14, 15, 17)
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16. A satellite communications system comprising:
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a communications satellite positioned in an orbit about the Earth, wherein said satellite includes a plurality of transponders wherein each transponder transmits in a portion of the electromagnetic spectrum defined by a transponder bandwidth; and a plurality of remote terminals wherein each of said remote terminals is configured to independently receive a broadband signal occupying a predetermined portion of the electromagnetic spectrum, to identify a portion of said spectrum of said broadband signal in which power is below a predetermined threshold, to translate said portion of said spectrum of said broadband signal in which power is below said predetermined threshold into an identity of an uplink channel, and to transmit a communication to said satellite using said uplink channel; wherein, each of said remote terminals includes a receiver configured to receive an electromagnetic signal having a bandwidth greater than said transponder bandwidth; and wherein, each of said remote terminals includes a monitor coupled to said receiver and configured to repetitively identify portions of said spectrum of said broadband signal in which power is below said predetermined threshold, with repetitions occurring at a rate of more than 200 times per second. - View Dependent Claims (20)
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18. A communications system comprising:
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a terrestrially-located hub terminal; a communications satellite positioned in a substantially geosynchronous orbit about the Earth, said communications satellite transmitting over a portion of an electromagnetic spectrum that spans a bandwidth of more than 200 MHz and is divided into a plurality of downlink channels; fewer than 1000 terrestrially-located remote terminals in communication with said hub terminal through said communications satellite, wherein each remote terminal comprises; a receiver configured to receive an electromagnetic signal having a bandwidth of more than 200 MHz and to sample said electromagnetic signal to form a block of samples; a monitor coupled to said receiver and configured to identify portions of said bandwidth in which power is below a predetermined threshold; a network access controller coupled to said monitor and configured to translate said portions of said bandwidth into identities of corresponding uplink channels; and a transmitter coupled to said network access controller and configured to be tuned to and transmit over one of said uplink channels. - View Dependent Claims (19)
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Specification