Plural beam reduction of multipath reflections
First Claim
1. A communication system including an antenna system to be carried by a vehicle traveling above the earth'"'"'s surface for communication with plural receivers located distant from each other on the earth'"'"'s surface, the antenna system comprising:
- means for generating a signal to be transmitted from said vehicle to said receivers;
carrier means for providing a plurality of carriers at a plurality of respective carrier frequencies;
modulation means for modulating each of said carriers with said signal to provide a set of modulated carriers;
beam-forming means for generating a plurality of beams, said beams being directed in different directions from said vehicle to said receivers allowing individual ones of said receivers to be illuminated by different individual ones of said beams;
transmission means for transmitting each of said modulated carriers via at least one of said beams, a carrier frequency of at least one of said beams being different from a carrier frequency of another of said beams;
wherein, in said communication system, each of said receivers has means for tuning the receiver to one of said carrier frequencies, respective ones of a plurality of said receivers being tuned to respective ones of said carrier frequencies to enable receptions of said signal at different locations via different carrier frequencies for reduction of multipath interference;
said beam-forming means includes an array of antenna elements comprising a central antenna element surrounded by a set of peripheral antenna elements, respective ones of said antenna elements providing respective ones of said beams;
said carrier means is operative to adjust a value of an individual one of said carrier frequencies;
said communication system further comprises a communication link between an individual one of said receivers and said vehicle for directing said carrier means to adjust a value of a carrier frequency;
said central antenna element is operative at a first carrier frequency, and said set of peripheral antenna elements is operative at a set of carrier frequencies different from said first carrier frequency;
on the earth'"'"'s surface, a portion of one of said beams overlaps a portion of another of said beams to form an overlap region; and
in each of said receivers, each of said tuning means has a signal strength selector for selecting a strongest of a plurality of said modulated carriers, and upon illumination of an individual one of said receivers within said overlap region, said signal strength selector enables said tuning means to tune to a modulated carrier having a largest signal strength.
2 Assignments
0 Petitions
Accused Products
Abstract
A method and system provides for reduced interference from multipath reflections at the earth'"'"'s surface during a communication between a vehicle traveling above the earth'"'"'s surface and receivers at plural ground stations located distantly from each other on the earth'"'"'s surface. Plural antenna elements are carried by the vehicle and oriented in different direction to provide electromagnetic beams at different orientations and different carrier frequencies. This provides wide area coverage while allowing a receiver to be tuned to a signal received from one antenna element while attenuating a multipath reflection at a carrier frequency utilized by another of the receivers.
11 Citations
14 Claims
-
1. A communication system including an antenna system to be carried by a vehicle traveling above the earth'"'"'s surface for communication with plural receivers located distant from each other on the earth'"'"'s surface, the antenna system comprising:
-
means for generating a signal to be transmitted from said vehicle to said receivers; carrier means for providing a plurality of carriers at a plurality of respective carrier frequencies; modulation means for modulating each of said carriers with said signal to provide a set of modulated carriers; beam-forming means for generating a plurality of beams, said beams being directed in different directions from said vehicle to said receivers allowing individual ones of said receivers to be illuminated by different individual ones of said beams; transmission means for transmitting each of said modulated carriers via at least one of said beams, a carrier frequency of at least one of said beams being different from a carrier frequency of another of said beams; wherein, in said communication system, each of said receivers has means for tuning the receiver to one of said carrier frequencies, respective ones of a plurality of said receivers being tuned to respective ones of said carrier frequencies to enable receptions of said signal at different locations via different carrier frequencies for reduction of multipath interference; said beam-forming means includes an array of antenna elements comprising a central antenna element surrounded by a set of peripheral antenna elements, respective ones of said antenna elements providing respective ones of said beams; said carrier means is operative to adjust a value of an individual one of said carrier frequencies; said communication system further comprises a communication link between an individual one of said receivers and said vehicle for directing said carrier means to adjust a value of a carrier frequency; said central antenna element is operative at a first carrier frequency, and said set of peripheral antenna elements is operative at a set of carrier frequencies different from said first carrier frequency; on the earth'"'"'s surface, a portion of one of said beams overlaps a portion of another of said beams to form an overlap region; and in each of said receivers, each of said tuning means has a signal strength selector for selecting a strongest of a plurality of said modulated carriers, and upon illumination of an individual one of said receivers within said overlap region, said signal strength selector enables said tuning means to tune to a modulated carrier having a largest signal strength. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A method of communicating between a vehicle traveling above the earth'"'"'s surface and plural receivers located distant from each other on the earth'"'"'s surface, the method comprising steps of:
-
generating a signal to be transmitted from said vehicle to said receivers; providing a plurality of carriers at a plurality of respective carrier frequencies; modulating each of said carriers with said signal to provide a set of modulated carriers; establishing an array of antenna elements comprising a central antenna element surrounded by a set of peripheral antenna elements; generating a plurality of beams by means of said antenna elements wherein respective ones of said antenna elements provide respective ones of said beams, said beams being directed in different directions from said vehicle to said receivers allowing individual ones of said receivers to be illuminated by different individual ones of said beams, wherein on the earth'"'"'s surface, a portion of one of said beams overlaps a portion of another of said beams to form an overlap region; operating said central antenna element at a first carrier frequency, and operating said set of peripheral antenna elements at a set of carrier frequencies different from said first carrier frequency; transmitting each of said modulated carriers via at least one of said beams, a carrier frequency of at least one of said beams being different from a carrier frequency of another of said beams; at each of said receivers, tuning the receiver to one of said carrier frequencies, respective ones of a plurality of said receivers being tuned to respective ones of said carrier frequencies to enable receptions of said signal at different locations via different carrier frequencies for reduction of multipath interference; providing said communication system with a communication link between an individual one of said receivers and said vehicle for directing an adjustment in a value of a carrier frequency; and in each of said receivers, selecting a strongest of a plurality of said modulated carriers and, upon illumination of an individual one of said receivers located within said overlap region, said tuning step includes a tuning of said individual receiver to a modulated carrier having a largest signal strength. - View Dependent Claims (13, 14)
-
Specification