System and method for launching guided electromagnetic waves with channel feedback

Abstract

In accordance with one or more embodiments, a transceiver is configured to generate a first signal in response to receiving a first guided electromagnetic wave from a remote system via a launcher. A controller is configured to generate a channel quality indicator in response to the first signal. The transceiver is further configured to generate a second signal that conveys the channel quality indicator. The launcher, responsive to the second signal, is further configured to launch a second guided electromagnetic wave that conveys the channel quality indicator to the remote system, wherein the second guided electromagnetic wave is guided by the transmission medium and propagates along the transmission medium.

What is claimed is: 
     
         1 . A system comprising:
 a launcher configured to receive a first guided electromagnetic wave, from a remote system, that is guided by a transmission medium and propagates along the transmission medium without requiring an electrical return path;   a lens configured to direct electromagnetic waves, launched by the launcher, onto a surface of the transmission medium;   a transceiver configured to generate a signal in response to receiving the first guided electromagnetic wave; and   a controller configured to generate a channel quality indicator in response to the signal and adjust an impedance matching circuit based on the channel quality indicator,   wherein the launcher is further configured to launch a second guided electromagnetic wave that conveys the channel quality indicator to the remote system, and   wherein the second guided electromagnetic wave is launched toward the lens for redirecting onto the surface of the transmission medium, is guided by the transmission medium, and propagates along the transmission medium.   
     
     
         2 . The system of  claim 1 , wherein the launcher includes an array of antennas having an aperture, and wherein the controller adjusts the aperture of the array of antennas responsive to the channel quality indicator. 
     
     
         3 . The system of  claim 2 , wherein the array of antennas comprises an array of polyrod antennas. 
     
     
         4 . The system of  claim 3 , wherein each polyrod antennas in the array of polyrod antennas includes a tapered dielectric rod. 
     
     
         5 . The system of  claim 1 , wherein the lens comprises a dichroic aspheric lens. 
     
     
         6 . The system of  claim 5 , wherein the dichroic aspheric lens comprises a convex surface. 
     
     
         7 . The system of  claim 1 , wherein the first guided electromagnetic wave propagates along the transmission medium via a plurality of guided wave modes, and wherein each of the plurality of guided wave modes has a corresponding velocity and a corresponding dispersion. 
     
     
         8 . The system of  claim 1 , wherein the channel quality indicator is generated by determining an impulse response. 
     
     
         9 . A method comprising:
 receiving, via a launcher, a first guided electromagnetic wave from a remote system that is guided by a transmission medium and propagates along the transmission medium without requiring an electrical return path;   generating, via a transceiver, a signal in response to receiving the first guided electromagnetic wave;   generating, via a controller, a channel quality indicator in response to the signal;   adjusting, via the controller, an impedance matching circuit based on the channel quality indicator; and   launching, via the launcher, a second guided electromagnetic wave that conveys the channel quality indicator to the remote system, wherein the second guided electromagnetic wave is launched toward a reflector configured to direct the second guided electromagnetic wave onto a surface of the transmission medium, is guided by the transmission medium, and propagates along the transmission medium.   
     
     
         10 . The method of  claim 9 , wherein the launcher includes an array of antennas having an aperture, and wherein the controller adjusts the aperture of the array of antennas responsive to the channel quality indicator. 
     
     
         11 . The method of  claim 10 , wherein the array of antennas comprises an array of polyrod antennas. 
     
     
         12 . The method of  claim 9 , wherein the reflector comprises an aspheric mirror. 
     
     
         13 . The method of  claim 9 , wherein the reflector is composed of multiple portions that are assembled together so as to at least partially surround the transmission medium. 
     
     
         14 . The method of  claim 9 , wherein the first guided electromagnetic wave propagates along the transmission medium via a plurality of guided wave modes, and wherein each of the plurality of guided wave modes has a corresponding velocity and a corresponding dispersion. 
     
     
         15 . The method of  claim 9 , wherein the channel quality indicator is generated by determining an impulse response. 
     
     
         16 . A system comprising:
 means for receiving a first guided electromagnetic wave from a remote system that is guided by a transmission medium and propagates along the transmission medium without requiring an electrical return path;   means for generating a signal in response to receiving the first guided electromagnetic wave;   means for generating a channel quality indicator by determining an impulse function and adjusting an impedance matching circuit based on the channel quality indicator;   means for directing electromagnetic waves, launched by the system, onto a surface of the transmission medium; and   means for launching a second guided electromagnetic wave that conveys the channel quality indicator to the remote system, wherein the second guided electromagnetic wave is directed onto the surface of the transmission medium by the means for directing electromagnetic waves, is guided by the transmission medium, and propagates along the transmission medium.   
     
     
         17 . The system of  claim 16 , wherein the means for launching the second guided electromagnetic wave includes an array of antennas having an aperture. 
     
     
         18 . The system of  claim 17 , wherein the array of antennas comprises an array of polyrod antennas. 
     
     
         19 . The system of  claim 18 , wherein the array of polyrod antennas comprises a plurality of tapered dielectric rods. 
     
     
         20 . The system of  claim 16 , wherein the first guided electromagnetic wave propagates along the transmission medium via a plurality of guided wave modes, and wherein each of the plurality of guided wave modes has a corresponding velocity and a corresponding dispersion.