Autonomous vehicle ranging system with polarized antenna

Abstract

A front end of a radar system is provided with a first front end apparatus and a second front end apparatus. A first transmit planar component and a first receive planar component in the first front end apparatus are arranged to be perpendicular to one another. A second transmit planar component and a second receive planar component in the second front end apparatus are arranged to be perpendicular to one another. A linear array of antennas is located along a second end of each planar component. Polarization of a first set of waves transmitted from the linear array of antennas of the first transmit planar component and polarization of a second set of waves transmitted from the linear array of antennas of the second transmit planar component are perpendicular to one another.

1 - 15 . (canceled) 
     
     
         16 . A method of detecting an object, the method comprising:
 providing a first linear array of transmit antennas and a second linear array of transmit antennas, the first linear array of transmit antennas and the second linear array of transmit antennas being parallel to one another;   providing a first linear array of receive antennas and a second linear array of receive antennas, the first linear array of receive antennas and the second linear array of receive antennas being parallel to one another;   arranging the first linear array of transmit antennas and the first linear array of receive antennas to be perpendicular to one another;   arranging the second linear array of transmit antennas and the second linear array of receive antennas to be perpendicular to one another;   phase-shifting first waves by propagating the first waves through a first Rotman lens that is in operative communication with the first linear array of transmit antennas;   phase-shifting second waves by propagating the second waves through a second Rotman lens that is in operative communication with the second linear array of transmit antennas;   transmitting the first waves through the first linear array of transmit antennas;   transmitting the second waves through the second linear array of transmit antennas;   receiving the first waves reflected by an object through the first linear array of receive antennas;   receiving the second waves reflected by an object through the second linear array of receive antennas;   propagating the first waves reflected by an object through a third Rotman lens that is in operative communication with the first linear array of receive antennas; and   propagating the second waves reflected by an object through a fourth Rotman lens that is in operative communication with the second linear array of receive antennas.   
     
     
         17 . The method of  claim 16 , wherein polarization of the first waves transmitted through the first linear array of transmit antennas and polarization of the second waves transmitted through the second linear array of transmit antennas are perpendicular to one another. 
     
     
         18 . The method of  claim 17 , further comprising rotating a polarization of the first waves by 90 degrees an odd number of times before the first waves propagate from the first linear array of transmit antennas, and rotating a polarization of the second waves by 90 degrees an even number of times before the second waves propagate from the second linear array of transmit antennas. 
     
     
         19 . The method of  claim 18 , further comprising rotating a polarization of the first waves by 90 degrees an odd number of times as the first waves propagate from the first transmit logic to a first receive logic, and rotating a polarization of the second waves by 90 degrees the same odd number of times as the second waves propagate form the second transmit logic to a second receive logic. 
     
     
         20 . The method of  claim 16 , further comprising correlating the first waves from a first transmit logic with the first waves reflected by an object and correlating the second waves from a second transmit logic with the second waves reflected by an object.