Method of Utilizing Parametric Reflective Technology

Abstract

A system and method for encoding and decoding information by use of radio frequency antennas. The system includes one or more interrogator devices and RFID data tags. The RFID data tags include a plurality of antenna elements which are formed on a substrate or directly on an object. The antenna elements are oriented and have dimensions to provide polarization and phase information, whereby this information represents the encoded information on the RFID tag. The interrogator device scans an area and uses radar imaging technology to create an image of a scanned area. The device receives re-radiated RF signals from the antenna elements on the data tags, whereby the data tags are preferably represented on the image. The re-radiated RF signals preferably include polarization and phase information of each antenna element, whereby the information is utilized using radar signal imaging algorithms to decode the information on the RF data tag.

1 . A method for encoding information into an RF data tag comprising:
 converting information to be encoded into a predetermined bit coding scheme;   converting the bit coding scheme into at least one of a phase characteristic and a polarization characteristics; and   producing an antenna element having the at least one of the phase and polarization characteristics.   
   
   
       2 . The method of  claim 1  further comprising printing the antenna element on a substrate. 
   
   
       3 . The method of  claim 1  wherein the antenna element is adapted to re-radiate electromagnetic radiation having the at least one phase and polarization characteristics when receiving incident electromagnetic radiation at a predetermined frequency. 
   
   
       4 . The method of  claim 1  wherein the antenna element has an orientation and at least one dimension associated with the at least one of the polarization and phase characteristics. 
   
   
       5 . The method of  claim 1  wherein the antenna element is a reference antenna element. 
   
   
       6 . The method of  claim 1  wherein the antenna element is adapted to re-radiate an RF signal upon receiving an incident RF signal, wherein the re-radiated RF signal is able to be processed to decode the encoded information in the RF data tag. 
   
   
       7 . A method for reading data stored in an RF tag the method comprising:
 transmitting a plurality of RF signals, wherein at least two RF signals in the plurality have different polarization characteristics;   receiving a plurality of re-radiated RF signals from an RF data tag having an antenna element with polarization and phase information, wherein each re-radiated RF signal is associated with a corresponding transmitted RF signal and includes polarization information of the antenna element;   comparing the polarization information for each re-radiated RF signal to identify the antenna element; and   converting the polarization and phase information of the identified antenna element into data representative of information encoded in the antenna element.   
   
   
       8 . The method of  claim 7  further comprising storing the polarization and phase information for each received RF signal. 
   
   
       9 . The method of  claim 7  wherein comparing further comprises calculating elevation and azimuth compression data from the polarization and phase information to identify the RF data tag. 
   
   
       10 . The method of  claim 7  further comprising performing a signal image processing algorithm to the re-radiated RF signals to determine the polarization and phase information. 
   
   
       11 . The method of  claim 7  further comprising producing an image of the scanned area in which the electromagnetic radiation is transmitted and received, wherein the antenna element is present in the image. 
   
   
       12 . The method of  claim 7  wherein transmitting is performed in at least one of a radial motion and a translational motion. 
   
   
       13 . The method of  claim 7  wherein transmitting is performed from a plurality of separate transmitting and receiving sites which are synchronized.