Air coil RF transponder and method of making same

Abstract

An RF air coil transponder includes a rotatable carrier, such as a rigid reel. A coil is wound about the reel and at least one field influencing body for influencing the electric and/or the magnetic field within the coil is supported by the reel. The rigidity of the reel enables the coil to keep its form and guarantees precise distances between windings, especially when a winding machine forms the coil. Adjusting the angular position, shape, composition, size, and/or surface are of the body effects adjustment of the resonant frequency.

1 - 32 . (canceled) 
   
   
       33 . An RF transponder, comprising:
 a casing;   a rigid carrier rotatably mounted within the casing;   a coil wound about the rigid carrier; and   at least one field-influencing body mounted on the rigid carrier, at least one characteristic of the at least one field-influencing body influencing a resonant frequency of the RF transponder.   
   
   
       34 . The RF transponder of  claim 33 , wherein the casing is composed of plastic. 
   
   
       35 . The RF transponder of  claim 33 , wherein the rigid carrier is a solid reel composed of an electrically insulating material. 
   
   
       36 . The RF transponder of  claim 35 , wherein the electrically insulating material is plastic. 
   
   
       37 . The RF transponder of  claim 33 , wherein the at least one characteristic of the at least one field-influencing body influences at least one of a magnetic field and an electrical field. 
   
   
       38 . The RF transponder of  claim 33 , wherein the at least one characteristic of the at least one field-influencing body is at least one of a shape, a size, a surface area, a composition, and an angular position of the at least one field-influencing body. 
   
   
       39 . The RF transponder of  claim 38 , wherein the shape of the at least one field-influencing body is cylindrical. 
   
   
       40 . The RF transponder of  claim 38 , wherein the composition of the at least one field-influencing body is a magnetic metal. 
   
   
       41 . The RF transponder of  claim 40 , wherein the magnetic metal is aluminum. 
   
   
       42 . The RF transponder of  claim 33 , further comprising a fixed field-influencing body attached to the casing, at least one characteristic of the fixed field-influencing body influencing a resonant frequency of the RF transponder. 
   
   
       43 . The RF transponder of  claim 42 , wherein the at least one characteristic of the fixed field-influencing body is at least one of a shape, a size, a surface area, a composition, and an angular position of the fixed field-influencing body. 
   
   
       44 . The RF transponder of  claim 43 , wherein the shape of the fixed field-influencing body is cylindrical. 
   
   
       45 . The RF transponder of  claim 43 , wherein the composition of the fixed field-influencing body is a magnetic metal. 
   
   
       46 . The RF transponder of  claim 45 , wherein the magnetic metal is aluminum. 
   
   
       47 . The RF transponder of  claim 33 , further comprising at least one electrical component attached to the rigid carrier. 
   
   
       48 . The RF transponder of  claim 47 , wherein the at least one electrical component is an integrated circuit. 
   
   
       49 . A method of manufacturing an RF transponder, comprising:
 rotatably mounting a rigid carrier within a casing;   winding a coil about the rigid carrier; and   mounting at least one field-influencing body on the rigid carrier, at least one characteristic of the at least one field-influencing body influencing a resonant frequency of the RF transponder.   
   
   
       50 . The method of  claim 49 , wherein the rigid carrier is a solid reel composed of an electrically insulating material. 
   
   
       51 . The method of  claim 49 , wherein the at least one characteristic of the at least one field-influencing body influences at least one of a magnetic field and an electrical field. 
   
   
       52 . The method of  claim 49 , wherein the at least one characteristic of the at least one field-influencing body is at least one of a shape, a size, a surface area, a composition, and an angular position of the at least one field-influencing body. 
   
   
       53 . The method of  claim 49 , further comprising attaching a fixed field-influencing body to the casing, at least one characteristic of the fixed field-influencing body influencing a resonant frequency of the RF transponder. 
   
   
       54 . The method of  claim 53 , wherein the at least one characteristic of the fixed field-influencing body is at least one of a shape, a size, a surface area, a composition, and an angular position of the fixed field-influencing body. 
   
   
       55 . The method of  claim 49 , further comprising attaching at least one electrical component to the rigid carrier. 
   
   
       56 . A method of adjusting an RF transponder, the RF transponder comprising a casing; a rigid carrier rotatably mounted within the casing; a coil wound about the rigid carrier; and at least one field-influencing body mounted on the rigid carrier, at least one characteristic of the at least one field-influencing body influencing a resonant frequency of the RF transponder, the method comprising:
 determining a resonant frequency of the RF transponder;   comparing the determined resonant frequency with a desired resonant frequency of the RF transponder; and   if the determined resonant frequency is not equivalent to the desired resonant frequency, adjusting the at least one characteristic of the at least one field-influencing body.   
   
   
       57 . The method of  claim 56 , wherein the at least one characteristic of the at least one field-influencing body is at least one of a shape, a size, a surface area, a composition, and an angular position of the at least one field-influencing body. 
   
   
       58 . The method of  claim 56 , the RF transponder further comprising a fixed field-influencing body attached to the casing, at least one characteristic of the fixed field-influencing body influencing a resonant frequency of the RF transponder, the method further comprising the step of:
 if the determined resonant frequency is not equivalent to the desired resonant frequency, adjusting the at least one characteristic of the fixed field-influencing body.   
   
   
       59 . The method of  claim 58 , wherein the at least one characteristic of the fixed field-influencing body is at least one of a shape, a size, a surface area, a composition, and an angular position of the fixed field-influencing body.