US 7,515,021 B2
Split-ring coupler incorporating dual resonant sensors
Victor Alexandrovich Kalinin, Headington (United Kingdom); and John Peter Beckley, Bicester (United Kingdom)
Assigned to Transense Technologies PLC, (United Kingdom)
Appl. No. 11/587,455
PCT Filed Apr. 15, 2005, PCT No. PCT/GB2005/001474
§ 371(c)(1), (2), (4) Date Oct. 24, 2006,
PCT Pub. No. WO2005/104292, PCT Pub. Date Nov. 03, 2005.
Claims priority of application No. 0409251.6 (GB), filed on Apr. 26, 2004.
Prior Publication US 2008/0061910 A1, Mar. 13, 2008
Int. Cl. H01P 1/06 (2006.01); H03H 9/00 (2006.01); H01P 5/12 (2006.01)
U.S. Cl. 333—261  [333/24 R] 20 Claims
OG exemplary drawing
 
1. A split ring coupler comprising:
a stator ring having at least one split in it such that the stator has at least a first and a second end;
a rotor ring having at least one split in it such that the rotor ring has at least a first and a second end, said rotor ring being oriented substantially coaxially with and axially spaced apart from said stator ring; and
at least one SAW resonator electrically coupled between said first and second ends of the rotor ring, wherein neither of said ends of said stator ring are directly connected to ground, and wherein one end of the stator ring is connected to earth through a resistor the resistance of which is greater than the characteristic impedance of a signal line, and each of the rotor and stator rings having a ground plane confining electromagnetic field and reducing radiation, so as to form microstrip coupled lines.