×

Phase shifters, interrogators, methods of shifting a phase angle of a signal, and methods of operating an interrogator

  • US 7,898,390 B2
  • Filed: 08/10/2006
  • Issued: 03/01/2011
  • Est. Priority Date: 03/09/1999
  • Status: Expired due to Fees
First Claim
Patent Images

1. An interrogator of a backscatter communication system comprising:

  • a transmitter configured to output a local continuous wave signal and a radio frequency continuous wave signal; and

    a receiver configured to receive the local continuous wave signal and a modulated radio frequency continuous wave signal, the receiver including;

    a phase shifter configured to adjust a phase angle of the local continuous wave signal by a phase shift angle, the phase shifter including a first power divider configured to provide a first component and a second component of the local continuous wave signal, plural mixers configured to scale the first component and the second component using the phase shift angle,and a second power divider configured to combine the scaled first component and the scaled second component to provide an adjusted continuous wave signal; and

    a coupler configured to combine the adjusted continuous wave signal and the modulated radio frequency continuous wave signal.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×