×

Time-of-flight radio location system

  • US 5,661,490 A
  • Filed: 04/23/1996
  • Issued: 08/26/1997
  • Est. Priority Date: 04/12/1993
  • Status: Expired due to Term
First Claim
Patent Images

1. An apparatus for measuring time-of-flight of an electromagnetic pulse, comprising:

  • a transmitter which transmits a sequence of electromagnetic pulses in response to a transmit timing signal;

    a receiver which samples the sequence of electromagnetic pulses with controlled timing, in response to a receive timing signal, and generates a sample signal in response to the samples;

    a timing circuit which supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver, the receive timing signal causing the receiver to sample the sequence of electromagnetic pulses such that time between transmission of pulses in the sequence and sampling by the receiver sweeps over a range of delays;

    an envelope detector for converting the sample signal to a unipolar signal to eliminate effects of antenna orientation mismatch;

    a sample detection circuit which in response to the sample signal and the timing circuit indicates a time-of-flight between the transmitter and the receiver of pulses in the sequence.

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