×

QPSK DEMODULATOR

  • US 20170317871A1
  • Filed: 09/22/2016
  • Published: 11/02/2017
  • Est. Priority Date: 04/29/2016
  • Status: Active Grant
First Claim
Patent Images

1. A bowknot quadrature phase-shift keying demodulator comprisinga delay circuit, receiving a bowknot quadrature phase-shift keying (BQPSK) signal, delaying said BQPSK signal by a first delay time to output a first delayed signal, and delaying said BQPSK signal by a total delay time to output a second delayed signal or an opposite-phase second delayed signal, wherein said opposite-phase second delayed signal is an opposite-signal of said second delayed signal;

  • anda decision-making circuit, electrically connected with said delay circuit, mixing said BQPSK signal with said second delayed signal or said opposite-phase second delayed signal to generate a first heterodyne signal, sampling said BQPSK signal according to said first heterodyne signal to output an I-channel data signal of said BQPSK signal, mixing said first delayed signal with said BQPSK signal to generate a second heterodyne signal, and sampling said second heterodyne signal according to said first heterodyne signal to output a Q-channel data signal of said BQPSK signal, wherein said first delay time and said total delay time meets following relationships;

    0.125T≦

    TD1

    0.375T, 0.375T<

    TD<

    0.625T, 0.125T≦

    TD−

    TD1<

    0.5T, wherein TD is said total delay time, TD1 is said first delay time, and T is a period of a carrier wave of said BQPSK signal.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×