×

Transceiver circuits for TDMA system with variable frequency second local oscillator

  • US 5,987,309 A
  • Filed: 06/26/1996
  • Issued: 11/16/1999
  • Est. Priority Date: 07/03/1995
  • Status: Expired due to Term
First Claim
Patent Images

1. A transceiver circuit for use with a time division multiple access system, the transceiver circuit comprising:

  • a first local oscillator for generating a first local frequency signal;

    a second local oscillator comprising a frequency synthesizer having a reference frequency that is higher than a frequency channel step, and generating a second local frequency signal having a frequency dependent on whether the transceiver circuit is in the transmitting mode or the receiving mode;

    a heterodyne receiver circuit comprising;

    a first frequency converter for converting a received signal into a first intermediate frequency signal, anda second frequency converter for converting the first intermediate frequency signal into a second intermediate frequency signal having a frequency equal to a differential frequency between the first intermediate frequency and the second local frequency signal; and

    a transmitter circuit.

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