×

System for reducing the affects of signal fading on received signals

  • US 5,191,598 A
  • Filed: 02/07/1991
  • Issued: 03/02/1993
  • Est. Priority Date: 02/16/1990
  • Status: Expired due to Term
First Claim
Patent Images

1. A method for reducing the influence of signal fading in a Viterbi-receiver, comprising the steps of:

  • (a) receiving radio signals on at least two mutually spaced apart antennas;

    (b) sampling signals received from said antennas;

    (c) determining a channel estimated including at least two part channel estimates corresponding respectively to said at least two antennas based on an estimate of a channel transmission function; and

    (d) processing said channel estimate in accordance with a Viterbi-algorithm wherein symbols are assumed for state transitions of said Viterbi-algorithm, said processing including;

    (e) calculating for each state transition of the Viterbi-algorithm assumed input signals based on said assumed symbols and said part channel estimates;

    (f) calculating part metric values for each part channel estimate based on said received antenna signal corresponding to said part channel estimates and said corresponding assumed input signal;

    (g) calculating for each current state transition between an old and a new state in said Viterbi-algorithm a current metric value from a preceding metric value corresponding to said old state combined with a weighted sum of said part metric values; and

    (h) selecting a smallest of said metric values at transition to said new state.

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