Package ptolemy.actor.lib.comm

Class DeScrambler

  • All Implemented Interfaces:
    java.lang.Cloneable, Actor, Executable, FiringsRecordable, Initializable, TypedActor, Changeable, Debuggable, DebugListener, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable
    public class DeScrambler
extends Transformer
    Descramble the input bit sequence using a feedback shift register. The taps of the feedback shift register are given by the polynomial parameter. The initial state of the shift register is given by the initialState parameter. This is a self-synchronizing descrambler that will exactly reverse the operation of the Scrambler if the polynomials are the same. The low-order bit of the polynomial should always be set. For more information, see the documentation for the Scrambler actor and Lee and Messerschmitt, Digital Communication, Second Edition, Kluwer Academic Publishers, 1994, pp. 595-603.

    Since:
    Ptolemy II 3.0
    Version:
    $Id$
    Author:
    Edward A. Lee and Ye Zhou
    Pt.AcceptedRating:
    Red (cxh)
    Pt.ProposedRating:
    Red (eal)

    • Field Detail

      • polynomial

        public Parameter polynomial
        Integer defining a polynomial with binary coefficients. The coefficients indicate the presence (1) or absence (0) of a tap in a feedback shift register. This parameter should contain a positive integer with the lower-order bit being 1. Its default value is the integer 0440001.

      • initialState

        public Parameter initialState
        Integer defining the initial state of the shift register. The n-th bit of the integer indicates the value of the n-th register. This parameter should be a non-negative integer. Its default value is the integer 1.