Derotation.h

//-*-C++-*-
/***************************************************************************
 *
 *   Copyright (C) 2020 by Willem van Straten
 *   Licensed under the Academic Free License version 2.1
 *
 ***************************************************************************/
 
// dspsr/Signal/General/dsp/Derotation.h
 
#ifndef __Derotation_h
#define __Derotation_h
 
#include "dsp/PlasmaResponse.h"
#include "Pulsar/Faraday.h"
 
namespace dsp {
 
  /* This class implements the phase-coherent rotation removal kernel, as
     determined by the frequency response of the interstellar medium. */
 
  class Derotation : public PlasmaResponse 
  {
 
  public:
 
    Derotation ();
 
    double delay_time (double freq) const;
 
    void prepare (const Observation* input, unsigned channels);
 
    void set_rotation_measure (double dm);
 
    double get_rotation_measure () const;
 
  protected:
 
    Calibration::Faraday birefringence;
 
    void build (unsigned ndat, unsigned nchan);
 
    friend class PlasmaResponse;
 
    void build_setup (double chan_freq);
 
    Jones<float> build_compute (double chan_freq, double freq);
 
 
    std::vector<bool> supported_channels;
  };
 
}
 
#endif