wfsNoisePSD.hpp

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/** \file wfsNoisePSD.hpp
 * \author Jared R. Males (jaredmales@gmail.com)
 * \brief Declares and defines a function to calculate the measurement noise PSD
 * \ingroup mxAO_files
 *
 */
 
#ifndef __wfsNoisePSD_hpp__
#define __wfsNoisePSD_hpp__
 
namespace mx
{
namespace AO
{
namespace analysis
{
 
/// Populate a vector with the PSD of measurement noise given WFS parameters.
/**
 * \tparam realT is the real floating point type for calculations
 *
 * \ingroup mxAOAnalytic
 */
template <typename realT>
void wfsNoisePSD( std::vector<realT> &PSD, ///< [out] A pre-allocated vector which will be filled with the PSD value.
                  realT beta_p_k, ///< [in] The WFS \f$ \beta_p \f$ parameter (see Guyon, 2005 \cite{guyon_2005}).
                  realT Fg,       ///< [in] Total photons/sec used by the WFS
                  realT tau,      ///< [in] WFS Integration time [sec]
                  realT npx,      ///< [in] Number of pixesl used by the WFS
                  realT Fb,       ///< [in] Background flux, in photons/sec/pixel.
                  realT ron       ///< [in] Readout noise, in photons/pixel/read.
)
{
 
    realT snr2 = pow( Fg * tau, 2 ) / ( Fg * tau + npx * Fb * tau + npx * ron * ron );
 
    realT psd = 2 * pow( beta_p_k, 2 ) / snr2 * tau;
 
    for( size_t i = 0; i < PSD.size(); ++i )
    {
        PSD[i] = psd;
    }
}
 
} // namespace analysis
} // namespace AO
} // namespace mx
 
#endif //__wfsNoisePSD_hpp__