LALInspiralWaveCorrelate.c File Reference

Module to compute the correlation of two data sets. More...

Prototypes
void	LALInspiralWaveCorrelate (LALStatus *status, REAL4Vector *output, InspiralWaveCorrelateIn corrin)

Detailed Description

Module to compute the correlation of two data sets.

Author

Sathyaprakash, B. S.

Suitable only when REAL4VectorFFT is used (i.e. rfftwi_one of fftw).

Notation: The input struct has two vectors: signal1 and signal2. This module computes the correlation by shifting signal2 with respect to positive time-direction relative to signal1. Thus, if signal1 denotes the detector output in which a signal, say signal2, is present at time \(t_0,\) then the correlation peaks at \(t_0.\)

Prototypes

LALInspiralWaveCorrelate()

Description

The module expects two inputs signal1, signal2 in the Fourier-domain, computes their correlation weighted by the noise psd, and returns the correlated output in the time-domain. More precisely, given the Discrete Fourier transform (in the notation of {fftw}) \(H_k\) and \(Q_k\) of vectors \(h_k\) and \(q_k,\) \(k=0,\ldots n-1,\) this module computes the inverse Fourier transform of the weighted correlation \(C_k\) defined as

\[C_k = \frac{H_k Q_k + H_{n-k} Q_{n-k} }{S_k}, \ \ C_{n-k} = \frac{H_k Q_{n-k} + H_{n-k} Q_k }{S_k}, \ \ k=1,\ldots,\frac{n}{2}-1.\]

Uses

LALREAL4VectorFFT()

Definition in file LALInspiralWaveCorrelate.c.

Go to the source code of this file.

Function Documentation

LALInspiralWaveCorrelate()

void LALInspiralWaveCorrelate	(	LALStatus *	status,
		REAL4Vector *	output,
		InspiralWaveCorrelateIn	corrin
	)

Definition at line 66 of file LALInspiralWaveCorrelate.c.