HARK version 1.1.0 Document : CMChannelSelector

6.2.3 CMChannelSelector

Module Overview

From a multi-channel correlation matrix, get only the specified channel data in the specified sequence.

Requested Files

None.

Usage

In what case is the node used?

From the multi-channel correlation matrix that was input, using this when channels not required are to be deleted, or the channel sequence is to be exchanged, or when the channel is to be copied.

Typical Examples

Figure. 6.12 shows a usage example for the CMChannelSelector node. The input terminal is connected to a correlation matrix calculated from CMMakerFromFFT or CMMakerFromFFTwithFlag , etc. (type is Matrix<complex<float> > type, but to handled a correlation matrix, convert the three dimensional complex array to a two dimensional complex array and then output).

$\includegraphics[width=0.8\linewidth ]{fig/modules/CMChannelSelector.eps}$

Figure 6.12: Network Example using CMChannelSelector

I/O and property setting of the node

Table 6.16: Parameter list of CMChannelSelector

Parameter	Type	Default	Unit	Description
NB_CHANNELS	`int`	8		Number of channels $M$ of input signal
LENGTH	`int`	512		Frame length $NFFT$
SELECTOR	`Vector<int>`	`<Vector<int> >`		Specifies the channel numbers to be output

Input

INPUTCM: Matrix<complex<float> > type. Correlation matrix for each frequency bin. $M$ -th order complex square array with correlation matrix inputs $NFFT/2 + 1$ items. Matrix<complex<float> > indicates the row of frequency ( $NFFT/2 + 1$ rows), and column of complex correlation matrix ( $M * M$ columns).

Output

OUTPUTCM: Matrix<complex<float> > type. Same as INPUTCM.

Parameter

NB_CHANNELS

int type. Number of channels in the input signal. Equivalent to the order of the correlation matrix. Must be matched with the order of the former correlation matrix used. Default value is 8.

LENGTH

int type. Default value is 512. FFT points at the time of Fourier transform. Must be matched till the former FFT points.

SELECTOR

Vector<int> type. No default value (<Vector<int> >). Specifies the channel numbers to be used. Channel numbers start from 0.

Example From 5 channels (0-4), specify <Vector <int> 2 3 4> when using only channels 2, 3, 4. When exchanging the 3rd channel and 4th channel, specify <Vector <int> 0 1 2 4 3 5>.

Module Description

From a correlation matrix containing a complex three-dimensional array of input data of size $k \times M \times M$ , extract only the correlation matrix of the specified channel, and output the new complex three-dimensional array of data of size $k \times M \times M$ . $k$ is the number of frequency bins ( $k = NFFT/2+1$ ), $M$ is the number of input channels, and $M’$ is the number of output channels.