helps for understanding how to implement "sinusx" function in the calcSNR.m file

Hello,

I am taking a course on data converters. our textbook is data converter by malloberti. in the chapter 3, example code 3.2 , there is a function named calcSNR.m which contains a function "sinusx" which has not been defined. Can you help me to understand how to implement sinusx?

here it is calcSNR.m :

function [snrdB,ptotdB,psigdB,pnoisedB] = calcSNR(vout,f,fB,w,N)

% SNR calculation in the time domain (P. Malcovati, S. Brigati)

% function [snrdB,ptotdB,psigdB,pnoisedB] = calcSNR(vout,f,fB,w,N)

% vout: Sigma-Delta bit-stream taken at the modulator output

% f: Normalized signal frequency (fs -> 1)

% fB: Base-band frequency bins

% w: windowing vector

% N: samples number

%

% snrdB: SNR in dB

% ptotdB: Bit-stream power spectral density (vector)

% psigdB: Extracted signal power spectral density (vector)

% pnoisedB: Noise power spectral density (vector)

%

fB=ceil(fB);

signal=(N/sum(w))*sinusx(vout(1:N).*w,f,N); % Extracts sinusoidal signal

noise=vout(1:N)-signal; % Extracts noise components

stot=((abs(fft((vout(1:N).*w)'))).^2); % Bit-stream PSD

ssignal=(abs(fft((signal(1:N).*w)'))).^2; % Signal PSD

snoise=(abs(fft((noise(1:N).*w)'))).^2; % Noise PSD

pwsignal=sum(ssignal(1:fB)); % Signal power

pwnoise=sum(snoise(1:fB)); % Noise power

snr=pwsignal/pwnoise;

snrdB=dbp(snr);

norm=sum(stot)/sum(vout(1:N).^2)*N; % PSD normalization

if nargout > 1

ptot=stot/norm;

ptotdB=dbp(ptot);

end

if nargout > 2

psig=ssignal/norm;

psigdB=dbp(psig);

end

if nargout > 3

pnoise=snoise/norm;

pnoisedB=dbp(pnoise);

end

Answer 1

[Walter Roberson]

https://www.edaboard.com/threads/sigma-delta-calculation-of-snr.297827/