# v_usasi

## PURPOSE

V_USASI generates N samples of USASI noise at sample frequency FS X=(N,FS)

## SYNOPSIS

function x=v_usasi(n,fs)

## DESCRIPTION

    V_USASI generates N samples of USASI noise at sample frequency FS X=(N,FS)

## CROSS-REFERENCE INFORMATION

This function calls:

- v_randfilt V_RANDFILT Generate filtered gaussian noise without initial transient

This function is called by:

## SOURCE CODE

    0001 function x=v_usasi(n,fs)
    0002 %V_USASI generates N samples of USASI noise at sample frequency FS X=(N,FS)
    0003
    0004 % This routine is based on the USASI noise defined in [1] which was later
    0005 % reissued as [2]. USASI noise is intended to simulate the long-term average
    0006 % of typical audio program material. The routine does not currently implement
    0007 % the pulsation at 2.5Hz 12.5% duty cycle that is recommended by the standard.
    0008 % Also it should probably be scaled to a well-defined power.
    0009 %
    0010 %  [1] NRSC AM Reemphasis, Deemphasize, and Broadcast Audio Transmission Bandwidth Specifications,
    0011 %      EIA-549 Standard, Electronics Industries Association , July 1988.
    0012 %  [2] NRSC AM Reemphasis, Deemphasize, and Broadcast Audio Transmission Bandwidth Specifications,
    0013 %      NRSC-1-A Standard, Sept 2007, Online: http://www.nrscstandards.org/SG/NRSC-1-A.pdf
    0014
    0015 %      Copyright (C) Mike Brookes 1997
    0016 %      Version: $Id: v_usasi.m 10865 2018-09-21 17:22:45Z dmb $
    0017 %
    0018 %   VOICEBOX is a MATLAB toolbox for speech processing.
    0019 %   Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html
    0020 %
    0021 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    0022 %   This program is free software; you can redistribute it and/or modify
    0023 %   it under the terms of the GNU Lesser General Public License as published by
    0024 %   the Free Software Foundation; either version 3 of the License, or
    0025 %   (at your option) any later version.
    0026 %
    0027 %   This program is distributed in the hope that it will be useful,
    0028 %   but WITHOUT ANY WARRANTY; without even the implied warranty of
    0029 %   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    0030 %   GNU Lesser General Public License for more details.
    0031 %
    0032 %   You can obtain a copy of the GNU Lesser General Public License from
    0033 %   https://www.gnu.org/licenses/ .
    0034 %
    0035 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    0036
    0037 if nargin<2 fs=8000; end
    0038 b=[1 0 -1];
    0039 a=poly(exp(-[100 320]*2*pi/fs));
    0040
    0041 x=v_randfilt(b,a,n);