function?y=awgn（varargin）
%AWGN?Add?white?Gaussian?noise?to?a?signal.
%???Y?=?AWGN（XSNR）?adds?white?Gaussian?noise?to?X.??The?SNR?is?in?dB.
%???The?power?of?X?is?assumed?to?be?0?dBW.??If?X?is?complex?then?
%???AWGN?adds?complex?noise.
%
%???Y?=?AWGN（XSNRSIGPOWER）?when?SIGPOWER?is?numeric?it?represents?
%???the?signal?power?in?dBW.?When?SIGPOWER?is?‘measured‘?AWGN?measures
%???the?signal?power?before?adding?noise.
%
%???Y?=?AWGN（XSNRSIGPOWERS）?uses?S?which?is?a?random?stream?handle?to
%???generate?random?noise?samples?with?RANDN.?If?S?is?an?integer?then
%???resets?the?state?of?RANDN?to?S.?The?latter?usage?is?obsoleted?and?may
%???be?removed?in?a?future?release.??If?you?want?to?generate?repeatable
%???noise?samples?then?provide?the?handle?of?a?random?stream?or?use?reset
%???method?on?the?default?random?stream.??Type?‘help?RandStream‘?for?more
%???information.
%
%???Y?=?AWGN（XSNRSIGPOWERSTATE）?resets?the?state?of?RANDN?to?STATE.
%???This?usage?is?deprecated?and?may?be?removed?in?a?future?release.
%
%???Y?=?AWGN（...?POWERTYPE）?specifies?the?units?of?SNR?and?SIGPOWER.
%???POWERTYPE?can?be?‘db‘?or?‘linear‘.??If?POWERTYPE?is?‘db‘?then?SNR
%???is?measured?in?dB?and?SIGPOWER?is?measured?in?dBW.??If?POWERTYPE?is
%???‘linear‘?then?SNR?is?measured?as?a?ratio?and?SIGPOWER?is?measured
%???in?Watts.
%
%???Example?1:?
%????????%?To?specify?the?power?of?X?to?be?0?dBW?and?add?noise?to?produce
%????????%?an?SNR?of?10dB?use:
%????????X?=?sqrt（2）*sin（0:pi/8:6*pi）;
%????????Y?=?awgn（X100）;
%
%???Example?2:?
%????????%?To?specify?the?power?of?X?to?be?3?Watts?and?add?noise?to
%????????%?produce?a?linear?SNR?of?4?use:
%????????X?=?sqrt（2）*sin（0:pi/8:6*pi）;
%????????Y?=?awgn（X43‘linear‘）;
%
%???Example?3:?
%????????%?To?cause?AWGN?to?measure?the?power?of?X?and?add?noise?to
%????????%?produce?a?linear?SNR?of?4?use:
%????????X?=?sqrt（2）*sin（0:pi/8:6*pi）;
%????????Y?=?awgn（X4‘measured‘‘linear‘）;
%
%???Example?4:?
%????????%?To?specify?the?power?of?X?to?be?0?dBW?add?noise?to?produce
%????????%?an?SNR?of?10dB?and?utilize?a?local?random?stream?use:
%????????S?=?RandStream（‘mt19937ar‘‘seed‘5489）;
%????????X?=?sqrt（2）*sin（0:pi/8:6*pi）;
%????????Y?=?awgn（X100S）;
%
%???Example?5:?
%????????%?To?specify?the?power?of?X?to?be?0?dBW?add?noise?to?produce
%????????%?an?SNR?of?10dB?and?produce?reproducible?results?use:
%????????reset（RandStream.getGlobalStream）
%????????X?=?sqrt（2）*sin（0:pi/8:6*pi）;
%????????Y?=?awgn（X100S）;
%
%
%???See?also?WGN?RANDN?RandStream/RANDN?and?BSC.

%???Copyright?1996-2011?The?MathWorks?Inc.

%?---?Initial?checks
error（nargchk（25nargin‘struct‘））;

%?---?Value?set?indicators?（used?for?the?string?flags）
pModeSet????=?0;
measModeSet?=?0;

%?---?Set?default?values
sigPower?=?0;
pMode????=?‘db‘;
measMode?=?‘specify‘;
state????=?[];

%?---?Placeholder?for?the?signature?string
sigStr?=?‘‘;

%?---?Identify?string?and?numeric?arguments
isStream?=?false;
for?n=1:nargin
???if（n>1）
??????sigStr（size（sigStr2）+1）?=?‘/‘;
??

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????7390??2014-12-25?20:01??My_DSP\awgn.m

?????文件???????3713??2014-12-25?23:38??My_DSP\Dail.m

?????文件?????383567??2014-12-26?14:14??My_DSP\dailing.mat

?????文件?????304531??2015-01-04?13:39??My_DSP\Dailing.txt

?????文件???????4620??2014-12-26?14:34??My_DSP\Detect.m

?????文件????????510??2014-12-26?01:49??My_DSP\Document.txt

?????文件?????719744??2015-01-05?22:13??My_DSP\DSP實驗報告.pdf

?????文件?????????45??2014-12-25?23:47??My_DSP\TestSignal.txt

?????文件???????6563??2014-12-25?20:01??My_DSP\wgn.m

?????目錄??????????0??2015-01-05?22:13??My_DSP

-----------?---------??----------?-----??----

??????????????1430683????????????????????10