function?ab（speichernwgMpauswahlhandles）;

%?Abw鋜tstastung?eines?Tiefpa?Signals
%
%?Inhalt:
%?-------
%?Abw鋜tstastung?wenn?eingegebene?Grenzfrequenz
%?kleiner?als?wg/M?ansonsten?Dezimation.
%?Achtung:?Das?hei遲?nicht?da?wir?in?Realit鋞?
%?je?nach?Signal?wahlweise?abw鋜tstasten?oder?
%?dezimieren?k鰊nen!!!
%
%?Ziel:?
%?-----
%?Zeigen?der?Auswirkung?von?Aliasing
%
%?L鰏ung:
%?-------
%?Anti-Aliasing?Filter?=>?Dezimation
%
%?Variablen:
%?----------
%?p??????Phasenversatz
%?M??????Dezimationsfaktor?
%?wg?????Grenzfrequenz?des?Tiefpass-Signals
%?
%?Funktionsaufruf:?z.?B.?abwaertstastung（0.15*pi4）

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%?Berechnung?des?bandbegrenzten?Signals
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%?Der?erste?Aufruf?mit?zwei?Parametern?bewirkt?die?Initialisierung
%?der?graphischen?Oberflaeche.
%?Wird?kein?Parameter?uebergeben?so?werden?zusaetzlich?wg?und?M?gesetzt.
%?Bei?jedem?weiteren?Aufruf?die?Parameter?nicht?mehr?setzen

if?nargin<4
????wg?=?0.15*pi;
????M?=?4;
????p?=?0;
????auswahl?=?1;
elseif?nargin<5
????auswahl?=?1;
end;

%?Graphische?Oberflaeche?initialisieren
%?und?uebergebene?Werte?in?GUI-Felder?eintragen
if?nargin<6
????ab_gui;
????handles?=?guihandles（ab_gui）;
????%?Systembild?plotten
????axes（handles.system）;
????image（imread（‘a(chǎn)b_graph.png‘））;?
????axis（[0?900?0?700]）;
????axis?off;
????speichern?=?0;
end;
set（handles.wg‘Value‘wg./pi）;
set（handles.wgtext‘String‘[num2str（wg./pi）]）;
set（handles.M‘Value‘M）;
set（handles.Mtext‘String‘M）;
set（handles.ptext‘String‘p）;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%?Ueberpruefung?auf?Aliasing
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if?（pi/M????set（handles.text‘String‘‘WARNUNG:?Aliasing‘）;
end;

%?Signal?ist?die?Impulsantwort?eines?Tiefpasses?
%?mit?der?Grenzfrequenz?wg?und?der?Filterlaenge?N
N=70;??????????????????????????%?Filterlaenge?

%?Entwurf?mit?Remez
Fre=[0?wg/pi-0.05?wg/pi?1];????%?Frequenz?[0?pi]->[0?1]
Mag=[1?1?0?0];?????????????????%?Amplitude
x=remez（N-1FreMag）;??????????%?Entwurf?mit?Remezverfahren

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%?Abtastung?mit?Dezimationsfaktor?4
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
x0=zeros（1N+p）;
x0（p+1:M:length（x））?=?x（p+1:M:length（x））;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%?Abw鋜tstastung?
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
y?=?x（p+1:M:length（x））;

switch?（auswahl）
????case?1
????????%?Plotten?des?Signals?und?dessen?Spektrum
????????if?speichern
????????????figure（10）;
????????????subplot（211）;
????????????zeichnen（x[‘Signal?x（n）‘]‘n‘‘‘‘Zeitbereich‘gca）;
????????????subplo

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件???????55286??2002-10-16?10:14??Multiratensysteme_MATLAB_14-07-2004\AAU.PNG
?????文件????????7798??2002-07-11?18:05??Multiratensysteme_MATLAB_14-07-2004\ab.m
?????文件???????15933??2003-04-02?11:05??Multiratensysteme_MATLAB_14-07-2004\ab_band.m
?????文件???????62952??2003-03-19?11:26??Multiratensysteme_MATLAB_14-07-2004\ab_band_gui.fig
?????文件???????12253??2003-04-02?10:46??Multiratensysteme_MATLAB_14-07-2004\ab_band_gui.m
?????文件???????25255??2002-06-20?16:25??Multiratensysteme_MATLAB_14-07-2004\ab_graph.png
?????文件???????49512??2002-07-11?17:52??Multiratensysteme_MATLAB_14-07-2004\ab_gui.fig
?????文件????????7688??2002-07-11?18:15??Multiratensysteme_MATLAB_14-07-2004\ab_gui.m
?????文件?????????543??2002-06-24?22:38??Multiratensysteme_MATLAB_14-07-2004\ARROW.M
?????文件???????17914??2003-02-11?15:16??Multiratensysteme_MATLAB_14-07-2004\ASYNAU.M
?????文件??????112240??2004-07-14?10:43??Multiratensysteme_MATLAB_14-07-2004\asynau_gui.fig
?????文件???????10988??2002-11-01?13:07??Multiratensysteme_MATLAB_14-07-2004\asynau_gui.m
?????文件????????8950??2002-07-11?18:46??Multiratensysteme_MATLAB_14-07-2004\auf.m
?????文件???????28686??2002-06-20?16:27??Multiratensysteme_MATLAB_14-07-2004\auf_graph.png
?????文件???????57624??2002-05-11?14:22??Multiratensysteme_MATLAB_14-07-2004\auf_gui.fig
?????文件????????5979??2002-07-11?18:46??Multiratensysteme_MATLAB_14-07-2004\auf_gui.m
?????文件?????????381??2003-10-07?15:05??Multiratensysteme_MATLAB_14-07-2004\ausblenden.m
?????文件?????????181??2002-08-15?16:52??Multiratensysteme_MATLAB_14-07-2004\ausblenden2.m
?????文件?????????180??2002-06-20?11:22??Multiratensysteme_MATLAB_14-07-2004\ausblenden_dezint.m
?????文件????????6565??2002-11-06?10:35??Multiratensysteme_MATLAB_14-07-2004\AUSGABE.M
?????文件??????296280??2004-07-14?11:01??Multiratensysteme_MATLAB_14-07-2004\DATEN.MAT
?????文件???????12208??2002-06-03?18:26??Multiratensysteme_MATLAB_14-07-2004\dcs.m
?????文件???????53545??2002-08-15?17:49??Multiratensysteme_MATLAB_14-07-2004\dcs_graph.png
?????文件???????63944??2003-02-25?09:32??Multiratensysteme_MATLAB_14-07-2004\dcs_gui.fig
?????文件????????7765??2002-06-03?18:45??Multiratensysteme_MATLAB_14-07-2004\dcs_gui.m
?????文件????????1000??1998-04-29?14:49??Multiratensysteme_MATLAB_14-07-2004\delta.m
?????文件????????1109??2003-09-24?11:59??Multiratensysteme_MATLAB_14-07-2004\delta_bp.m
?????文件????????9086??2003-03-19?08:55??Multiratensysteme_MATLAB_14-07-2004\dezimation.m
?????文件???????32175??2002-06-20?16:26??Multiratensysteme_MATLAB_14-07-2004\dezimation_graph.png
?????文件???????57944??2002-05-11?14:40??Multiratensysteme_MATLAB_14-07-2004\dezimation_gui.fig
?????文件????????5905??2002-05-11?14:42??Multiratensysteme_MATLAB_14-07-2004\dezimation_gui.m
............此處省略204個文件信息