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67  <div class="navpath"><b>itpp</b>::<a class="el" href="classitpp_1_1Raised__Cosine.html">Raised_Cosine</a>
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71<h1>itpp::Raised_Cosine&lt; T1 &gt; Class Template Reference</h1><!-- doxytag: class="itpp::Raised_Cosine" --><!-- doxytag: inherits="Pulse_Shape&lt; T1, double, T1 &gt;" -->Raised Cosine (RC) Pulse Shaper. 
72<a href="#_details">More...</a>
73<p>
74<code>#include &lt;<a class="el" href="pulse__shape_8h-source.html">pulse_shape.h</a>&gt;</code>
75<p>
76
77<p>
78<a href="classitpp_1_1Raised__Cosine-members.html">List of all members.</a><table border="0" cellpadding="0" cellspacing="0">
79<tr><td></td></tr>
80<tr><td colspan="2"><br><h2>Public Member Functions</h2></td></tr>
81<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="153c6ae26e19dab3fb07fed0afac53c0"></a><!-- doxytag: member="itpp::Raised_Cosine::Raised_Cosine" ref="153c6ae26e19dab3fb07fed0afac53c0" args="()" -->
82&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Raised__Cosine.html#153c6ae26e19dab3fb07fed0afac53c0">Raised_Cosine</a> ()</td></tr>
83
84<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Constructor. <br></td></tr>
85<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="46d57402d014f22476ed38bfc6ad618d"></a><!-- doxytag: member="itpp::Raised_Cosine::Raised_Cosine" ref="46d57402d014f22476ed38bfc6ad618d" args="(double roll_off, int filter_length=6, int upsampling_factor=8)" -->
86&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Raised__Cosine.html#46d57402d014f22476ed38bfc6ad618d">Raised_Cosine</a> (double roll_off, int filter_length=6, int <a class="el" href="classitpp_1_1Pulse__Shape.html#0a389c9769f5714a3f0b01039fdfa2fd">upsampling_factor</a>=8)</td></tr>
87
88<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Constructor. <br></td></tr>
89<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="871bbcb278b13fdeaae72c74876d4101"></a><!-- doxytag: member="itpp::Raised_Cosine::~Raised_Cosine" ref="871bbcb278b13fdeaae72c74876d4101" args="()" -->
90virtual&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Raised__Cosine.html#871bbcb278b13fdeaae72c74876d4101">~Raised_Cosine</a> ()</td></tr>
91
92<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Destructor. <br></td></tr>
93<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="e6912fad171506d162aba99e60a7875b"></a><!-- doxytag: member="itpp::Raised_Cosine::set_pulse_shape" ref="e6912fad171506d162aba99e60a7875b" args="(double roll_off_factor, int filter_length=6, int upsampling_factor=8)" -->
94void&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Raised__Cosine.html#e6912fad171506d162aba99e60a7875b">set_pulse_shape</a> (double <a class="el" href="classitpp_1_1Raised__Cosine.html#392677c9e81525f06a1a3e03e5a96cdf">roll_off_factor</a>, int filter_length=6, int <a class="el" href="classitpp_1_1Pulse__Shape.html#0a389c9769f5714a3f0b01039fdfa2fd">upsampling_factor</a>=8)</td></tr>
95
96<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Set pulse shape (roll_off_factor between 0 and 1, filter_length even). <br></td></tr>
97<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="8c9500204ca6ffc2aa66e52bcd378dd2"></a><!-- doxytag: member="itpp::Raised_Cosine::get_roll_off" ref="8c9500204ca6ffc2aa66e52bcd378dd2" args="(void) const " -->
98double&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Raised__Cosine.html#8c9500204ca6ffc2aa66e52bcd378dd2">get_roll_off</a> (void) const </td></tr>
99
100<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Get the roll-off factor. <br></td></tr>
101<tr><td class="memItemLeft" nowrap align="right" valign="top">void&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#038f13f1eab9ae39e29c6c01fac0ac79">set_pulse_shape</a> (const <a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; double &gt; &amp;<a class="el" href="classitpp_1_1Pulse__Shape.html#cd7f0b701f29ad43caf8497eee8aacce">impulse_response</a>, int <a class="el" href="classitpp_1_1Pulse__Shape.html#0a389c9769f5714a3f0b01039fdfa2fd">upsampling_factor</a>)</td></tr>
102
103<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Set the general impulse response of the FIR filter.  <a href="#038f13f1eab9ae39e29c6c01fac0ac79"></a><br></td></tr>
104<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="ac428c5628e3e5dff632b382caaacebe"></a><!-- doxytag: member="itpp::Raised_Cosine::get_pulse_shape" ref="ac428c5628e3e5dff632b382caaacebe" args="(void) const" -->
105<a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; double &gt;&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#ac428c5628e3e5dff632b382caaacebe">get_pulse_shape</a> (void) const</td></tr>
106
107<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Get the pulse shape. <br></td></tr>
108<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="a344853245e5f45984b099e79fa998d5"></a><!-- doxytag: member="itpp::Raised_Cosine::get_upsampling_factor" ref="a344853245e5f45984b099e79fa998d5" args="() const" -->
109int&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#a344853245e5f45984b099e79fa998d5">get_upsampling_factor</a> () const</td></tr>
110
111<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Get the over sampling factor. <br></td></tr>
112<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="7556133cd7fb2ac87f4d34dee30bfc41"></a><!-- doxytag: member="itpp::Raised_Cosine::get_pulse_length" ref="7556133cd7fb2ac87f4d34dee30bfc41" args="() const" -->
113int&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#7556133cd7fb2ac87f4d34dee30bfc41">get_pulse_length</a> () const</td></tr>
114
115<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Get the length of the pulse in number of symbols. <br></td></tr>
116<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="db6d549dc1076d2b8b4163b2078b7694"></a><!-- doxytag: member="itpp::Raised_Cosine::get_filter_length" ref="db6d549dc1076d2b8b4163b2078b7694" args="() const" -->
117int&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#db6d549dc1076d2b8b4163b2078b7694">get_filter_length</a> () const</td></tr>
118
119<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Get the length of the internal FIR filter. <br></td></tr>
120<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="466e1220847c89e090a4bb367962df21"></a><!-- doxytag: member="itpp::Raised_Cosine::shape_symbols" ref="466e1220847c89e090a4bb367962df21" args="(const Vec&lt; T1 &gt; &amp;input, Vec&lt; T1 &gt; &amp;output)" -->
121void&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#466e1220847c89e090a4bb367962df21">shape_symbols</a> (const <a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; T1 &gt; &amp;input, <a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; T1 &gt; &amp;output)</td></tr>
122
123<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Shape the input symbols performing upsampling. <br></td></tr>
124<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="e12e322608d6eecd5b7f2e3c9492c9a0"></a><!-- doxytag: member="itpp::Raised_Cosine::shape_symbols" ref="e12e322608d6eecd5b7f2e3c9492c9a0" args="(const Vec&lt; T1 &gt; &amp;input)" -->
125<a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; T1 &gt;&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#e12e322608d6eecd5b7f2e3c9492c9a0">shape_symbols</a> (const <a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; T1 &gt; &amp;input)</td></tr>
126
127<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Shape the input symbols performing upsampling. <br></td></tr>
128<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="14086d26f13af721df4ae4939f80d331"></a><!-- doxytag: member="itpp::Raised_Cosine::shape_samples" ref="14086d26f13af721df4ae4939f80d331" args="(const Vec&lt; T1 &gt; &amp;input, Vec&lt; T1 &gt; &amp;output)" -->
129void&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#14086d26f13af721df4ae4939f80d331">shape_samples</a> (const <a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; T1 &gt; &amp;input, <a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; T1 &gt; &amp;output)</td></tr>
130
131<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Shape the input samples already upsampled. <br></td></tr>
132<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="0161cf1c884ce1de260df48c82a15aa7"></a><!-- doxytag: member="itpp::Raised_Cosine::shape_samples" ref="0161cf1c884ce1de260df48c82a15aa7" args="(const Vec&lt; T1 &gt; &amp;input)" -->
133<a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; T1 &gt;&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#0161cf1c884ce1de260df48c82a15aa7">shape_samples</a> (const <a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; T1 &gt; &amp;input)</td></tr>
134
135<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Shape the input symbols already upsampled. <br></td></tr>
136<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="f85b84d4d2717ca2ae2170074c735bfa"></a><!-- doxytag: member="itpp::Raised_Cosine::clear" ref="f85b84d4d2717ca2ae2170074c735bfa" args="(void)" -->
137void&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#f85b84d4d2717ca2ae2170074c735bfa">clear</a> (void)</td></tr>
138
139<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Clear internal states. <br></td></tr>
140<tr><td colspan="2"><br><h2>Protected Attributes</h2></td></tr>
141<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="392677c9e81525f06a1a3e03e5a96cdf"></a><!-- doxytag: member="itpp::Raised_Cosine::roll_off_factor" ref="392677c9e81525f06a1a3e03e5a96cdf" args="" -->
142double&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Raised__Cosine.html#392677c9e81525f06a1a3e03e5a96cdf">roll_off_factor</a></td></tr>
143
144<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">The roll off factor (i.e. alpha). <br></td></tr>
145<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="cd7f0b701f29ad43caf8497eee8aacce"></a><!-- doxytag: member="itpp::Raised_Cosine::impulse_response" ref="cd7f0b701f29ad43caf8497eee8aacce" args="" -->
146<a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; double &gt;&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#cd7f0b701f29ad43caf8497eee8aacce">impulse_response</a></td></tr>
147
148<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">The impulse resounse of the pulse shaping filter. <br></td></tr>
149<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="5dcd026bd37e73f910f2c5d6c1120d41"></a><!-- doxytag: member="itpp::Raised_Cosine::shaping_filter" ref="5dcd026bd37e73f910f2c5d6c1120d41" args="" -->
150<a class="el" href="classitpp_1_1MA__Filter.html">MA_Filter</a>&lt; T1, double, T1 &gt;&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#5dcd026bd37e73f910f2c5d6c1120d41">shaping_filter</a></td></tr>
151
152<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">The pulse shaping filter. <br></td></tr>
153<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="adc84feb7843931d28b69b03595c47f9"></a><!-- doxytag: member="itpp::Raised_Cosine::pulse_length" ref="adc84feb7843931d28b69b03595c47f9" args="" -->
154int&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#adc84feb7843931d28b69b03595c47f9">pulse_length</a></td></tr>
155
156<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Length in symbols. <br></td></tr>
157<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="0a389c9769f5714a3f0b01039fdfa2fd"></a><!-- doxytag: member="itpp::Raised_Cosine::upsampling_factor" ref="0a389c9769f5714a3f0b01039fdfa2fd" args="" -->
158int&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#0a389c9769f5714a3f0b01039fdfa2fd">upsampling_factor</a></td></tr>
159
160<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Samples per input symbol. <br></td></tr>
161<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="f649289d3f21befa740b7462520c2bc7"></a><!-- doxytag: member="itpp::Raised_Cosine::setup_done" ref="f649289d3f21befa740b7462520c2bc7" args="" -->
162bool&nbsp;</td><td class="memItemRight" valign="bottom"><a class="el" href="classitpp_1_1Pulse__Shape.html#f649289d3f21befa740b7462520c2bc7">setup_done</a></td></tr>
163
164<tr><td class="mdescLeft">&nbsp;</td><td class="mdescRight">Ensures that setup is called before any other member function. <br></td></tr>
165</table>
166<hr><a name="_details"></a><h2>Detailed Description</h2>
167<h3>template&lt;class T1&gt;<br>
168 class itpp::Raised_Cosine&lt; T1 &gt;</h3>
169
170Raised Cosine (RC) Pulse Shaper.
171<p>
172Upsamples and shapes symbols as raised cosine pulses with a given roll-off factor <img class="formulaInl" alt="$ \alpha $" src="form_304.png">. The raised cosine pulse shape is defined as: <p class="formulaDsp">
173<img class="formulaDsp" alt="\[ p(t) = \frac{\sin(\pi t / T)}{\pi t / T} \frac{\cos(\alpha \pi t / T)}{1 - (2 \alpha t / T)^2} \]" src="form_305.png">
174<p>
175 For more details see e.g. Lee &amp; Messerschmitt, p. 190. Observe that the shaping is done with a FIR filter where the size is given by <em>filter_length</em> * <em>over_sample_factor</em> + 1. The first samples in the output will therefore be zero or small before the memory of the filter is filled.<p>
176What is important, when using RC shaping in a transmission system with the AWGN channel, the mean power of the output samples is not normalised, so the channel noise variance (or shaped signal) should be scaled appropriately.<p>
177The class is templated as follows: <code>T1</code> is the type of the input and the output samples. An example of usage is:<p>
178<div class="fragment"><pre class="fragment"><span class="preprocessor">  #include "<a class="code" href="itcomm_8h.html" title="Include file for the IT++ communications module.">itpp/itcomm.h</a>"</span>
179
180  Raised_Cosine&lt;double&gt; rc(0.5, 6, 8);
181  BPSK bpsk;
182  vec symbols, samples;
183
184  symbols = bpsk.modulate_bits(<a class="code" href="group__randgen.html#g5aa06887cf1fd3301b040987924068f0" title="Generates a random bit (equally likely 0s and 1s).">randb</a>(20));
185  samples = rc.shape_symbols(symbols);
186</pre></div> <hr><h2>Member Function Documentation</h2>
187<a class="anchor" name="038f13f1eab9ae39e29c6c01fac0ac79"></a><!-- doxytag: member="itpp::Raised_Cosine::set_pulse_shape" ref="038f13f1eab9ae39e29c6c01fac0ac79" args="(const Vec&lt; double &gt; &amp;impulse_response, int upsampling_factor)" -->
188<div class="memitem">
189<div class="memproto">
190      <table class="memname">
191        <tr>
192          <td class="memname">void <a class="el" href="classitpp_1_1Pulse__Shape.html">itpp::Pulse_Shape</a>&lt; T1 , double , T1  &gt;::set_pulse_shape           </td>
193          <td>(</td>
194          <td class="paramtype">const <a class="el" href="classitpp_1_1Vec.html">Vec</a>&lt; double  &gt; &amp;&nbsp;</td>
195          <td class="paramname"> <em>impulse_response</em>, </td>
196        </tr>
197        <tr>
198          <td class="paramkey"></td>
199          <td></td>
200          <td class="paramtype">int&nbsp;</td>
201          <td class="paramname"> <em>upsampling_factor</em></td><td>&nbsp;</td>
202        </tr>
203        <tr>
204          <td></td>
205          <td>)</td>
206          <td></td><td></td><td><code> [inherited]</code></td>
207        </tr>
208      </table>
209</div>
210<div class="memdoc">
211
212<p>
213Set the general impulse response of the FIR filter.
214<p>
215Observe that the pulse shape must have a duration of an integer number of symbols. Thus the length of the impulse response-1 modulo over sampling is an integer.
216</div>
217</div><p>
218<hr>The documentation for this class was generated from the following file:<ul>
219<li><a class="el" href="pulse__shape_8h-source.html">pulse_shape.h</a></ul>
220</div>
221<hr size="1"><address style="text-align: right;"><small>Generated on Tue Jun 2 10:02:19 2009 for mixpp by&nbsp;
222<a href="http://www.doxygen.org/index.html">
223<img src="doxygen.png" alt="doxygen" align="middle" border="0"></a> 1.5.8 </small></address>
224</body>
225</html>
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