Asymptotically Optimum Multiuser Decision Feedback Detection

<body background="_themes/varhome/hadamard.gif" bgcolor="#FFFFFF" text="#000000" link="#3366CC" vlink="#666666" alink="#FF3300"><font face="trebuchet ms, arial, helvetica">  <p> <a href="http://dsp.colorado.edu"><img src="images/dsplogo.gif" alt="dsplogo.gif (3930 bytes)" border="0" align="middle" WIDTH="153" HEIGHT="50"></a> <a href="http://ece-www.colorado.edu"><img src="_borders/ecebutton.gif" alt="ECE Homepage" align="middle" border="0" WIDTH="63" HEIGHT="56"></a> <a href="http://www.colorado.edu"><img src="_borders/colorado.jpg" alt="University Homepage" align="middle" border="0" WIDTH="91" HEIGHT="54"></a></p> <div align="left"> </font><table border="0" cellpadding="5" cellspacing="0"> <tr> <td width="150" valign="top" align="center"><font face="trebuchet ms, arial, helvetica"><strong><small><small>This paper falls into the Research Interests:</small></small></strong><p> </p> <p><small><a href="res-inter.htm" target="main"><strong><small>Coherent Interference Cancellation</small></strong></a></small></p> <p><img src="images/blank.gif" width="150" height="20" alt></font></td> <td valign="top" align="left" width="750"><font face="trebuchet ms, arial, helvetica"><h2><font color="#CC6666">Asymptotically Optimum Multiuser Decision Feedback Detection</font></h2> <p>M. K. Varanasi, Proc. 1997 Intl Symp. Inform. Th, pp. 275, Ulm, Germany, June-July 1997</p> <p>The optimum decision feedback multiuser detection rule was obtained in <a href="#[1]" target="_self">[1]</a> for the joint detection of K simultaneously transmitting users in a synchronous Gaussian Correlated Waveform Multiple Access (CWMA) channel. The measure of optimality considered there was the asymptotic symmetric (worst-case over users) effective energy. The resulting optimum decision feedback detector (ODFD) is characterized by a feedforward-feedback matrix pair and requires K additions and K multiplications per user after matched filtering for its implementation. In this paper, it is shown that in addition to its optimality in asymptotic symmetric effective energy, the ODFD can, under certain conditions, achieve optimum asymptotic effective energy for every user, thereby matching the asymptotic efficiency performance of the exponentially complex maximum likelihood detector for all users simultaneously. In proving this result, it is not assumed that interference cancellation is perfect. </p> <ol> <a name="[1]" target="_top"> <li></a> <p>M. K. Varanasi, "<a target="_top" href="pvarciss9703-f.htm">Optimizing Symmetric Energy and Permuting Users for Decision Feedback Multiuser detection to User-Wise Outperform Linear Multiuser Detection</a>," Proc of the Conf. Inform. Sciences and Systems, pp. 492-497, Johns Hopkins University, March 1997. </p> </li> </ol> <p><strong><small>This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.</small></strong></p> <p><strong><small>© 2000 <a href="http://www.ieee.org/">IEEE</a>. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the <a href="http://www.ieee.org/">IEEE</a>.</small></strong></p> </font></td> </tr> </table><font face="trebuchet ms, arial, helvetica"> </div> <p><small><small>Last modified: 2000-03-31T23:03</small></small></p>  </font></body>