ÿþ<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" > <html> <head> <meta http-equiv="Content-Language" content="en-us"> <meta http-equiv="Content-Type" content="text/html; charset=windows-1252"> <meta name="GENERATOR" content="Microsoft FrontPage 4.0"> <meta name="ProgId" content="FrontPage.Editor.Document"> <link rel="stylesheet" href="../style/abstract.css" type="text/css"> <title>Theory of Microwaves Amplification and Generation in Coaxial Ubitrons </title> </head> <body> <table width="90%" align="center" border="0"> <tr> <td width="50%" align="left"><font style="color: navy; font-weight:bold; font-size:larger">ELECTROMAGNETIC PHENOMENA</font></td> <td width="10%" align="center">&nbsp;</td> <td width="40%" align="right"><font style="color: #FF0000; font-weight:bold; font-size:larger">2008, Vol.8, No.1(19) &nbsp;26-39</font></td> </tr> </table> <hr width="90%" align="center" color="black"> <p>&nbsp;</p> PACS &#8470;: 84.30.Jc<br> <h2 align="left">V.A. Balakirev, A.V. Borodkin, Yu.V. Tkach, T.Yu. Yatsenko</h2> <h4> Institute for Electromagnetic Research, <br> POB 10857, Kharkov-61022, <br> Ukraine,Phone: 8-(057)705-19-52,<br> e-mail: <a href="mailto: tkach@iemr.com.ua"> tkach@iemr.com.ua</a> <B></B></h4> <table border="0" width="70%" align="center"> <tr><td><h2><i>Theory of Microwaves Amplification and Generation in Coaxial Ubitrons </i></h2></td></tr> <tr><td><h3>Abstract</h3> <div align="justify"> <p>Results of the theoretical studies addressing microwaves amplification and generation in coaxial Ubitrons with the undulator constructed using permanent circular magnets are presented. Spatial magnetic field structure is designed for a coaxial undulator. High-current relativistic electron beam (REB) transport process in this undulator is considered. Nonlinear theory is constructed for microwaves amplification in the coaxial Ubitron. The efficiency of the Ubitron amplifier is derived. The theory is expanded to consider Ubitron oscillator with an external delayed feedback. Starting currents for this oscillator are determined. Modes of microwave generation are studied for various REB currents. Ñoaxial backward wave Ubitron oscillator driven by a high-current REB is studied. Initial currents of the oscillator are determined. Nonlinear dynamics of microwave generation for various values of the REB current is considered.</p> </div> </td></tr></table> <table align="center" width="100%" style="margin: 1cm, 0cm, 1cm, 0cm"> <tr><td>&nbsp;</td><td> <table border="0" align="right"> <tr><td><font size="+1">Full text:</font></td> <td align="left" width="50">&nbsp;</td></tr> <tr><td><a href="./pdf/balakirev.pdf">Balakirev.pdf (2270K)</a></td> <td>&nbsp;</td> </table> </td></tr> </table> <table align="center" border="0" width="90%"><tr bgcolor="black"><td height="2" style="height:2px"><img src="Picts/pixel_b.gif" alt="" width="90%" height="1" border="0"></td> </tr></table> <div align="center"><a href="index.htm">Back to Contents</a></div> </body> </html>