Daewoo Chung, Hyunseung Choo, Hee Yong Youn
and Seong-Moo Yoo+
School of Information and Communication Engineering
Sungkyunkwan University
Suwon 440-746, Korea
E-mail: {chung, choo, youn}@ece.skku.ac.kr
+Electrical and Computer Engineering Department
The University of Alabama in Huntsville
Huntsville, AL 35899, U.S.A.