1. Department of Information and Communications Engineering, Chosun University, No. 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea
2. Department of Radio Mobile Communications Engineering, Honam University, No. 330 Eodeungno, Gwangsan-gu, Gwangju 506-714, Republic of Korea
3. Department of Computer Science and Engineering, Chosun University, No. 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea