IEEE COMMUNICATIONS LETTERS, vol. 12, no. 3, page. 182 - 184, 2008-03
IEEE COMMUNICATIONS LETTERS, vol. 11, no. 12, page. 928 - 930, 2007-12
IEICE TRANSACTIONS ON COMMUNICATIONS, vol. E90-B, no. 11, page. 3208 - 3215, 2007-11
IEEE COMMUNICATIONS LETTERS, vol. 11, no. 1, page. 28 - 30, 2007-01