  This letter proposes a novel dual user selection scheme for uplink
transmission with multiple users, where a jamming user and a served user are
jointly selected to improve the secrecy performance. Specifically, the jamming
user transmits jamming signal with a certain rate, so that the base station
(BS) can decode the jamming signal before detecting the secret information
signal. By carefully selecting the jamming user and the served user, it makes
the eavesdropper decode the jamming signal with a low probability meanwhile the
BS can achieve a high receive signal-to-noise ratio (SNR). Therefore, the
uplink transmission achieves the dual secrecy improvement by jamming and
scheduling. It is shown that the proposed scheme can significantly improve the
security of the uplink transmission.
