  We propose a new secure transmission scheme which uses directional modulation
(DM) with artificial noise and is aided by the intelligent reflecting surface
(IRS). Specifically, the direct path and IRS-enabled reflect path carry the
same confidential signal and thus can be coherently added at the desired
position to maximize the total received power, while the received signals at
other positions are distorted. We derive a closed-form expression for the
secrecy rate achieved by the proposed scheme. Using simulation results, we show
that the proposed scheme can achieve two-dimensional secure transmission at a
specific position. Also, its performance advantage over the conventional DM
scheme becomes more pronounced as the number of reflecting elements at the IRS
increases.
