  This paper investigates the idea of exploiting interference among the
simultaneous multiuser transmissions in the downlink of multiple antennas
systems. Using symbol level precoding, a new approach towards addressing the
multiuser interference is discussed through jointly utilizing the channel state
information (CSI) and data information (DI). In this direction, the
interference among the data streams is transformed under certain conditions to
useful signal that can improve the signal to interference noise ratio (SINR) of
the downlink transmissions. In this context, new constructive interference
precoding techniques that tackle the transmit power minimization (min power)
with individual SINR constraints at each user's receivers are proposed.
Furthermore, we investigate the CI precoding design under the assumption that
the received MPSK symbol can reside in a relaxed region in order to be
correctly detected.
