  We address the challenge of spectral sharing between a statistical
multiple-input multiple-output (MIMO) radar and an in-band full-duplex (IBFD)
multi-user MIMO (MU-MIMO) communications system operating simultaneously in the
same frequency band. Existing research on joint MIMO-radar-MIMO-communications
(MRMC) systems has limitations, such as focusing on colocated MIMO radars,
half-duplex MIMO communications, single-user scenarios, neglecting practical
constraints, or employing separate transmit/receive units for MRMC coexistence.
This paper, along with companion papers (Part I and III), proposes a
comprehensive MRMC framework that addresses all these challenges. In the
previous companion paper (Part I), we presented signal processing techniques
for a distributed IBFD MRMC system. In this paper, we introduce joint design of
statistical MIMO radar codes, uplink/downlink precoders, and corresponding
receive filters using a novel metric called compounded-and-weighted sum mutual
information. To solve the resulting highly non-convex problem, we employ a
combination of block coordinate descent (BCD) and alternating projection
methods. Numerical experiments show convergence of our algorithm, mitigation of
uplink interference, and stable data rates under varying noise levels, channel
estimate imperfections, and self-interference. The subsequent companion paper
(Part III) extends the discussion to multiple targets and evaluates the
tracking performance of our MRMC system.
