  This paper presents an efficient construction of two-dimensional (2D)
complete complementary codes (CCCs) for their modern application as
omnidirectional precoding matrices in massive MIMO systems to attain enhanced
cell coverage. Unlike the traditional 1D CCCs, little progress has been made on
efficient and systematic constructions of the 2D counterpart. In contrast to
the existing recursive constructions with the aid of various sequence
operations, certain 1D seed sequences or 2D arrays, we propose to use 2D
generalized Boolean functions for direct synthesis of 2D CCCs. Simulation
results show that the proposed 2D CCCs appear to be good candidates for
precoding matrices to achieve omnidirectional transmission in massive MIMO
systems.
