This paper proposes a low-complexity scheduling algorithm with opportunistic channel state feedback using zero-forcing dirty paper coding (ZF-DPC) or zero-forcing (ZF). Whereas some existing schemes suffer a delay to update the serving users, the proposed algorithm continues to update the serving users immediately at each opportunistic channel feedback. Due to this dynamic serving user adaptati...

Several researchers have recently explored various graph parameters that can or cannot be characterized by the spectrum of a matrix associated with graph. In this paper, we show several NP-hard zero forcing numbers are not spectra types matrices particular, consider standard forcing, positive semidefinite and skew provide constructions infinite families pairs cospectral graphs, which different ...