  In this paper, we propose light-emitting diode (LED) selection that can be
applied not only to the conventional Multiple-Input Multiple-Output (MIMO)
case, but also to a larger MIMO configuration of generalized LED index
modulation (GLIM) system with optical orthogonal frequency division
multiplexing (OFDM) in visible light communication (VLC). Moreover, we derive a
simplified implementation of the maximum a posteriori (MAP) detector when the
number of LEDs is an even number larger than four. Simulation results show that
the performance of MAP and LED selection is better than other detection
algorithms for larger even numbers of LEDs and conventional GLIM for $4\times4$
transmission, respectively.
