In this paper, we analyze the BER performance of our proposed GCM method under the channel model provided by the IEEE 802.15.7r1 and compare the performance with the intensity based modulations. Through simulations, it will be shown that GCM based performance is generally superior to that of intensity based PAM in most indoor positions. GCM will be applied in wide range of VLC applications as an alternative to the indoor wireless communication to enhance the performance.