To cooperate with increasing traffic due to high data rate video transmission revolutionary changes needed in the existing wireless networks. In 5th generation wireless networks mainly concentrate on user requirements of high data rate, speed, and higher coverage area. This paper mainly concentrate on physical layer operations. Modulation and coding operation performed in physical layer. To improve the performance of physical layer new technology introduced such that adaptive modulation and coding (AMC). Depending upon the CQI value modulation and coding adapted automatically so spectral efficiency will improved more and avoiding the wastage of resources but in the previous case fixed modulation scheme only used. Channel quality indicator (CQI) Measured based upon noise, receiver performance, interference, channel condition.