Communications systems concerted over wireless channels depend on the environment. Communications system can be more
reliable and efficient by properly analyzing wireless channels. Today's most important features are a high data rate and reliable
performance to exploiting viable networks during this new information age. The channel is not time-invariant in wireless
communication, so the received signal exhibits amplitude, phase, and angle variations due to multipath fading. Increasing data
rates and reducing bandwidth make Orthogonal Frequency Division Multiplexing (OFDM) an important component of wireless
communication systems. The OFDM technique uses many carriers very efficiently. With this scheme, interference is robustly
reduced, and fading scenarios are easily accommodated. Analyzing digital modulation schemes requires evaluating link
performance with fading channels. The paper compares channel performance over varying fading environments using a variety
of modulation schemes. We study the BER and SNR properties of the AWGN, Rician fading and Rayleigh fading channels
modulated with BPSK, QPSK, and M-ary QAM.