Advantages and Disadvantages of OFDM
1.Makes efficient use of the spectrum by allowing overlap.
2.By dividing the channel into narrowband flat fading subchannels, OFDM is more resistant
to frequency selective fading than single carrier systems are.
3.Eliminates ISI and IFI through use of a cyclic prefix.
4.Using adequate channel coding and interleaving one can recover symbols lost due to the
frequency selectivity of the channel.
5.Channel equalization becomes simpler than by using adaptive equalization techniques with
single carrier systems.
6.It is possible to use maximum likelihood decoding with reasonable complexity.
7.OFDM is computationally efficient by using FFT techniques to implement the modulation
and demodulation functions.
8.Is less sensitive to sample timing offsets than single carrier systems are.
9.Provides good protection against cochannel interference and impulsive parasitic noise.
1.The OFDM signal has a noise like amplitude with a very large dynamic range, therefore it
requires RF power amplifiers with a high peak to average power ratio.
2.It is more sensitive to carrier frequency offset and drift than single carrier systems are due
to leakage of the DFT.