Wireless Channel Impairment Mitigation Techniques

Wireless channels cause many types of wireless channel impairments such as noise, path loss, shadowing, and fading, and wireless communication systems should be designed to overcome these wireless channel impairments. This chapter investigates the fundamentals of wireless channel impairment mitigation techniques. Diversity techniques mitigate multipath fading effects and improve the reliability of a signal by utilizing multiple received signals with different characteristics. C. Shannon predicts that it is possible to transmit information without errors over the unreliable channel and an error control coding technique exists to achieve this. Multiple Input Multiple Output (MIMO) techniques are classified into spatial diversity techniques, spatial multiplexing techniques, and beamforming techniques. Due to a time dispersive channel by multipath fading, Inter‐Symbol Interference (ISI) occurs and an equalizer plays an important role in ISI compensation. The Orthogonal Frequency Division Multiplexing (OFDM) system also has many advantages.