Coherence Diversity in Time and Frequency

In practice, wireless nodes may have different mobility and/or different scattering environment leading to disparity in coherence time and/or coherence bandwidth. Coherence diversity, as a novel source of gain, exploits fading condition disparity of different nodes to provide gain. Downlink transmission for two wireless nodes is considered in three scenarios of fading conditions disparity: in coherence time, in coherence bandwidth, and in both coherence time and coherence bandwidth. Coherence diversity gain is calculated in the three scenarios using product superposition transmission, and furthermore, numerical simulations are presented to demonstrate the gains.