Ergodic Capacity of D2D Underlay Communication using MC-CDMA

Abstract

Device to device (D2D) communication that underlay conventional cellular networks can increase their spectrum utilization. However, sinceD2Dpairs share the frequency band with cellular users, interference between these two network tiers can become a major performance bottleneck. In this scenario, use of a spread spectrum technique can be a good choice for D2D communication, due to its inherent interference mitigation capability. In this work, we analyze the achievable ergodic capacity for a D2D user pair that uses multi-carrier code divisionmultiple access (MC-CDMA). Interference from both cellular users and other D2D pairs is considered under Rayleigh faded links and carrier frequency offset. Our derived expression requires a single integration and gives a tight lower bound to achievable ergodic capacity.