Feasibility of capacity enhancement of public safety LTE using device-to-device communication

Public safety networks are desired to meet increasing demands for sharing images or videos among first responders and incident commanders. Long term evolution (LTE) is considered a candidate to achieve such broadband services. Base stations (BSs) of public safety LTE will probably be deployed less densely than those of commercial LTE to enable lower capital expenditures related to BS deployment. Although the traffic created by public safety users at regular hours is low, base stations also need to accommodate suddenly increasing traffic due to disasters or big sporting events. Device-to-Device (D2D) communication has the potential to solve the problem owing to some gains of direct communication. This paper looks into the feasibility of capacity enhancement for high traffic situations through the introduction of D2D communication. System level simulation results reveal that resource sharing among D2D users is essential to achieve higher-capacity communication. Compared to an LTE system without D2D communication, it can achieve 3.8 times higher system throughput even if simple resource management for D2D communication is applied.