System-level simulation of a multilayer broadcast and broadband system

Abstract

Long Term Evolution Advanced (LTE-A) describes the latest evolution of the mobile network standard of the 3rd Generation Partnership Project (3GPP). Cellular wireless communication standards, such as LTE-A, are primarily developed for the content distribution of user specific data via unicast transmissions. The exponential growth in data traffic in mobile networks might require alternative approaches for content distribution in order to relief network cells from load congestion. The 3GPP evolved Multimedia Broadcast Multicast Service (eMBMS) and Single-Cell Point-to-Multipoint (SC-PTM) enable multicast/broadcast transmissions of content as an alternative transmission layer to the unicast transmission layer. SC-PTM and eMBMS rely on the existing Low Tower, Low Power (LTLP) infrastructure of current mobile access networks and utilize the same carrier, effectively reducing the number of resources available for unicast services. The Tower Overlay over LTE-Advanced+ (TOoL+) system was developed by Technische Universitaet Braunschweig and field tested together with partner organizations GatesAir, Rai and TDF. It introduces an additional transmission layer by offloading popular content to a dedicated broadcast carrier transmitted from a High Tower, High Power (HTHP) infrastructure. The associated modifications of the LTE-A standard are indicated by the term ‘LTE-A+’. To evaluate the capabilities of the TOoL+ system in a realistic environment, we integrated the existing broadcast solutions for LTE-A and TOoL+ into the Simulator for Mobile Networks (SiMoNe) environment, a software platform for realistic mobile network simulations on the system level, also developed by Tech-nische Universitaet Braunschweig. In this paper, we present the implementation details and evaluate the impact of the different broadcasting layers on cell loads in a realistic network scenario.