Deployment analysis and optimization of Macro-Pico heterogeneous networks in LTE-A system

Heterogeneous Networks have been introduced in the LTE-Advanced system by 3GPP to improve the overall network capacity. However, for Macro-Pico scenario, the coexistence of macro eNodeBs (MeNBs) and additional low power nodes (LPNs) may lead to much higher interference, which requires intensive investigation on pico eNodeB (PeNB) deployment issues. On the other hand, Cell Range Extension (CRE) is a promising technique to utilize the LPN resources more effectively and improve the cell edge performance, where the bias value should be properly set. In this paper, the main factors affecting the system performance are studied first. Then a system-level simulation test-bed is established to provide the performance of Macro-Pico network, based on which the key issues for pico cell deployment are investigated. Results show that if good principles are applied in PeNB deployment, i.e. large macro-to-pico distances, relatively high transmit power, high deployment density and an optimal value of CRE bias, the gain of introducing pico cells could be significantly enhanced in terms of both cell edge performance and the overall system throughput.