Advancing Active Power Control Technique for Interference Mitigation in Macro-Femtocellular Networks.



Femtocells are strategically deployed alongside existing Macrocells to create a Macro-Femto heterogeneous network (HetNet), aiming to enhance cellular network capacity and throughput performance while reducing the cost of deploying expensive macrocell nodes. Nevertheless, HetNet encounters a significant challenge of cross-tier and co-tier interference, which hampers its optimal performance, particularly as the network capacity expands. As 5G technologies emerge, this interference issue becomes even more critical. To address this challenge and sustain an efficient HetNet, effective interference mitigation techniques are essential.

In this study, we investigated the implementation of a power control technique to alleviate the impact of interference in both Downlink and Uplink scenarios of the 5G non-stand-alone (NSA) architecture of the Macro-Femto HetNet. We developed an enhanced active power control (EAPC) technique by combining the extended attenuation factor path loss model with Active Power Control (APC) and Power Control 1 (PC1) techniques. The attenuation factor model was extended to incorporate floor attenuation and wall factor, which significantly improved the accuracy of femtocell path loss computation.

Moreover, the EAPC technique adopted a unique step power value of 0.5 dB to optimize transmit power, thereby maximizing power efficiency and reducing interference. Comparing the hybridized EAPC approach with individual implementations of APC and PC1, we observed significant performance improvements. The EAPC technique yielded 65% and 37% higher throughput for Home User Equipment (HUE) compared to APC and PC1, respectively. Additionally, the Macro User Equipment (MUE) throughput was 37% and 21% higher, the throughput of the femtocell node (Hen-gNB) was 41% and 63% higher, and the throughput of the macrocell node (en-gNB) was 69% and 25% higher when using EAPC, as compared to APC and PC1.

Furthermore, the EAPC technique exhibited substantial energy savings. In comparison with APC and PC1, EAPC reduced the Home User Equipment (HUE) battery energy consumption by 65% and 40%, respectively. Additionally, it saved 38% and 42% of Macro User Equipment (MUE) battery energy, as well as 54% and 22% of Hen-gNB energy. While EAPC achieved a 21% reduction in en-gNB energy consumption when compared to APC, it exhibited a limitation of only 8% compared to PC1.

In conclusion, the proposed EAPC technique demonstrates superior interference mitigation capabilities and considerable energy efficiency improvements within the 5G non-stand-alone Macro-Femto HetNet. Its implementation holds promise for sustaining larger and more efficient HetNets as cellular networks continue to evolve.

Advancing Active Power Control Technique for Interference Mitigation in Macro-Femtocellular Networks.  GET MORE, ACTUARIAL SCIENCE PROJECT TOPICS AND MATERIALS