Analytical Evaluation of Fractional Frequency Reuse for OFDMA Cellular Networks

Abstract

Fractional frequency reuse (FFR) is an interference management technique well-suited to OFDMAbased cellular networks wherein the cells are partitioned into spatial regions with different frequency reuse factors. To date, FFR techniques have been typically been evaluated through system-level simulations using a hexagonal grid for the base station locations. This paper instead focuses on analytically evaluating the two main types of FFR deployments -Strict FFR and Soft Frequency Reuse (SFR) -using a Poisson point process to model the base station locations. The results are compared with the standard grid model and an actual urban deployment. Under reasonable special cases for modern cellular networks, our results reduce to simple closed-form expressions, which provide insight into system design guidelines and the relative merits of Strict FFR, SFR, universal reuse, and fixed frequency reuse. We observe that FFR provides an increase in the sum-rate as well as the well-known benefit of improved coverage for cell-edge users. Finally, a SINR-proportional resource allocation strategy is proposed based on the analytical expressions, showing that Strict FFR provides greater overall network throughput at low traffic loads, while SFR better balances the requirements of interference reduction and resource efficiency when the traffic load is high.

Dynamic Fractional Frequency Reuse Diversity Design for Intercell Interference Mitigation in Nonorthogonal Multiple Access Multicellular Networks

“…As previously discussed, FFR is more effective in minimizing ICI because of its isolation of channels for edge and center users, so it will be used in the proposed solution instead of SFR [2,33]. SFR takes precedence over FFR (or strict FFR) due to its greater resource efficiency due to the sharing of resources amongst CE and CC users [38]. Diversity in frequency reuse is used for the minimization of ICI and different reuse factors are used for center and edge zones of cells [37][38][39].…”

“…SFR takes precedence over FFR (or strict FFR) due to its greater resource efficiency due to the sharing of resources amongst CE and CC users [38]. Diversity in frequency reuse is used for the minimization of ICI and different reuse factors are used for center and edge zones of cells [37][38][39]. Frequency isolation is established by using a higher reuse factor in edge zones of cells in a multicellular environment.…”

SC-FDMA-based resource allocation and power control scheme for D2D communication using LTE-A uplink resource

“…According to strict FFR [38,39], the center zone has a frequency reuse factor (FRF) of 1 while the outer zones have FRF of N. Figure 2a,b,c shows the deployment of a network using strict FFR with N = 3 at the outer zone. It can be seen from the figures that DUEs in the center zone reuse the frequency of the outer zone of the neighboring cells.…”

Performance Evaluation of Joint Power and Frequency-Domain Intercell Interference Coordination in Heterogeneous Networks

“…In the method, a protected band is defined within the overall system bandwidth, which is exclusively used by only pico BSs, in order to alleviate the macro-to-pico interference [1-3, 8, 9]. In the remaining frequency band, which is called the non-protected band in this paper, we employ fractional frequency reuse (FFR) at the macro BSs so that the macro-to-macro ICIC is achieved [10][11][12][13][14]. Furthermore, in [15], the bandwidth allocation to the protected band and the transmission power of the macro BSs are jointly and adaptively controlled from the viewpoint of proportional fairness (PF) [16,17].…”

“…Furthermore, in [15], the bandwidth allocation to the protected band and the transmission power of the macro BSs are jointly and adaptively controlled from the viewpoint of proportional fairness (PF) [16,17]. More specifically, we employed adaptive power control for the macro BSs assuming frequency usage based on soft FFR (SFR) [10]. The proposed method jointly optimizes the cell association (the decision regarding which BS serves which users), the bandwidth allocation to the protected band, control of the total transmission power at the macro BS, and the power splitting among different frequency blocks in SFR at the macro BS.…”