Dual Connectivity in Backhaul-Limited Massive-MIMO HetNets: User Association and Power Allocation

Abstract

With dual connectivity, a mobile user can be served by a macro base station (MBS) and a pico base station (PBS) simultaneously. In this paper, we address the problem of optimizing user-PBS association and power allocation in the uplink such that the network can serve the users' demand at the minimum cost, where the PBSs are subject to backhaul capacity limitations and minimum rate requirements of users. We show that this non-convex problem can be formulated as a signomial geometric programming (SGP) whose solution can be found by solving a series of geometric programming (GP) problems. Simulation results are provided to demonstrate traffic offloading trend to PBSs for different cost and backhaul capacity settings, confirming the effectiveness of the proposed iterative algorithm. They also show that the output of the proposed algorithm closely matches the global optimal solution with affordable complexity.

User association and resource allocation in 5G (AURA-5G): A joint optimization framework

“…Note that, in [8], for DC, the authors consider that a UE can be associated with an MC and an SC that is within the coverage of this selected MC. Next, the authors of [29] consider the problem of user association for the uplink with power allocation optimization being another objective. They consider user minimum rate requirements as well as backhaul limitations at the pico BSs as the constraints and aim to find an association that reduces the overall cost for the network while demands of all the users are satisfied.…”

Cross-Tier Dual-Connectivity Designs of Three-Tier Hetnets With Decoupled Uplink/Downlink and Global Coverage Performance Evaluation

“…Another set of relative research works includes [22]- [27], where the DC was used. Liu et al [23], Wang et al [24] have evaluated the achievable performance gain by DC. Although in 3GPP Release 12 [25], DUDA using DC was limited to inter-frequency deployments, the work [26] pointed out that the later Release may add support for intra-frequency band (or in-band) deployments.…”

Conditional dual‐connectivity decoupling design framework for OMA and NOMA heterogeneous networks and performance comparison

“…11.1 Proof of (22) and (23) Considering the event R P − OM 1 ⩽ r is the event r OM ⩽ r, given the typical UE's UL primary association with the M-tier, by using the similar argument as in (10) r OP , the second term of the right hand in (21) can be calculated as (63). Hence, by substituting (62) and (63) into (20) and 21, we obtain the CDFs F R P − OM…”

“…DC allows users to be simultaneously served by two different network points, the primary access point and secondary access point, which is a significant distinction from traditional single connectivity. Therefore, integrating DUDA and DC is a promising candidate for the improvement of robustness [22][23][24]. With this consideration, Lema et al [25] focused on the design of DUDA in DC-mode HetNet, where authors considered a two-tier HetNet with the joint application of DUDA and DC.…”

“…Total average UL CPs' comparison between DUDA and CUDA with α P = 0.65 (a) NOMA mode (b) OMA mode Total UL average SE comparison between DUDA and CUDA with α P = 0.65 (a) NOMA mode (b) OMA mode and F R S − OF 1 r , respectively. Then, taking the derivations of F R P − OM 1 r and F R S − OF leads to(22) and(23).…”