Heterogeneous Backhaul Networks Research Articles

Utility-Based Wireless Routing Algorithm for Massive MIMO Heterogeneous Networks

With the development of 5G communication, massive multiple input multiple output (MIMO) technology is getting more and more attention. Massive MIMO uses a large amount of simultaneous transmitting and receiving antennas to reduce power consumption and raise the level of transmission quality. Meanwhile, the diversification of user equipment (UE) in the 5G environment also makes heterogeneous networks (HetNets) more prevalent. HetNets allow UE of different network standards to access small cells, while the base stations of small cells access a macro base station (BS) to form a multihop wireless heterogeneous backhaul network. However, how to effectively combine these two technologies by efficiently allocating the antennas of each BS during the route construction process of heterogeneous wireless backhaul networks is still an important issue that is yet to be solved. In this paper, we propose an algorithm called preallocated sequential routing (PSR). Based on the links’ channel conditions and the available antennas and location of BSs, it builds a wireless heterogeneous network backhaul topology and adjusts each link’s transmitting and receiving antennas to maximize total utility. Simulation results showed that the proposed algorithm significantly improved the overall utility and the utility of the outer area of heterogeneous networks.

A low complexity mechanism for congestion notification in rural IPSec‐enabled heterogeneous backhaul networks

SummaryManagement in wireless backhaul networks is a challenging task, especially in rural and isolated environments. In these scenarios, the backhaul network usually consists of a set of heterogeneous wireless links that provide limited and variable bandwidth to the access networks, often 3G/4G small cells. Because of the highly constrained nature of this type of backhaul network, intelligent and joint management in both the backhaul network and the access network is crucial in order to avoid performance degradation caused by traffic congestion. In order to avoid the saturation in the backhaul network, access networks should consider the backhaul state when taking decisions in the admission control and scheduling procedures. However, no standardized mechanisms currently exist for sharing management information between both networks. In this work, we propose to use the Explicit Congestion Notification (ECN) bit in the outer IP headers present in the Iuh 3GPP IPSec‐enabled interfaces in order to notify the backhaul congestion state to the access network. We analyze for the referred scenario, compatibility and security details, validating our approach by running numerically simulations and implementing the notification mechanism. Our low complexity approach offers 2% accuracy and backhaul update latency lower than 10 ms during 80% of the time, which makes the solution appropriate for admission control and scheduling intervals in small cells.

Backhauling 5G small cells: A radio resource management perspective

Developing efficient backhauling solutions for small cells is considered as one of the most significant challenges in the rollout of the upcoming 5G cellular systems where massive numbers of small cells will be deployed. In this article, we first review small cell evolutions and the consequent radio access network architecture evolution toward heterogeneity and centralized baseband processing. The backhaul solution, which is mainly determined by the availability of existing backhaul infrastructures and service demand, will lead to a heterogeneous backhaul network architecture. Radio resource management issues including cell association, and interference management and scheduling with inter-node coordination, as well as how they are related to backhaul solutions are discussed. Based on the existing RRM solutions and their limitations in multi-tier 5G systems with heterogeneous backhaul network architecture, backhaul- aware RRM strategies are envisioned. Results from a simple case study of joint cell association and bandwidth allocation with a massive MIMO-based in-band wireless backhauling framework are presented to demonstrate the performance gain with backhaul-aware RRM in a multi-tier cellular RAN. Several related open research issues are highlighted, and possible solution approaches are briefly discussed.

面向工业监控应用的广域异构无线网络端到端时延分析

With the development of wireless communication, the wireless communication technologies based on WirelessHART, WIA-PA, and ZigBee are used widely in the industrial control field. However, owing to the con-straint of capital, technology, equipment, etc., diverse network technologies have long coexisted. Delay analysis is an effective method for detecting real-time network properties in the network design phase. Currently, there is no particular method of analyzing end-to-end transmission delay in wide-area industrial heterogeneous networks. Consequently, based on wide-area heterogeneous backhaul networks with industrial control applications, end-toend delay in wide-area heterogeneous environments, including IEEE 802.11 long-distance WIFI, WirelessHART, ZigBee, and WIA-PA, is analyzed theoretically and verified experimentally. These comparative experiments show that, when the node number of an 802.11 long-distance WIFI backhaul network is greater than 25, and the data aggregation period of the gateway is less than 30 ms, the pessimism ratio is guaranteed to be within 2.3 in the network for ZigBee and within 1.5 for others. The rationale and validity of the method are proved.

Cloud technologies for flexible 5G radio access networks

The evolution toward 5G mobile networks will be characterized by an increasing number of wireless devices, increasing device and service complexity, and the requirement to access mobile services ubiquitously. Two key enablers will allow the realization of the vision of 5G: very dense deployments and centralized processing. This article discusses the challenges and requirements in the design of 5G mobile networks based on these two key enablers. It discusses how cloud technologies and flexible functionality assignment in radio access networks enable network densification and centralized operation of the radio access network over heterogeneous backhaul networks. The article describes the fundamental concepts, shows how to evolve the 3GPP LTE a