The increasing demand for capacity has been driving the wireless communication standards
to provide support to the coexistence of macro and small cells. The backhaul, which
is the link between the radio access network and the backbone, is of particular interest
due to the many involved technical challenges on keeping up with the user demand for
bandwidth. Line-of-sight microwave radio and optical fiber are the preferred choices and
widely adopted for the mobile backhaul (MBH) of macrocells. However, in many situations
of practical interest, both options are not feasible due to cost and logistics. This
work evaluates the backhaul of small cells, focusing on the adoption of copper pairs. Opnet
was also used to evaluate copper MBH requirements in specific scenarios taking into
consideration QoS provisioning. Assuming traffic demands for LTE and LTE-Advanced,
VDSL2 and G.fast technologies are evaluated and the results show that even with a heavy
load of video, these technologies can accommodate the small cell MBH traffic. VDSL2
is capable of delivering the required data rates for LTE small cell scenarios but not if
considered LTE-Advanced traffic. Otherwise, if considered G.fast data rates, backhaul
traffic for LTE-Advanced small cells can still be delivered by xDSL technology with QoS
guaranteed. Also, this work enables the implementation of heterogeneous access networks
scenarios considering LTE NLOS out-of-band backhaul. A solution of LTE backhaul
implementation in OPNET is proposed and simulations are performed to validate such
solution as a QoS-aware LTE Backhaul for WiFi and LTE radio access technologies.
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