Philip Hunter /
Originally featured on BroadcastEngineering.com
Call for EU to make virgin spectrum available for mobile backhaul
European mobile operators should start provisioning extra backhaul at the start of 4G LTE (Long Term Evolution) deployments rather than bolt it on afterwards. At the same time, they should make extensive use of microwave for their backhaul except in urban areas where they can justify the cost of digging up the ground to install fiber. This is the message from French microwave technology vendor Bluwan, which clearly has a vested interest in promoting this as a solution for backhaul. But, the company is right to warn operators that without extensive investment in backhaul, 4G mobile services based on LTE will fall flat on their face.
LTE appears now to be the technology of choice for emerging 4G services, increasing the amount of access bandwidth by up to 10 times. Unless there is a corresponding increase in backhaul capacity, mobile operators will not be able to carry this extra traffic back into their networks. In some cases, copper twisted pairs provided by a telecommunications carrier are used for backhaul, but even given technical improvements in mitigation of crosstalk on these, they will often fail to meet future backhaul needs. Fiber is the perfect medium, but the cost of deploying it can only be justified in more densely populated areas. This will leave microwave fulfilling a growing proportion of backhaul requirements as copper is decommissioned, rising from the current 55 percent to 70 percent in 2014, according to Bluwan.
While this may be overstating the rise, microwave is certainly going to remain an important part of the mix, and Bluwan is probably right in its assertion that of the two alternative configuration options, Point-to-Multipoint (PTMP) will be superior to Point-to-Point (P2P). This will especially be the case for broadcast TV services, where the ability of PTMP to deliver content to multiple base stations at once will be more economical.
Meanwhile Bluwan is lobbying European regulators to allocate spectrum in the 40GHz region as this can be available for backhaul and will enable operators to hit the ground running with robust LTE services that have enough core capacity to meet the anticipated surge in demand that 4G will bring.v