Active Antenna system (AAS)

An active antenna is an antenna that contains active electronic components.remote radio head (RRH) or antenna-integrated radio designs place the Rf module next to the passive antenna to reduce cable losses

Active Antenna system is developed by Nokia Siemens Network (NSN) to reduce network cost and increase network efficiency. It’s a smart antenna and beam is driven by software.

Active Antenna does not need to be merely passive elements. With intelligent integration, active antenna technology transforms traditional antenna to contribute to base station efficiency. This enables operators to significantly increase the capacity and coverage targets set for their network.

Active Antennas are highly flexible and can meet the needs of many scenarios. They also support rising feature complexity including higher-order MIMO and receiver diversity, while retaining a simple and compact form factor.

§  Carrier-specific tilting

§  System-specific tilting

§  Multi-operator network sharing

§  Boosting performance with SON

§  Lower overall site costs

§  Improved network availability

§  Higher energy efficiency and RF performance

§  Reduced network evolution costs

The benefits to be gained include boosted capacity and coverage, higher energy efficiency, lower site rental fees, lower wind loading and reduced investments as new radio technologies come on line and additional spectrum bands become available. As a result,
active antenna systems enable operators to not only cut site costs substantially, but to also more cost effectively meet the dynamic demands of their mobile customers.

It is clear that active antenna systems will bring about a step-change in the evolution of radio networks. Leading the field is the Nokia Siemens Networks Flexi Multiradio Antenna System, which is a vital part of Liquid Net. This radical new architecture helps operators to cost-effectively address unpredictable demand by creating networks that adapt instantly to changing customer needs, using existing capital investments more efficiently and generating entirely new revenue opportunities. It does this by unleashing frozen network capacity into a reservoir of resources that can flow to fulfill demand, wherever and whenever broadband is used.

AAS BENEFITS

The benefits of active antenna architecture over RRH based site architecture are many. First, there is a potential to significantly reduce the site footprint. Second, the distribution of radio functions within the antenna results in built-in redundancy and improved thermal performance, which can result in higher system availability (lower failure rates). Third, distributed transceivers can support a host of advanced electronic beam-tilt features that can enable improvements in network capacity and coverage; hence, it has the potential to lower capital and operational costs. Each of these features shall now be described in the following sections.