All basestations would carry out all of these self-configuration processes. These include macrocell basestations, with their extensive range and soaring antenna towers, picocells, which are smaller and have a more limited range than macrocells, and the newer femtocell basestations that will eventually be installed in homes and small businesses. In fact, these auto-configuration process take on even greater importance as a greater variety of basestation types is installed to optimize the network’s coverage and capacity.

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Until recently, the mainstay type of basestation for the wireless industry has always been the macrocell. But moving forward, operators will surely deploy the type of basestation that maximizes coverage and service quality indoors and out and, at the same time, minimizes both operational and procurement costs.

The smaller picocells will dot the wireless landscape, providing coverage in nooks and crannies that may not receive proper coverage from larger macrocells. The new femtocell also will provide better coverage inside homes and businesses, which should accelerate the already ongoing trend of wireless services replacing traditional wireline service.

In particular, auto-configuration will be an imperative feature of femtocell basestations if providers hope to control deployment and provisioning costs. A femtocell that can automatically configure its cell’s physical ID and construct its neighbor relation table will be a big step in the direction of plug-and-play capabilities that are needed in SON.

Based on a number of predetermined operational criteria such as energy savings, range requirements, and interference conditions, a SON basestation will begin the self-optimization process once its initial configuration has been completed and it has joined the network. One of the first optimization tasks it will undertake will be to dynamically prune and select the basestations that are on its neighbors list.

In addition, the basestation will begin measuring signals in its environment—its own signals and those emanating from handsets in its range. These measurements will form the basis for the station’s dynamic auto-tuning process, which is intended to optimize the operating state of the basestation at any moment in time. Auto-tuning is a perpetual process that automatically senses spatial and temporal changes in the network and within the basestation’s range, optimizing the station’s predetermined operational criteria.

SON enables systems to switch on a home eNB (home basestation) to increase energy savings for residential and enterprise femtocell users by tracking the mobility of the mobile user from “cell 1” to “cell 2” to the home. Similarly, a SON would switch the home eNB off when mobile users step out of their home or office to cell 4.
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The operating conditions present in a wireless network are constantly in a state of flux. Some changes, like increased call traffic caused by rush hour congestion along a highway, are predictable. But others, such as intermittent failures in network hardware or software, are not. In any case, a SON basestation must be able to launch self-healing procedures appropriate to the conditions currently being encountered. These self-healing measures would allow the service provider to guarantee a certain grade of service/quality of service to subscribers.