Ari Hämäläinen

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The paper validates the feasibility of automating the setting of common pilot power in a WCDMA radio network. The pilot automation improves operability of the network and it is implemented with a control software aiming for load and coverage balancing. The control applies measurements of base station total transmission power of neighboring cells and(More)
The paper validates the feasibility of auto-tuning of serviceand bit rate-specific EbNo requirements. The planned EbNo values can be used e.g., to scale the powers when service is varying. The proposed methods, one for uplink and one for downlink, are tested using dynamic WCDMA system simulator with a deployment of macro cells on a city region whose(More)
We studied the responses of micropropagated, northern provenances of downy, mountain and silver birches to elevated ozone (O(3)) and changing climate using open-top chambers (OTCs). Contrary to our hypothesis, northern birches were sensitive to O(3), i.e. O(3) levels of 31-36 ppb reduced the leaf and root biomasses by -10%, whereas wood biomass was affected(More)
camera-design specifications determine the often unusual classroom behavior of these systems. System components were designed to meet SX-70 camera constraints: the system reliably determines ranges from about 0.4 m–11 m, operates on battery power (lowvoltage, high-peak current), is simple to use, and is rugged and inexpensively mass-manufactured. The(More)
Real communication channels with multipath propagation, interference and possible nonlinearities pose a difficult problem to the detecting receiver. This paper deals with neural approaches to solve those difficulties. Two types of neural networks, self-organizing map and radial basis functions have been studied. The results show that, while there are no(More)
The electricity planning department of eThekwini Municipality performs a power system load forecast based on individual substation forecasts. The individual substation forecasts have uncertainty. It is desired to understand the effect of these uncertainties on the accuracy of the total system forecast. A Monte Carlo simulation of the forecasted system(More)