The assessment of the aggregate e.i.r.p. of user equipment operating in the LTE cell

Until the next WRC, Resolution 749 (Rev.WRC-12) will serve as a regulatory framework for coordination of the 790-862 MHz band between countries wishing to use it for mobile services (IMT/LTE systems) and those having deployed an aeronautical radio navigation system. It contains the criteria for identifying potentially affected administrations with respect to the aeronautical radionavigation service, where the mobile service is operated according to the frequency arrangement 791-821/832-862 MHz. In this, the trigger condition is applied according to which the coordination distances between a base station in the mobile service and a potentially affected ARNS station should be used subject to the aggregate e.i.r.p. value of all user equipment (UE) operating simultaneously with the notified base station (BS). The last value couldn´t be predicted or determined by means of measurements on the stage of putting base station into operation. In July 2011 Ukrainian State Centre of Radio Frequencies has carried out a series of field test trials based on Alcatel-Lucent LTE class 3 equipment. One of the purposes of the trials was to study the potential impact of cumulative interference from the LTE stations on the other systems operating in the band 790-862 MHz. Their results illustrated the difficulty of predicting the e.i.r.p. value within experimental network segment. In reality the problem is even more complicated, as only predicted values of deployment density of user terminals can be used. Taking into account the key features of the LTE Uplink radio interface we propose very simple analytical approach for the estimation of the aggregate e.i.r.p. value of all user equipment operating in the cell.