System Level Modeling and Optimization of the LTE Downlink

3. Physical Layer Modeling and LTE System Level SimulationFor an example case considering a carrier frequency of 2 000 MHz and a base stationantenna height of 15 m above average rooftop level, the propagation model formulais simplified to the well known formula [69]L = 128.1 + 37.6 · log 10 (R) , (3.15)which is shown in Figure 3.6 (left).Combining the pathloss, antenna gain, and Minimum Coupling Loss (MCL) 5 , aposition-dependant macro-scale fading map depicting the losses from a given transmittersuch as that in Figure 3.7 (left) can be obtained. The cell partitioning can bevisualized by plotting the wideband SINR of the strongest signal on each point, denotedas Γ and not to be confused with the post-equalization SINR. The widebandSINR, depicted in Figure 3.6 (right), is calculated asΓ = G antenna L macro,0 P TX0. (3.16)N∑intσn 2 + L macro,l P TXmm=1The wideband SINR, also when applicable including shadow fading, can be employedas a measure of how close a UE is to the transmit antenna relative to the interferers,and is employed as such over the course of this thesis, especially in Chapter 5.y pos [m]pathloss [dB]10008006004002000−200−400−600−800−1000−1000 −500 0 500 1000x pos [m]18016014012010080cell SINR [dB]−1000 −500 0 500 1000x pos [m]20151050−5Figure 3.7: Left: pathloss and antenna gain map in dB. Pathloss and antenna gain as inEquation (3.15) and Figure 3.6. Antenna gain of 15 dBi. Right: resulting cellwideband SINR in dB.5 The MCL describes the minimum loss in signal between eNodeB and UE or UE and UE in theworst case and is defined as the minimum distance loss including antenna gains measured betweenantenna connectors. [69] defines it as 70 dB for urban cell deployments and 80 dB for rural celldeployments.35