System Level Modeling and Optimization of the LTE Downlink

3. Physical Layer Modeling and LTE System Level SimulationTable 3.3.: Simulation parameters employed for the validation of the L2S model in the singlecell,single-user scenario.Frequency(2.14 GHz( ) 4π d f 3Pathloss [dB]max 10 log 10 , 0)cBandwidth1.4 MHzTX power, antenna5 W, omnidirectionallyNoise spectral density-160 dBm/HzChannel model ITU-R Pedestrian-A [97], block fadingChannel knowledgePerfectFeedback delaynoneNumber of eNodeBs 1Number of UEs 1y pos [m]4003002001000−100−200−300−400ROI SNR [dB]−300 −100 100 300x pos [m]20151050−5distance [m]45040035030025020015010050SNR vs. distance to eNodeB0−10 0 10 20 30 40SNR [dB]Figure 3.15: Left: SNR map over the simulated ROI (color scale limited to a [-5,20] dB SNRrange). Right: Relation between the distance from the eNodeB site and thepost-FFT SNR. Simulation parameters listed in Table 3.3.level simulator [78], which implements the PHY layer abstraction models presentedin Chapter 3. As performance measure, throughput has been chosen, as it is ultimatelythe metric of interest.The following transmit modes defined in [39], as well as antenna configurations, havebeen evaluated, in all cases under a Ped-A channel at 5 km/h:ˆ Single transmit antenna (mode 1): 1 × 1 (SISO), 1 × 2 (SIMO).ˆ Transmit Diversity (mode 2): 2×2.ˆ Open Loop Spatial Multiplexing (mode 3): 2×2, 4×2, 4×4.ˆ Closed Loop Spatial Multiplexing (mode 4): 2×2, 4×2, 4×4.For all of the listed configurations, link level and system level results are shownin Figures 3.16 and 3.17. For the SNR range between -10 and 40 dB, each plot44