A Novel Sampling Method for the Spatial Frequencies of Sinusoid-Based Shadowing Models

Abstract

Careful modeling of the radio channel characteristics is an important issue for system level simulations. While a number of detailed path loss, shadowing and fast fading models can be found in literature, many of them entail large computational efforts and hence lead to long simulation times, or require huge amounts of memory. In this paper, we focus on shadowing models with two-dimensional correlation properties. We present handover performance evaluations as a use case from which requirements to the modeling of the shadow fading are derived. For different implementations of the shadow fading in system level simulations, we discuss their pros and cons and then focus on the sum of sinusoid model proposed by Cai and Giannakis [1]. Our main contribution lies in a new frequency sampling method to determine the coefficients of the sinusoidal waveforms. We show that this new method, denoted as Power Sampling Method (PSM), allows for a significant reduction of the number of sinusoids while the correlation properties of the shadow fading channel are preserved.

Vertical Antenna Tilt Optimization for LTE Base Stations

“…The measurement interval is 100 h divided by the number of terminals and based on a random-walk mobility model. Spatially correlated shadow fading [14] with a decorrelation length of 50 m and a standard deviation of 8 dB is applied. The outage is realized by decreasing the base station power to -200 dBm.…”

A fuzzy reinforcement learning approach for self-optimization of coverage in LTE networks

“…That is (12) where Λ represents the conjunction operator. The role of the selected parameter is to limit the update procedure to only the selected actions in fired states.…”

“…For the sake of computing time, all shadow fading values are precalculated, stored in large matrices, and loaded into the simulation environment. Interested readers can consult [12] for further information regarding shadow fading. Fast fading is not modeled in this study since the coverage and capacity are on a much longer timescale.…”

“…For these reasons, a statistical measure based on the distribution of LTE capacity values observed in the coverage area will be employed here, namely, the fifth percentile of this distribution. This measure of coverage is well known, widely accepted, and used in a similar way in [12].…”