Further Validation of an Electromagnetic Macro Model for Analysis of Propagation Path Loss in Cellular Networks Using Measured Driving-Test Data

Received signal level measurements are frequently used to check the performance and the quality of service (QOS) inside the coverage area in cellular networks. These expensive, time-consuming measurements are carried out using actual driving tests to assess the coverage area of a base station for a given cell, and to thus evaluate the quality of service. In a driving-test measurement system, a receiving antenna is placed on top of a vehicle. The vehicle is then driven along radial and circular lines around the base station, to measure the received power and thus assess the quality of service. These driving-test measurements are also used to tune the empirical models in the radio-planning tools that have to be employed for various types of environments. This model tuning is a lengthy procedure. In this paper, it is shown that an electromagnetic macro modeling of the environment can provide simulation results comparable to the data one would obtain in an actual driving-test measurement for a cellular environment. The input parameters for the electromagnetic macro model can be generated using only the physical parameters of the environment, such as the height of the transmitting and receiving antennas over the ground, their tilts towards the ground, and the electrical parameters of the ground. Such analysis can provide realistic plots for the received power as functions of the separation distance between the receiving and the transmitting base-station antennas. The novelty of the electromagnetic-analysis technique proposed in this paper lies in its ability to match the macro-model-based simulation results and the driving-test measurements without any statistical or empirical curve fitting or an ad hoc choice of a reference distance. In addition, a new concept, called the proper route, is introduced to enhance the analysis of the measured data. A Method-of-Moments-based integral-equation-solver code has been used to simulate the effects of the macro parameters of the e- vironment on the propagation-path loss of the signals emanating from a base-station antenna. The perfect match between the simulation results and the driving-test data was illustrated by monitoring the signal levels from some cellular base stations in western India and Sri Lanka, and then comparing the observed results with the simulated results. The goal here is to illustrate that these numerical simulation tools can accurately predict the propagation path loss in a cellular environment without tweaking some non-physical models based on statistical modeling or heuristic assumptions.