Correlation between antenna radiation pattern and field performance for global positioning systems in telematics as a function of antenna placement

The effect of antenna placement on the global positioning system (GPS) performance in telematics is investigated. Two sets of measurements were conducted. The first set consisted of measuring the vehicle-level antenna radiation pattern at three distinct antenna locations on a sedan vehicle. The second set consisted of a series of drive tests in three distinct driving environments. The field data were collected in parallel for each antenna location in all driving environments. GPS availability and accuracy results from the field testing are correlated to the vehicle-level antenna radiation pattern measurements. Results are presented to show the impact of the antenna placement on the GPS system performance and to demonstrate the good correlation between the vehicle-level radiation pattern measurements and the performance in the field.