A Modified Formulation of Path Loss Models for Broadcasting Applications

Abstract

In this paper, we have used exclusively the FM band as this band is slowly gaining its popularity due to the liberalization policy of Govt. of India for its implementation. So, it is absolutely essential to find best fit propagation model. In the present work, we have used the field strength measurements of two FM broadcasting stations, each operating on different transmitted power and at different transmitting antenna heights. These field strength measurements (readings) on conversion into path loss and thereafter further be compared with the various available path loss models. An appropriate modification has been suggested and applied after calculating the mean square error (MSE) between the measured path loss and calculated path loss with the help of available models. For practical implementation, all the measurements have been taken in Punjab state of India (border district of Gurdaspur). It is further emphasized that all the measurements have been taken in an open area, so suggested model in this paper would be the best fit for open area conditions in the north bordering area of Punjab. All the measurements (readings) have been taken using the Anritsu site master by carrying it using car and with the available Anritsu dipole antenna. Using the corrected (modified) formula we have been able to reduce the Mean Square Error (MSE) value to one fourth value. For 100 W FM broadcasting station the value of MSE is coming exactly within the 6 dB limit, which is the necessary and appropriate condition for the good propagation model and for 10 KW FM stations is nearly coming closer to the 6 dB, which is the limit of a good propagation model.