Tiruppadiripuliyur Ranganathan Santha Kumar

Empirical relation for designing the meander line antenna

In meander line antenna the size of the dipole at given frequency is reduced by a factor that is proportional to the number of turns. The adjacent horizontal segments of the meander line antenna have opposite phase. The transmission line current neither contributes much to the radiated power nor produce losses. At the location where the current reaches maximum value at that point large amount of power is wasted which is close to the antenna centre. Hence the radiation resistance is affected by the vertical segments. The meander line structure is design on glass epoxy (FR4) substrate with thickness 3.2cm dielectric constant 4.4. The impedance matched between the feed and meander line antenna is being achieved by adjusting the width and length of the open end of the microstrip. The optimized parameters are obtaining by design equation d=0.16lambdag, s=0.33lambdag, w=0.06lambdag, L=0.7lambdag where lambdag is the guide wavelength in the glass epoxy substrate at the centre frequency of 1060MHZ. Similarly using design equation the dimension has also been obtained for 1025MHZ. An empirical relation between frequency and each dimension of the meander line and frequency relations giving the design of the meander line are validate for two different frequencies which are 1030MHZ and 1090MHZ. For validation dimensions of meander line antenna are calculated using above equations. Then separately the dimensions of the meander line are obtained using the standard formula. The value so obtained by two methods one by empirical relation and other by design equation are compared. It is found that the dimension obtained by both methods matched. Thus one can use these empirical relations for designing the meander line antenna.