b in addition to the possible voice communication between the td caller and the emergency response officer eliminating the need for the wlan transceivers on both mds 30 a 30 b and grd 100 a 100 b further the power control instructions transmitted by the on mds bs transmitter within mds 30 a to the grd 100 a 100 b can take the advantage of being able to coordinate with the mds 30 a measurement activity to optimize the signal to interference ratio for better location measurement accuracy of grd 100 a 100 b and increase the battery life of grd 100 a 100 b as well the frequency and other signal properties of the on mds bs transmitter should be chosen appropriately to minimize the impact to the wireless system operation of bs 20 a 20 b and their serving users fig7 illustrates the location determination system and the method associated with thereof in a three dimensional operation mode using a cellular phone as an example of td referring to fig7 in a preferred embodiment when at least one of mds 30 is sufficiently close to td 10 or after at least one of the mds 30 is parked on site the location measurement is conducted in three dimensions so that the height of td 10 and height of grd 100 would not be a degradation factor in determining location in horizontal plane and further said height of td 10 and height of grd 100 are also measured and reported on screen of grd 100 and on screen of mds 30 to provide additional location information the format of the display for height is preferably a.