Cellular radio systems use frequencies between 800 and 900 Megahertz (MHz), while PCS transmitters use frequencies in the range of 1850 – 1990 MHz. The combination of antennas and associated electronic equipment is referred to as a base station or cell site. The antennas mounted atop the Hi-Nella water tower are called sector antennas, which have the appearance of rectangular panels. Typically these types of antennas are arranged in groups of three, with one antenna in the group being used to transmit signals and the other two antennas receiving signals. At a cell site, the total RF power that could be emitted from each transmitting antenna depends on the number of radio channels (transmitters) that have been authorized and the power of each transmitter. Not all transmitters are expected to operate simultaneously, thus reducing typical overall emission levels.

The signal from a PCS base station antenna is essentially directed toward the horizon in a relatively narrow pattern in the vertical direction. The radiation pattern for a sector antenna is fan-shaped, like a wedge cut from a pie. As with all forms of electromagnetic energy, the power density from a PCS transmitter decreases rapidly as one moves further away from the antenna. As a result, normal ground-level exposure is much less than exposures that might be encountered if one were very close to the antenna and in its main transmitter beam. Historically, measurements made near typical cellular or PCS base station antennas have shown that ground-level power densities are well below regulatory limits and are typically on the order of 1 microwatt/centimeter (cm)² or less.  For comparison, in Subchapter 42, the plane wave equivalent power density limits for RF radiation between the frequencies of 1500 MHz and 100 GHz is 5,000 microwatts/cm² (or 5 milliwatts(mW)/cm²).

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