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Ground reflections may add in phase with the direct wave,and essentially double the electric <br /> field intensity. Because power density is proportional to the square of the electric field, the power <br /> density may quadruple, that is, increased by a factor of 4. <br /> Since ERP is routinely used, it is necessary to convert ERP into EIRP; this is readily done <br /> by multiplying the ERP by the factor of 1.64, which is the gain of a half-wave dipole relative to an <br /> isotropic radiator. Therefore, downrange power density estimates can be calculated by using the <br /> formula: <br /> S = 4 • [ERP • 1.641 • G E = ERP • 1.64 • G E = 0.522 • ERP • G E <br /> 4 7L R2 7L R2 R2 <br /> The theoretical power density calculations for the personal wireless services providers are <br /> listed in Tables U-III for each three degree increment of depression angle(90' being straight down <br /> at the base of the monopole, and 0° being straight out from the antenna). The values have been <br /> calculated for a height of six feet above ground level in accordance with regulatory rational. <br /> To calculate the% MPE, use is made of the formula: <br /> % MPE= S 100 <br /> MPE <br /> The theoretical percent Maximum Permissible Exposure calculations for the personal <br /> wireless services facility carriers are also listed in Tables H-III for the same angle and height <br /> conditions. <br /> The summation of all theoretical percent Maximum Permissible Exposure calculations for <br /> the proposed installation are depicted in Figure 1 plotted against linear distance from the base of the <br /> monopole. In addition,and depicted for reference only,values have been plotted for a height of 16 <br /> feet above ground level for comparison with a typical two-story structure. A logarithmic scale is <br /> used to plot the calculated theoretical %MPE values in order to compare,with the MPE of 100%, <br /> which is so much larger that it would be off the page in a linear plot. <br /> From a purely isotopic RF source, the% MPE curve would demonstrate a straight-line on <br /> the log-linear plot;as shown at distances beyond about 2000 feet. Within about 2000 feet,the curve <br /> is variable due to the application of the vertical radiation patterns. <br /> 427 Amherst Street, Unit#11 <br /> Nashua,NH 03063 <br /> Page 4- <br />