IE MHz vertical profiles at distances of 0, 8 5 ° *£J°° in th0 usands of 

 center of a business area are shown in figure 7. Altitude, in tn 

 feet is Plotted on the vertical axis with the height gain, F plotted in 

 2/Wb along the horizontal axis. Note the increase in heigh, ga-n 

 distance of 50 miles from the business center. 



<kFT> 



20 



HEIGHT CfllH 



Figure 7. Daytime 45 MHz man-made radio noise model for 

 distances of 0, 8, 50 and 100 miles from the center of a 

 business area. Height gain (F^dB/kTb), is plotted as a 

 function of altitude in thousands of feet. 



4.2 HORIZONTAL PROFILE 



This program produces horizontal profiles of airborne ««-"** ™*£ 



on the vertical axis and distance from the area center in miles is plotted 

 .lone ^ the horizontal axis. Note how the noise peak above the city widens with 

 increasing altitude. 



12 



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