169 



8a 



63 



L 

 T 

 1 

 T 

 U 

 D 43 



0-59 MILES 



<kFT> 



29 



13 



£4 



HEIGHT GAIN 



Fa (dB/kTb> 



Figure 6. Comparison of daytime 45 MHz man-made radio noise 

 model (solid line) and scaled Seattle data (crosses) directly 

 above and 50 miles from a business area. Height gain. 

 F (dB/kTb), is plotted as a function of altitude IP. thousands 

 of feet. 



The airborne man-made radio noise model has been ^'^.^Z^r 

 computer at NOSC. A series of program, generate graph* o J^J^^ 

 in three different formats. In the first format ^^^nce f^Ahe 

 produces height gain curves for any f "f^J^^Hne seC0 nd format, the 

 source that are selected in the range of the model. .In the se d 



horizontal profile program produces radio noUe^r ™™ S > fche last 



frequent and altitude, as a function of horizontal ^ -e. 

 fomat, the contour program produces contours of ca -~£"™ n ™ ed £aX BS . 

 for a selected frequency and altitude for the «**££ ^ Onit. 

 Each of the three types of model formats will be discussed 

 sections. 



4.1 VERTICAL PROFILE (HEIGHT GAIN) 



Thi, p» g r«. prod— hei,ht ,1. ««- »« «e ^^'"f^ 



sans: r^str »: »5r£«ii srs 



Equation (17) is used for distances of 7 J^^^^^^^eTcalculated and 

 used for distances greater than 7 .dies. J°f ff^f r ^ous section. If the 



ii 





i.-ji».^i-. 



/ 



