38 



TRANSMISSION EXPERIMENTS AT ANTIGUA, WEST INDIES 



lull with the auteiuia several feet below the top to 

 see if trausmission over the hill was possible. There 

 was a noticeable decrease in signal strength, approxi- 

 mately 13 db, but some signal was still recorded. 

 Meteorological measurements were taken simul- 

 taneously with the inland radio measurements. Kite 



similar to those fouiul on the windward side of the 

 island existed. 



During the final phases of the project, an X-band 

 radar was installed at the base of the tower with an 

 antenna height of 6 ft. Measurements of echo strength 

 versus range were made on the PC boat to evaluate the 



40 60 60 100 120 140 



Figure 5. X-b;uid runs with 16- to 14-ft antenna combination. 



I6Q 



soirndings at several points at increasing distances 

 inland from the water's edge were made, and detailed 

 soundings on a 50- ft windmill tower about M; mile 

 inland were recorded over a 12-hr period. 



Additional meteorological measurements from the 

 ship on the leeward side of the island were made to 

 determine if duct conditions existed in this area. 

 Measurements taken from 2 miles out to approxi- 

 mately 20 miles off shore showed that duct conditions 



effect of the duct on X-band radar. Antenna heights 

 of the radar were varied from 6 ft to approximately 

 90 ft by placing the installation on the truck in much 

 the same manner as was done with the receiver in the 

 one-way experiment. This was then set np on sites 

 overlooking the coastline to sea. The heights at which 

 signal strength versus range measurements were made 

 were 6, 15, 50, and 00 ft. The variation in the range 

 of sea clutter for these heights was also observed. 



