Thread: Antenna design
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Old 26-Mar-2017, 4:54 AM   #18
GroundUrMast
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On another note... I tossed a simulation of your earlier antenna (post #10 of this thread) together, using 4NEC2

Code:
CM 
CE
SY AGL=0
GW	100	33	33/2	0	0+AGL	-33/2	0	0+AGL	#16
GW	101	3	33/2	0	0+AGL	33/2	0	3+AGL	#16
GW	102	3	-33/2	0	0+AGL	-33/2	0	3+AGL	#16
GW	103	16	33/2	0	3+AGL	0.5	0	3+AGL	#16
GW	104	16	-33/2	0	3+AGL	-0.5	0	3+AGL	#16
GW	105	3	0.5	0	3+AGL	0.5	0	6+AGL	#16
GW	106	3	-0.5	0	3+AGL	-0.5	0	6+AGL	#16
GW	201	16	33/2	0	6+AGL	0.5	0	6+AGL	#16
GW	202	16	-33/2	0	6+AGL	-0.5	0	6+AGL	#16
GW	203	3	33/2	0	6+AGL	33/2	0	9+AGL	#16
GW	204	3	-33/2	0	6+AGL	-33/2	0	9+AGL	#16
GW	205	16	33/2	0	9+AGL	0.5	0	9+AGL	#16
GW	206	16	-33/2	0	9+AGL	-0.5	0	9+AGL	#16
GW	207	3	0.5	0	9+AGL	0.5	0	12+AGL	#16
GW	208	3	-0.5	0	9+AGL	-0.5	0	12+AGL	#16
GW	301	16	33/2	0	12+AGL	0.5	0	12+AGL	#16
GW	302	16	-33/2	0	12+AGL	-0.5	0	12+AGL	#16
GW	303	3	33/2	0	12+AGL	33/2	0	15+AGL	#16
GW	304	3	-33/2	0	12+AGL	-33/2	0	15+AGL	#16
GW	305	16	33/2	0	15+AGL	0.5	0	15+AGL	#16
GW	306	16	-33/2	0	15+AGL	-0.5	0	15+AGL	#16
GW	307	3	0.5	0	15+AGL	0.5	0	18+AGL	#16
GW	308	3	-0.5	0	15+AGL	-0.5	0	18+AGL	#16
GW	401	16	33/2	0	18+AGL	0.5	0	18+AGL	#16
GW	402	16	-33/2	0	18+AGL	-0.5	0	18+AGL	#16
GW	403	3	33/2	0	18+AGL	33/2	0	21+AGL	#16
GW	404	3	-33/2	0	18+AGL	-33/2	0	21+AGL	#16
GW	405	16	33/2	0	21+AGL	0.5	0	21+AGL	#16
GW	406	16	-33/2	0	21+AGL	-0.5	0	21+AGL	#16
GW	407	3	0.5	0	21+AGL	0.5	0	24+AGL	#16
GW	408	3	-0.5	0	21+AGL	-0.5	0	24+AGL	#16
GW	501	16	33/2	0	24+AGL	0.5	0	24+AGL	#16
GW	502	16	-33/2	0	24+AGL	-0.5	0	24+AGL	#16
GW	503	3	33/2	0	24+AGL	33/2	0	27+AGL	#16
GW	504	3	-33/2	0	24+AGL	-33/2	0	27+AGL	#16
GW	505	33	33/2	0	27+AGL	-33/2	0	27+AGL	#16
GS	0	0	0.0254
GE	0
GN	-1
EK
EX	0	100	17	0	1	0	0
FR	0	0	0	0	584	0
EN
The impedance is quite high making for a very high SWR.

Also, the pattern does not project front and rear as one would expect a panel antenna to do. Rather it has 4 lobes pointing downward... (see the attached 3DView which is from a perspective below the antenna.)
Attached Files
File Type: pdf MainCalc.pdf (21.8 KB, 481 views)
File Type: pdf 3DView.pdf (75.0 KB, 501 views)
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Last edited by GroundUrMast; 26-Mar-2017 at 4:59 AM.
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