Effect of Surface Error Distribution and Aberration on Electromagnetic Performance of a Reflector Antenna

Table 2

The result of effect of errors distributed in the normalized Zernike polynomials on EMP.

Term	Loss (dB)		Offset (″)		ΔSLD (dB)				Characteristic
	0 cut	90 cut	0 cut	90 cut	0 cut-L	0 cut-R	90 cut-L	90 cut-R
	0.01	0.01	0	0	0.4	0.4	0.4	0.4	Piston
	-0.28	0	0	-94.6	0.6	0.6	-2.6	3.4	Tilt
	0	-0.28	-94.6	0	-2.6	3.3	0.6	0.6	Tilt
	-0.2	-0.2	0	0	-2	-2	-2.7	-2.7	Astigmatism
	-0.44	-0.44	0	0	6.8	6.8	6.8	6.8	Defocus
	-0.19	-0.19	0	0	6.1	6.1	3.8	3.8	Astigmatism
	-0.17	-0.17	0	0	1	1	-7	8.3
	-0.35	-0.31	0	40.8	2.7	2.7	10.8	0.8	Coma
	-0.29	-0.33	40.8	0	10.7	1.35	2.5	2.5	Coma
	-0.17	-0.17	0	0	8	-2.6	0.6	0.6
	-0.16	-0.16	0	0	-0.3	-0.3	-0.1	-0.1
	-0.29	-0.29	0	0	-2.35	-2.35	-2.5	-2.5	2nd-astigm
	-0.37	-0.37	0	0	8.05	8.05	8.05	8.05	Spherical
	-0.28	-0.28	0	0	8.3	8.3	9.3	9.3	2nd-astigm
	-0.16	-0.16	0	0	5	5	4.6	4.6
	-0.14	-0.14	0	0	0.55	0.55	2.9	6.4
	-0.26	-0.26	0	0	0.3	0.3	8.8	6.7
	-0.34	-0.34	0	0	3.0	3.0	8.8	11.6	2nd-coma
	-0.33	-0.33	0	0	8.6	11.5	2.8	2.8	2nd-coma
	-0.26	-0.26	0	0	7.1	9	-0.8	-0.8
	-0.14	-0.14	0	0	-18.8	6.2	0.8	0.8

-L means the sidelobe level degradation on the left side; -R means the sidelobe level degradation on the right side.