Which of the following statements about parabolic reflector systems are correct? 1. A front-fed shallow parabolic reflector antenna requires a feed horn with narrow radiation pattern relative to that for a deep dish 2. The noise temperature of a Cassegrain system is the highest when it looks at the horizon 3. The noise temperature of a front-fed parabolic antenna is the lowest when it looks at the Zenith 4. The sidelobe level of a parabolic reflector is highest for uniform aperture illumination Select the correct answer using the codes given below:

Which of the following statements about parabolic reflector systems ar

1.	Which of the following statements about parabolic reflector systems are correct? 1. A front-fed shallow parabolic reflector antenna requires a feed horn with narrow radiation pattern relative to that for a deep dish 2. The noise temperature of a Cassegrain system is the highest when it looks at the horizon 3. The noise temperature of a front-fed parabolic antenna is the lowest when it looks at the Zenith 4. The sidelobe level of a parabolic reflector is highest for uniform aperture illumination Select the correct answer using the codes given below:
A.	1, 2 and 3
B.	1, 3 and 4
C.	1, 2 and 4
D.	2, 3 and 4
Answer» D. 2, 3 and 4

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