Electronics and Communication Engineering - Microwave Communication - Discussion
Discussion Forum : Microwave Communication - Section 1 (Q.No. 22)
22.
The width of a radio beam from a 1 m diameter parabolic antenna at 10 GHz is about
Answer: Option
Explanation:
.
Discussion:
12 comments Page 1 of 2.
Rose said:
10 years ago
Kc/wavelength.
Where k is a factor which varies slightly depending on the shape of the reflector and the feed illumination pattern. For an ideal uniformly illuminated parabolic reflector and θ in degrees, k would be 57.3 (the number of degrees in a radian). For a "typical" parabolic antenna k is approximately 70.
How 140?
Where k is a factor which varies slightly depending on the shape of the reflector and the feed illumination pattern. For an ideal uniformly illuminated parabolic reflector and θ in degrees, k would be 57.3 (the number of degrees in a radian). For a "typical" parabolic antenna k is approximately 70.
How 140?
Dhruv said:
9 years ago
@All.
Beam width b/w half power points in a parabolic reflector = 70 * (lambda/diameter).
Therefore, beam width b/w first nulls = 2 * half power bw.
Then, we get 140.
Beam width b/w half power points in a parabolic reflector = 70 * (lambda/diameter).
Therefore, beam width b/w first nulls = 2 * half power bw.
Then, we get 140.
Tonitrum said:
3 years ago
λ = speed of light/frequency.
Beam width = 70λ/diameter.
Beam width = 140 λ/diameter.
Beam width = 70λ/diameter.
Beam width = 140 λ/diameter.
Sankar said:
8 years ago
I think 140 (λ) /diameter then we get above equation.
ZeCru said:
7 years ago
We use 70 for the Half Power Beam Width only.
Ayush Kumar said:
8 years ago
Yes beam width = 140(lambda)/diameter.
Sreeram said:
8 years ago
(140 (wavelength))/diameter.
Lavanya said:
1 decade ago
140 is for antenna factor.
Goldy said:
1 decade ago
Please explain in detail.
Aravind said:
1 decade ago
140c/wavelength.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers