Question

For N- element linear uniform array, the normalized array factor is represented as ______________

(a) \(\frac{sin(Nᴪ/2)}{Nᴪ/2}\)

(b) \(\frac{cos(Nᴪ/2)}{Nᴪ/2}\)

(c) \(N\frac{sin(ᴪ/2)}{ᴪ/2}\)

(d) \(N\frac{cos(Nᴪ/2)}{Nᴪ/2}\)

This question was posed to me in an online quiz.

I need to ask this question from Factors topic in section Antenna Array of Antennas

Answer 1

Correct choice is (a) \(\frac{sin(Nᴪ/2)}{Nᴪ/2}\)

The best explanation: The N-element linear uniform array, having a constant phase difference will have the array factor AF = \(∑_{n=1}^Ne^{j(n-1)ᴪ}\)  

Normalized array factor is given by \(\frac{sin(Nᴪ/2)}{Nᴪ/2}\)