10.5. In Section 10.6 we showed how a DFT can be used to compute the radiation pattern of a linear phased array. Consider a linear of 64 elements at half wavelength spacing, where an FFT of size 512 is used to compute the pattern.

What are the FFT bins that correspond to steering angles ?

d = 3m E(ς) D(y)

E(ς) D(y) 2πj yλ

 --- sinς

exp  dy

–r ⁄ 2 r ⁄ 2

= ∫

λ r E(ς) D(Y) = d0

λ ⁄ 2 0° 45°

60°

d = λ

β

d = λ d = λ ⁄ 2

β = 30°, 45°