Study and Design of Second-Order Differential Arrays - Study and Design of Differential Microphone Arrays - page 61

90 ◦ 90 ◦

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120 ◦ 60 ◦ 120 ◦ 60 ◦

150 ◦ 30 ◦ 150 ◦ 30 ◦

180 ◦ 0 ◦ 180 ◦ 0 ◦

210 ◦ 330 ◦ 210 ◦ 330 ◦

240 ◦ 300 ◦ 240 ◦ 300 ◦

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(a) (b)

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150 ◦ 30 ◦

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180 ◦ 0 ◦

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210 ◦

330 ◦

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(c) (d)

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0 dB
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150 ◦ 30 ◦ 150 ◦ 30 ◦

180 ◦ 0 ◦ 180 ◦ 0 ◦

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(e) (f)

FIG. 4.2 Patterns of the second-order dipole for several frequencies and two values of Δ :
(a) F =0 . 5 kHz, Δ = 1 cm, (b) F =0 . 5 kHz, Δ = 2 cm, (c) F = 1 kHz, Δ = 1 cm, (d)
F = 1 kHz, Δ = 2 cm, (e) F = 3 kHz, Δ = 1 cm, and (f) F = 3 kHz, Δ = 2 cm.