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a Matlab package for phased array beam shape inspection

a Matlab package for phased array beam shape inspection

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Contents<br />

1. Introduction 4<br />

2. Time steering and phase steering 5<br />

2.1. Time steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5<br />

2.2. Monochromatic signals—time-steering equals phase steering . . . . . . . . 7<br />

2.3. Phase steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7<br />

3. Antenna gain 8<br />

3.1. Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8<br />

3.2. Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11<br />

4. A <strong>phased</strong> <strong>array</strong> 15<br />

4.1. The <strong>array</strong> factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15<br />

4.2. Array factor as 2-D discrete Fourier trans<strong>for</strong>m of the excitation field . . . 17<br />

4.3. Grating zones and grating directions . . . . . . . . . . . . . . . . . . . . . 17<br />

4.4. Phase steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17<br />

4.5. The <strong>array</strong> factor with equal excitation amplitudes . . . . . . . . . . . . . 18<br />

4.6. Parseval’s theorem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19<br />

4.7. Antenna gain and the power integral . . . . . . . . . . . . . . . . . . . . . 19<br />

4.8. The power integral <strong>for</strong> an <strong>array</strong> with isotropic elements . . . . . . . . . . 20<br />

4.9. The power integral <strong>for</strong> an <strong>array</strong> with directional elements . . . . . . . . . 21<br />

4.10. Array gain <strong>for</strong> an <strong>array</strong> with directional elements . . . . . . . . . . . . . . 21<br />

4.11. Gain model <strong>for</strong> the <strong>array</strong> element . . . . . . . . . . . . . . . . . . . . . . . 22<br />

4.12. Computing the antenna directivity and <strong>beam</strong>width . . . . . . . . . . . . . 23<br />

4.13. Array gain and grating directions . . . . . . . . . . . . . . . . . . . . . . . 24<br />

4.14. 2-D <strong>beam</strong> cross section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25<br />

5. Phase and time accuracy 25<br />

5.1. Timing accuracy versus pointing accuracy . . . . . . . . . . . . . . . . . . 27<br />

6. Jitter calculations 28<br />

6.1. Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28<br />

6.2. Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30<br />

7. SNR estimate <strong>for</strong> the test <strong>array</strong> 30<br />

A. Figures to Chapters 2–7 34<br />

B. Pointing geometry 65<br />

C. <strong>Matlab</strong> functions 69<br />

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