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Principles of Modern Radar - Volume 2 1891121537

Principles of Modern Radar - Volume 2 1891121537

Principles of Modern Radar - Volume 2 1891121537

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13.9 Problems 627with the result in (a). Choose the reference angle α such that the x-component <strong>of</strong> thefield is real.4. An elliptically polarized wave is traveling along the z-direction with the phasor electricfield given by E = ( ˆx2 + ŷ1e jπ/4) e − jkz . Find the tilt angle, ellipticity angle, andsense <strong>of</strong> rotation <strong>of</strong> the polarization ellipse. Find a complex unit vector to represent itspolarization state in a linear (x − y) basis. It is required to represent this wave as a sum<strong>of</strong> two orthogonally polarized elliptical states, E = E 1 + E 2 = (ê 1 E 1 + ê 2 E 2 ) e − jkz .Assume that the field E 1 has tilt angle ψ = 30 ◦ and ellipticity angle τ =−22.5 ◦ .Using the linear-to-elliptical polarization basis transformation in (13.35), calculateE 1 ,E 2 , and determine the complex vectors for the orthogonal elliptical polarizationsstates ê 1 and ê 2 .5. Write the elliptically polarized wave <strong>of</strong> Problem 4 as the sum <strong>of</strong> two orthogonalcircularly polarized waves represented by the basis vector [ê r ê r⊥ ] (see (13.30)).6. An elliptically polarized wave is traveling along the z-direction with the phasorelectric field given by E = ( ˆx5 + ŷ8e jπ/8) e − jkz . Find the tilt angle, ellipticity angle,and sense <strong>of</strong> rotation <strong>of</strong> the polarization ellipse. Find the Stokes parameters and determinethe location <strong>of</strong> the polarization state on the Poincaré sphere. Also, determinethe antipodal polarization state and write its Stokes vector.7. If the Stokes parameters <strong>of</strong> a wave are given by g 0 = 3,g 1 =−2,g 2 = 1,g 3 = 2, findE x and E y , the tilt angle and the ellipticity angle. Show the location <strong>of</strong> its polarizationstate on the Poincaré sphere.8. Consider a wave with field components given by(E x = 2 cos ωt + π )8(E y = 3 cos ωt + 3π 2).Find the Stokes parameters and their Poincaré representation (13.21) in terms <strong>of</strong> tiltand ellipticity angles. Show the polarization state location on the Poincaré sphere.9. A partially polarized wave for which d = 0.5, AR = 2,ψ = 0 ◦ , and S = 1 (W/m 2 ),where S is the average power density <strong>of</strong> the wave, is incident on an antenna for whichAR = 4,ψ = 22.5 ◦ , and the effective aperture A e = 1m 2 . Find the received power.10. (a) A wave for which d = 0.4, AR = 3,ψ = 45 ◦ , and S = 1 (W/m 2 ) is separatelyreceived by six antennas, all <strong>of</strong> unit effective aperture, with polarization as follows:(i) linear horizontal, (ii) linear vertical, (iii) linear slant (45 ◦ ), (iv) linear slant(135 ◦ ), (v) left circular, and (vi) right circular. In each case, find the receivedpower.(b) Is there a wave to which all the six antennas listed in part (a) respond equally? Ifso, what are the wave parameters (tilt angle and axial ratio)?11. Show that a very thin square plate or disk <strong>of</strong> area A p has the scattering matrix in linearpolarization basis given byS = C[ 1 00 1], C = 2√ π A pλ

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