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AWP_unit-1 Only 07 Regulation
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UNIT -1 Radiation Mechanism, Current Distribution 1. a) Define i. Radial power flow ii. Radiation resistance for a short dipole iii. Uniform current distribution. b) Derive an expression for the antenna terminal impedance as a function of frequency and hence define its bandwidth. Nov10 2. a) Define i) Radiation pattern, Beam width, Directivity. b) Determine the power density for a radiated power of 1200w at a distance of 50 Km from an isotropic antenna? c) Present the current distribution of a thin wire antenna. Nov11 Antenna Parameters - Radiation Patterns, Beam widths, Patterns in Principal Planes, Main Lobe and Side Lobes, Directivity, Gain, Resolution 3. a) Define and explain the following terms. i) Gain ii) Directivity iii) Radiation Resistance iv) Bandwidth b) A source has bidirectional power pattern with a radiation intensity of U = 4Sinθ. Find its directivity and HPBW sketching the pattern. Nov10 4. a) Define and explain Directivity and Power Gain of an Antenna. Prove that the directivity of a half wave dipole is 2.15dB. b) What are principle planes? How the Antenna Beam Width is defined in such planes? Nov10 5. (a) Define and account for the presence of i. Radial Power Flow ii. Radiation resistance for a short dipole iii. Uniform Current Distribution. Nov 10 6. (a) Explain the following : i. Normalized Field Pattern ii. Beam Solid Angle iii. Beam Efficiency iv. Directivity.
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Transcript of AWP_unit-1 Only 07 Regulation
UNIT -1Radiation Mechanism, Current Distribution
1. a) Definei. Radial power flowii. Radiation resistance for a short dipoleiii. Uniform current distribution. b) Derive an expression for the antenna terminal impedance as a function of frequency and hence define its bandwidth. Nov10
2. a) Define i) Radiation pattern, Beam width, Directivity.b) Determine the power density for a radiated power of 1200w at a distance of 50 Km from an isotropic antenna?c) Present the current distribution of a thin wire antenna. Nov11
Antenna Parameters - Radiation Patterns, Beam widths, Patterns in Principal Planes,Main Lobe and Side Lobes, Directivity, Gain, Resolution3. a) Define and explain the following terms.
i) Gain ii) Directivity iii) Radiation Resistance iv) Bandwidth b) A source has bidirectional power pattern with a radiation intensity of U = 4Sinθ. Find its directivity and HPBW sketching the pattern. Nov10
4. a) Define and explain Directivity and Power Gain of an Antenna. Prove that the directivity of a half wave dipole is 2.15dB. b) What are principle planes? How the Antenna Beam Width is defined in such planes? Nov10
5. (a) Define and account for the presence ofi. Radial Power Flowii. Radiation resistance for a short dipoleiii. Uniform Current Distribution. Nov 10
6. (a) Explain the following :i. Normalized Field Patternii. Beam Solid Angleiii. Beam Efficiencyiv. Directivity.
7. a) Define and explain directivity and power gain of antenna. Prove that the directivity of a half wave dipole is 2.15dB.b) If maximum current in the antenna is 20amps, find the field intensity at a distance of 2kms along the axis perpendicular and at an angle 300 form the antenna. Nov11
8. a) Define and explain: Directivity and power gain for an antenna. What is the relation between the two? Prove that the directivity of a λ /2 aerial is 0.39db more than that of short dipole.b) Define the terms Aperture efficiency and Effective height. Nov11
Antenna Apertures, Aperture Efficiency, Effective Height9. a) Define Reciprocity theorem and prove it in case of an Antenna system.
b) Shoe that for a Hertzian dipole, the aperture area is 0.12 λ 2 and for a half wave dipole, it is 0.13 λ 2 and for an isotropic radiator, it is 0.08 λ 2. Explain the relation used. Nov11
10. a) Derive the relationship between directivity and effective area, directivity and effective length. b) Define
i) Radiation Intensity, ii) Beam Area, iii) Effective Height and iv) Resolution Nov10
11. a) Define i) Radiation pattern, Beam width, Directivity.b) Determine the power density for a radiated power of 1200w at a distance of 50 Kmfrom an isotropic antenna?c) Present the current distribution of a thin wire antenna. May-11
12. a) Define and explain directivity and power gain of antenna. Prove that the directivityof a half wave dipole is 2.15dB.b) If maximum current in the antenna is 20amps, find the field intensity at a distanceof 2kms along the axis perpendicular and at an angle 300 form the antenna. May-11
13. a) Define and explain: Directivity and power gain for an antenna. What is the relation?between the two? Prove that the directivity of a _/2 aerial is 0.39db more than that ofshort dipole.b) Define the terms Aperture efficiency and Effective height. May-11
14. a) Define Reciprocity theorem and prove it in case of an Antenna system.b) Shoe that for a Hertzian dipole, the aperture area is 0.12 . and for a half wavedipole, it is 0.13 . and for an isotropic radiator, it is 0.08 . Explain the relationused. May-11
15. (a) Derive the relationship between directivity and effective area, directivity and effectivelength.(b) Define(i) Radiation Intensity(ii) Beam Area(iii) Effective Height(iv)Resolution May-12
16. Find the effective length of _/2 dipole and _/4 monopole. Hence calculate theirDirectivities using the appropriate radiating resistances. May-12
17. (a)Define reciprocity theorem and prove it in case of a antenna system.(b)Show that for a Hertzian dipole, the aperture area is 0.12 and for a half-wave, it is 0.13 . And for an isotropic, it is 0.08 . Explain the relation used. May-12
18. (a) Define and explain the following terms.i) Gain ii) Directivity iii) Radiation resistance iv) Bandwidth(b)A source has bidirectional power pattern with a radiation intensity of U=4sin_. Find the directivity and HPBW sketching the pattern. May-12
