i.Define the polarization of an antenna. Then state three main types of polarizations and discuss their differences in regard to the axial ratio. ii.State two different methods by which one patch antenna can generate a circular polarization.:= (b) A spiral antenna has an input impedance of 60 + j5 Q, a radiation loss of-0.7 dB, a directivity of 6.5 dBi and is fed by a 50 Q cable. Calculate: i.The antenna reflection co-efficient. i.The total output power if the input power is 1 Watt (answer in dBm). ii.The antenna realized gain. (c) For a linear array of N isotropic elements placed along a line with inter-element spacing of d. i.Write an expression for the array factor. ii.What are the conditions for which the array has maximum and nulls? (d) Describe the advantages of a waveguide over a transmission line. (e) State the type of antenna deployed for the following applications and briefly explain why. i.Cell phone handsets ii.Global Positioning System receiver iii.Very long-distance communications, e.g., for satellites

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