Exercise A lossless resonant half-wavelength dipole antenna, with input impedance of 73 ohms, is ...
A lossless, resonant, center-fed half-wavelength (1/2) linear dipole, radiating in free-space is attached to a lossless transmission line whose characteristic impedance is 75 2. This dipole antenna has a radius of 0.03 2. Calculate the reflection coefficient and discuss how to improve the impedance matching.
4c1) The closest integer number of turns so that the input impedance is nearly 100 ohms 4c2)the overall efficiency of the antenna (using the number of turns obtained in 4c1) (4c) A N-tum resonant circular lossless loop, antenna. with a uniform current distribution and with a circumference of V10, is fed by a lossless balanced twin-lead transmission line with a characteristic impedance of 100 ohms, Neglecting proximity effects, determine the (4e1) the closest integer number of turns so that the...
Question 1 The power radiated by a lossless antenna is 10 watts. The directional characteristics of the antenna are represented by the radiation intensity of U = 2cos3θ watts/unit solid angle. Find the (a) Maximum power density at a distance of 1000 m (assume far-field distance) (b) Maximum directivity (c) Maximum gain Question 2 In target-search ground-mapping radars it is desirable to have echo power received from a target, of constant cross section, to be independent ofits range. For one such application, the desirable radiation intensity...
Calculate the maximum power density 1 km away from a half-wave dipole antenna that is radiating 100 milliwatts. Repeat the calculation for a dipole antenna that is much shorter than a wavelength. (The gain of a half-wave dipole antenna is 2.15 dBi.)
A λ/2 dipole, with a total loss resistance of 1 ohm, is connected to a generator whose internal impedance is 25 + j25 ohms via a 50-ohm λ/2-long lossless transmission line. Assuming that the peak voltage of the generator is 2 V and the impedance of the dipole, excluding the loss resistance, is 73 + j42.5 ohms, find the power a) supplied by the source (real) b) radiated by the antenna c) dissipated by the antenna
Name: Problem 2. (Option # 1 ) Five half wavelength dipole antennas are used as sources to form a linear phased array antenna, as shown below. These elements are all excited by sinusoidal current source of equal amplitude and phase followed by phase shifters. (9 pts.) a) If d 2, write the expression for array factor of the linear array. (9 pts.) b) Find total field at observation point P: (r, 0, 6) at far-field (i.e., kr>1). (8 pts.) c)...