An array antenna consists of two identical half-wave dipole antenna elements. The array operates in air...
A uniform plane wave traveling along the negative z-axis given by impinges upon an crossed-dipole antenna consisting of two identical dipoles, one directed along the x-axis and the other directed along the y-axis, both fed with the same amplitude. The y-directed dipole is fed with a 90◦ phase lead compared to the x-directed dipole. (a) Write an expression for the polarization unit vector of the incident wave. (b) Write an expression for the polarization unit vector of the receiving antenna...
An astronomical radio telescope consists of two antennas separated by a distance of 206 m. Both antennas are tuned to the frequency of 24 MHz. The signals from each antenna are fed into a common amplifier, but one signal first passes through a phase selector that delays its phase by a chosen amount so that the telescope can "look" in different directions. When the phase delay is zero, plane radio waves that are incident vertically on the antennas produce signals...