Trivia Questions On Antenna Theory And Wave Propagation! Quiz

A horizontal antenna is horizontally polarized because the orientation of the antenna elements is parallel to the ground, resulting in the electromagnetic waves being transmitted or received in a horizontal plane. This polarization is commonly used in applications such as television broadcasting and long-range communication, where the signals need to propagate over long distances with minimal interference.

Azimuth is the horizontal pointing angle of an antenna. It represents the direction in which the antenna is pointed horizontally, measured in degrees clockwise from true north. This angle is crucial in determining the direction in which the antenna is transmitting or receiving signals. The other options, such as angle of elevation, right angle, and beamwidth, do not specifically refer to the horizontal pointing angle of an antenna.

An antenna array is a collection of individual antennas that are arranged in a specific pattern. Each individual antenna in the array is typically a half-wave antenna. The purpose of the array is to enhance the performance of the antenna system, such as by increasing the gain or directing the radiation pattern in a specific direction. Therefore, an antenna array can be described as an antenna with a number of half-wave antennas on it.

A parabolic dish antenna is the correct answer because it has a very high gain and a very narrow beamwidth. The parabolic shape of the dish allows it to focus radio waves onto a single point, resulting in a highly concentrated signal and increased gain. The narrow beamwidth means that the antenna can transmit and receive signals in a very specific direction, making it ideal for long-range communication and satellite applications.

A notch antenna is an open-ended slot antenna that is designed to suppress or reject signals in a specific frequency range. It consists of a narrow slot cut into a conducting surface, which creates a resonant circuit that attenuates signals at the desired frequency. This antenna is commonly used in applications where interference needs to be minimized or eliminated, such as in wireless communication systems or radar systems.

The correct answer is collinear. In a collinear antenna array, all the elements are aligned in a straight line. This configuration allows for a more focused and directional radiation pattern, which is useful for long-distance communication. Yagi, broadside array, and log-periodic antennas have different configurations and radiation patterns, so they are not the correct answers in this case.

The Marconi antenna is the correct answer because it radiates an omnidirectional pattern in the horizontal plane with vertical polarization. This means that the antenna emits signals in all directions horizontally, making it suitable for applications where a signal needs to be broadcasted evenly in all directions. The other options, such as the Discone antenna, Horn antenna, and Helical antenna, may have different radiation patterns or polarization orientations, making them unsuitable for this specific requirement.

The direction of the electric field vector determines antenna polarization. Antenna polarization refers to the orientation of the electric field in the radiated wave. It can be either vertical or horizontal, depending on the direction of the electric field vector. The orientation of the electric field vector is crucial in determining the efficiency and effectiveness of the antenna in transmitting or receiving signals.

The gain in dB is calculated using the formula: Gain (dB) = 10 * log10 (Pout / Pin), where Pout is the output power and Pin is the input power. In this case, the input power without the reflector is 20 kW and with the reflector is 11 kW. Plugging these values into the formula, we get: Gain (dB) = 10 * log10 (20/11) = 2.6 dB.

The correct answer is omnidirectional/vertical polarized. A discone antenna is designed to have a radiation pattern that is omnidirectional, meaning it radiates and receives signals equally in all directions. Additionally, the discone antenna is typically vertically polarized, meaning the electric field of the radio waves is oriented vertically. This combination of omnidirectional and vertical polarization makes the discone antenna suitable for applications where a wide coverage area is desired, such as in communication systems or radar systems.

Top loading is used in an antenna in order to increase its effective height. Top loading refers to the addition of an element or structure at the top of the antenna to extend its height. By increasing the height, the effective height of the antenna is increased, which improves its performance in terms of signal reception and transmission. This is especially important for antennas operating at lower frequencies, where a taller antenna is needed to achieve better coverage and increased gain.

The estimated medium wind loading in the Philippines for antenna tower design is 200 kph. This means that the antenna tower should be designed to withstand wind speeds of up to 200 kilometers per hour. This is an important consideration in the design process to ensure the structural integrity and stability of the tower in high wind conditions.

Lightning rods must be mounted at a height of at least 30 cm above the highest point of a structure. This is because lightning rods are designed to attract lightning strikes and provide a path for the electrical discharge to safely reach the ground, thus protecting the structure from damage. By placing the lightning rod at a higher point, it increases the likelihood that it will be the target for lightning strikes, rather than the structure itself.

FM broadcasting does not use vertical polarization antenna. FM stands for Frequency Modulation, and it uses horizontal polarization for transmitting signals. Horizontal polarization is preferred in FM broadcasting because it helps minimize signal interference and provides better signal quality.

A properly terminated antenna is one that has a termination impedance that matches the characteristic impedance of the transmission line it is connected to. The Rhombic antenna is known for its ability to be properly terminated, meaning that it can be matched to the transmission line impedance without causing reflections or signal loss. The Marconi, Dipole, and Yagi-Uda antennas may also be properly terminated, but the Rhombic antenna is specifically mentioned as the correct answer.