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Television network is a system of transmitting and receiving television signals over a large area. Antenna is a device that converts electromagnetic waves into electric currents or vice versa. Antenna plays a crucial role in the performance and quality of television network. In this paper, we will analyze different types of antenna for television network, such as dipole antenna, yagi antenna, parabolic antenna and fractal antenna. We will compare their advantages and disadvantages, and suggest some criteria for choosing the best antenna for different scenarios. Dipole antenna is the simplest and most common type of antenna for television network. It consists of two metal rods or wires of equal length that are connected to a transmitter or receiver. Dipole antenna can receive signals from any direction in a horizontal plane, but has a low gain and a narrow bandwidth. Dipole antenna is suitable for local television stations or indoor applications. Yagi antenna is a directional antenna that consists of a dipole antenna and several parasitic elements, such as reflectors and directors. Yagi antenna can focus the signals in one direction and reject the signals from other directions, thus increasing the gain and reducing the interference. Yagi antenna has a moderate bandwidth and can be easily adjusted to different frequencies. Yagi antenna is suitable for long-distance television network or outdoor applications. Parabolic antenna is another directional antenna that consists of a parabolic reflector and a feed horn. Parabolic antenna can concentrate the signals into a narrow beam and achieve a high gain and a wide bandwidth. Parabolic antenna can also receive signals from satellites or other high-altitude sources. Parabolic antenna is suitable for satellite television network or high-definition television network. Fractal antenna is a novel type of antenna that uses fractal geometry to design its shape and structure. Fractal antenna can have multiple resonant frequencies and a large effective area, thus increasing the bandwidth and the efficiency. Fractal antenna can also have self-similarity and scalability, which means it can be miniaturized or enlarged without affecting its performance. Fractal antenna is suitable for digital television network or wireless communication network. In conclusion, different types of antenna have different characteristics and applications for television network. Depending on the factors such as distance, frequency, direction, interference, quality and cost, one can choose the best antenna for their specific needs |
