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According to the IEEE standard, an antenna is defined as "a means for radiating or receiving radio waves." It is essentially a physical arrangement of metallic conductors connected electrically to a transmitter or receiver, enabling the conversion between electromagnetic fields and alternating currents. At the transmitting end, alternating currents are driven through the conductors to generate oscillating magnetic fields, which propagate as electromagnetic waves. At the receiving end, these fields induce voltages that can be processed by the receiver. Antennas that transmit radio frequency signals are known as transmitting antennas, while those that capture such signals are called receiving antennas. They are indispensable components in various communication systems, including radio, wireless local area networks, mobile communication, and satellite systems. The rapid advancements in wireless technologies-such as WLAN, GPS, mobile phones, and Bluetooth-have led to a growing demand for compact and efficient antennas and filters. Integrating both elements into a single, miniaturized module enhances overall system performance by improving filtering and radiation characteristics. To meet modern communication requirements, antennas must exhibit sharp frequency selectivity, good harmonic suppression, and adjustable bandwidth. Antennas are broadly classified based on their directional characteristics into omnidirectional, directional, and arbitrary types. Omnidirectional antennas radiate and receive signals uniformly in the horizontal plane, whereas directional or high-gain antennas focus energy in specific directions to achieve greater range and efficiency. Parasitic elements and parabolic reflectors are often incorporated to shape the desired radiation pattern. Ultimately, antenna design depends on the intended application-whether for smartphones, cellular networks, GPS systems, or Wi-Fi communication-each requiring tailored structural and electrical characteristics to optimize performance.