RF antennas are devices used to transmit and receive radio-frequency signals wirelessly in communication systems, radar systems, wireless networks, and RF identification systems. They convert electrical signals into electromagnetic waves for transmission and vice versa for reception. RF antennas come in various types, including omnidirectional antennas, directional antennas, patch antennas, yagi antennas, and helical antennas, each optimized for specific RF applications and performance requirements. RF antennas play a critical role in determining the coverage area, range, and signal strength of RF communication systems. They are essential components in RF transmitters, receivers, transceivers, and wireless devices, enabling wireless communication and data exchange over radio-frequency channels.