FDMA, or Frequency Division Multiple Access, is a channel access method used in communication systems. It allows multiple users to share the same communication medium by assigning each user a specific frequency band. This way, users can transmit and receive data simultaneously without interfering with each other. In FDMA, the available bandwidth is divided into distinct frequency channels, each allocated to a different user. This technique is commonly used in various applications, including cellular networks and satellite communications, ensuring efficient use of the available spectrum while maintaining clear communication.