How does frequency division multiple access (FDMA) operate?

Frequency Division Multiple Access (FDMA) operates by allocating distinct frequency bands or channels to different users within the same communication medium. In this method, the overall frequency spectrum is divided into smaller, narrower frequency bands, which are then assigned to individual users or services. This allows multiple users to communicate simultaneously without interference, as each user transmits and receives their signals on their specific frequency channel.

The key aspect of FDMA is that all users can use the spectrum concurrently, but they are isolated from each other by these distinct frequency allocations. This method is particularly useful in environments where multiple communication services need to coexist without significant overlap or interference. Each user can continuously transmit on their assigned frequency, making it efficient for various applications, from cellular communications to radio broadcasting.

In contrast, the other options describe different methods of coordinating communications. Dividing time slots pertains to Time Division Multiple Access (TDMA), multiplexing signals refers to techniques like Frequency Division Multiplexing (FDM) or Time Division Multiplexing (TDM), and varying amplitude is related to Amplitude Modulation (AM) techniques. Understanding these distinctions is essential for identifying the unique operations of FDMA.