Which of the following is a type of modulation commonly used in TBS communications?

The correct answer is that both Amplitude Modulation (AM) and Phase Shift Keying (PSK) are commonly used types of modulation in TBS communications.

Amplitude Modulation (AM) is a well-established method that varies the amplitude of the carrier signal to correspond with the information being sent. It is particularly effective for broadcasting over large distances and is commonly used in radio communications, making it relevant to TBS systems that may rely on traditional radio frequency transmissions.

Phase Shift Keying (PSK) is another modulation method that conveys data by varying the phase of the carrier wave. It is particularly efficient for digital communication, allowing for the encoding of multiple bits of information per cycle of the carrier signal. This method is widely utilized in modern digital communication systems, including TBS communications, as it can provide higher data rates and improved performance in the presence of noise.

Since both AM and PSK serve important roles in the modulation techniques used within TBS communications, selecting the combination of both as the answer reflects the understanding that both analog and digital modulation strategies are integral to effective communication in these systems.