ARRL Technician Practice Exam

What is a commonly used method of sending signals to and from a digital satellite?

1. AM Modulation

2. FM Packet

3. Single Sideband

4. Analog Telemetry

The correct answer is: FM Packet

The method of sending signals to and from a digital satellite that is commonly used is FM Packet. This technique allows for efficient transmission of digital data, which is essential for communication with satellites that often handle various types of packet data. FM (Frequency Modulation) is well-suited for this purpose because it provides reliable signal integrity even under various atmospheric conditions. The use of packet data is particularly advantageous in satellite communications due to its ability to efficiently encapsulate and transmit information, making it ideal for digital applications where bandwidth and error correction are important. Furthermore, FM Packet allows multiple users to share the same frequency channel, which is crucial in satellite operations where bandwidth may be limited. While other methods such as AM modulation and Single Sideband can be used for audio and voice communications, they are not as efficient for digital data transmission. Analog telemetry, although useful for monitoring and control purposes, does not provide the digital data transmission capabilities required for modern satellite communication. Thus, FM Packet stands out as the preferred method in this context.