What does AM mean in UNCLASSIFIED

In AM, the modulating signal, which carries the information, varies the amplitude of the carrier wave. The carrier wave is a high-frequency signal that has a constant amplitude and frequency. When the amplitude of the carrier wave changes in response to the modulating signal, the resulting AM wave contains the information encoded in the modulating signal.

AM has several advantages, including:

• Simplicity: AM is a relatively simple modulation technique to implement.
• Compatibility: AM signals can be received by a wide range of receivers, making it compatible with many existing communication systems.
• Effective for voice transmission: AM is well-suited for transmitting voice signals, as it can effectively capture the amplitude variations of speech.

AM also has some disadvantages, such as:

• Susceptibility to noise: AM signals are susceptible to noise, which can interfere with the information being transmitted.
• Limited bandwidth efficiency: AM requires a wider bandwidth than other modulation techniques, which can limit its efficiency in certain applications.
• Carrier power waste: AM transmits both the carrier wave and the modulated signal, which results in a waste of power in the carrier.

AM is commonly used in applications such as:

• Broadcasting: AM is widely used for broadcasting radio signals, as it can be received by a wide range of receivers.
• Aeronautical communications: AM is used for voice communications in aviation, as it is reliable and effective for transmitting voice signals.
• Satellite communications: AM is sometimes used in satellite communications, where it can provide a simple and cost-effective means of transmitting data.