Final answer:
Amplitude Modulation (AM) varies the carrier wave's amplitude while Frequency Modulation (FM) varies the wave's frequency; both methods are used to transmit voice and data signals via electromagnetic waves. Digital Encoding converts data into binary for clearer transmission and compression.
Step-by-step explanation:
The question pertains to methods of transmitting voice and data signals using electromagnetic waves through modifications of the wave's characteristics. Amplitude Modulation (AM) and Frequency Modulation (FM) are two types of modulation used for analog signal transmission, where AM involves varying the amplitude of the carrier wave and FM involves varying the frequency of the carrier wave. For digital data, such as cell phone conversations, Digital Encoding is used where the information is represented as a binary sequence of ones and zeros, which provides clearer data transmission and allows for compression.
In amplitude modulation, a carrier wave's amplitude is changed in proportion to the audio signal's amplitude while its frequency remains constant. This technique allows AM radio to transmit audio information over long distances within a frequency range of 540 to 2830 kHz. Frequency modulation, on the other hand, keeps the amplitude of the carrier wave constant while varying its frequency by the audio signal's amplitude, enabling FM radio to transmit signals in a higher frequency range of 87.5 to 108.0 MHz, leading to a higher quality of sound.