Yes, transmission signals for audio, video, images, and text files can be established using both amplitude and frequency modulation, both in wired and wireless communication systems.
Amplitude modulation (AM) is a technique where the amplitude of a carrier signal is varied in accordance with the modulating signal (e.g., audio, video, or data). It is commonly used for transmitting audio signals over radio frequencies. The range of AM signals can vary depending on factors such as transmitter power, antenna characteristics, and environmental conditions. In general, the range of AM signals can be several miles to hundreds of miles for long-range broadcasting.
Frequency modulation (FM), on the other hand, is a technique where the frequency of the carrier signal is varied based on the modulating signal. FM is commonly used for high-fidelity audio broadcasting and is also used for video and data transmission in some cases. The range of FM signals can be shorter compared to AM signals, typically ranging from a few miles to tens of miles. However, FM signals can be received with good quality within the coverage area.
In wired communication systems, such as Ethernet for data transmission or HDMI for audio and video transmission, amplitude and frequency are not used directly as modulation techniques. Instead, digital encoding schemes such as pulse amplitude modulation (PAM) or pulse code modulation (PCM) are employed to represent the data as discrete levels or codes.
Wireless communication systems, including Wi-Fi for data, Bluetooth for short-range communication, or cellular networks for mobile communication, utilize various modulation techniques, including amplitude-shift keying (ASK), frequency-shift keying (FSK), or more advanced modulation schemes like quadrature amplitude modulation (QAM) or orthogonal frequency-division multiplexing (OFDM). The range of wireless signals depends on factors such as transmit power, frequency, antenna design, and the presence of obstacles or interference sources.
It's important to note that the range of transmission signals can vary significantly depending on the specific system, frequency band, regulatory limitations, and environmental conditions. The ranges provided above are rough estimates and should be considered as general guidelines rather than precise values.