A continuous wave (CW) and a modulated wave are two different types of signals in the context of communication systems. Here's an explanation of each:
Continuous Wave (CW): A continuous wave is a steady and uninterrupted signal that maintains a constant frequency and amplitude over time. It does not contain any modulation, which means it does not carry any information. CW signals are typically used for purposes like carrier waves in radio transmission or as reference signals in various applications. They have a fixed frequency and a single amplitude value throughout their duration.
Modulated Wave: A modulated wave, on the other hand, is a signal that carries information by modifying one or more of its characteristics, such as amplitude, frequency, or phase. Modulation is the process of impressing data or information onto a carrier wave, allowing the transmission of information over long distances. The carrier wave itself is typically a continuous wave (often a sine wave) that serves as a stable platform for the modulation process.
Modulation techniques include Amplitude Modulation (AM), Frequency Modulation (FM), and Phase Modulation (PM), among others. These techniques vary the amplitude, frequency, or phase of the carrier wave in accordance with the information being transmitted. By modulating the carrier wave, the original information is embedded into the waveform, enabling it to be transmitted efficiently and received correctly at the destination.
In summary, a continuous wave is a constant, unmodulated signal that does not carry any information, while a modulated wave is a signal that has been modified to encode and transmit information by varying one or more of its characteristics.