Analogue Signals
- Analogue signals are continuous and vary smoothly over time.
- They represent real-world phenomena like sound, light, and temperature.
- Continuous Variation: Unlike digital signals, which are discrete, analogue signals change gradually.
- Think of an analogue signal as a smooth wave in the ocean, continuously rising and falling.
- In contrast, a digital signal is like a series of stepped terraces, with distinct levels and no gradual transitions.
Key Characteristics of Analogue Systems
Voltage (V)
Voltage
The electromotive force from a power source that pushes electrons through a circuit, often described as electric pressure. Measured in volts (V)
Current (I)
Current
The flow of electric charge through a circuit, caused by the movement of electrically charged particles, such as electrons. Measured in amperes (A)
Resistance (R)
Resistance
The opposition to the flow of electrons in an electrical circuit. It can be calculated using Ohm’s Law, which relates resistance (R), voltage (V), and current (I): R=V/I. Measured in ohms (Ω)
Frequency (f)
Frequency
The rate at which an electrical signal alternates between positive and negative per second, measured in hertz (Hz).
Power (P)
Power
The rate at which electrical energy is transferred or used in a circuit, measured in watts (W). It depends on both voltage and current.
- Analogue systems are often described using sine waves, which represent pure frequencies.
- These waves are characterized by their amplitude (height) and frequency (number of cycles per second).
SI Units and Multipliers
Understanding the International System of Units (SI) is crucial for working with analogue systems.
