Narrowband: In telecommunications, narrowband refers to a range of frequencies or a type of service with a dedicated, fixed bandwidth, typically measured in hertz, allowing for the transmission of data over a limited range of frequencies.
Noise Figure: a measure used to describe how sensitive a receiver is to electrical noise or unwanted signals from its circuitry. Effective sensitivity is generally computed as a ratio of the receiver’s signal-to-noise ratio to the noise figure.
Ohm: The standard unit of measurement for electrical resistance. One ohm is equivalent to one complete circuit resistance per volt of direct current (DC).
Ohms Law: The formula used to calculate the relationship between voltage, current, and resistance in an electrical circuit. The law states that the current (I) in an electrical circuit is equal to the voltage (V) divided by the resistance (R).
Ohmic Loss: A type of resistance loss in an electrical conductor. Ohmic losses are caused by electrical energy losses due to resistance, resulting in heat generation. Ohmic losses can be determined by measuring the voltage drop across the conductor.
Permeability: The property of a medium by which it can be penetrated or pulled in. For example, air and other gases are relatively permeable, allowing electrical and magnetic field to pass through them.
Phase: In alternating current (AC) circuits, the phase is the relative position of an electrical waveform to another waveform, in terms of its time. In a three-phase system, there are three waveforms, with each waveform being 120 degrees out of phase with the others.
Power Factor: A measure of the efficiency of an electrical circuit. It is the ratio of the real power divided by the apparent power, or the ratio of the useful output of a circuit to the total input.
Radius of Curvature: The radius of the curvature of a given curve or circle. In electrical systems, this term generally refers to the radius of a conductor or waveguide. The smaller the radius of curvature, the higher the capacitance and resistance.
Rectification: A process in which alternating current (AC) is converted to direct current (DC). Rectification can be achieved through the use of diodes, silicon controlled rectifiers (SCRs), or other electronic devices.
Relay: An electric switch that is actuated by an electric current or electromagnet to open or close the circuit. A relay can be used to control a large electrical load with a relatively small current.
Ripple: A term that describes the alternating waveforms on the waveform of a direct current (DC) after being rectified. Ripple is usually caused by the imperfections of the rectifier circuits.
