A concept used to determine the direction from which a signal is transmitted. Multiple antennas are used to receive a signal from a transmitter. Antennas are positioned with different views of the incoming signal, and the difference in the arrival time and phase of the signal at each antenna is used to calculate the signal's arrival angle.
A device that transmits or receives radio waves. To transmit, an antenna converts an electric current into radio waves, and it does the opposite to receive. Different antennas are used to send and receive at different frequency ranges.
Two or more antennas arranged to create a directional receiving pattern or arranged to allow measurement of phase difference between the antennas. An array can be used to create a line of bearing toward an RF transmission source.
The range of frequencies within the spectrum that can be used for a particular communication system to transmit information without significantly losing quality.
The specific frequency at which a radio signal or other form of electromagnetic radiation is transmitted or received. The center frequency is the midpoint or measure of the central frequency between the upper and lower cut-off frequencies (signal frequency range).
A unit of measurement used to express the ratio between two values, typically the ratio of two power or amplitude levels. The decibel scale is logarithmic, meaning that a change of one decibel corresponds to a multiplication of the quantity being measured by a constant factor.
A unit of measurement used to express the power of an electrical signal in decibels (dB), relative to 1 milliwatt (mW).
The process of extracting information from a modulated RF carrier signal. RF signals are often modulated to carry information, such as voice, video, or data’ therefore, demodulation is necessary because the information carried by the modulated RF carrier signal cannot be directly accessed or decoded. Demodulation recovers the original information signal by removing the carrier signal and extracting the modulating signal.
The difference between the weakest and strongest signals that a system can detect and monitor. The dynamic range for an RF monitoring system is the difference between the noise floor and the strongest signal.
The ratio of an amplifier device’s output power to the input power, expressed in dB.