In telecommunications, a standard test signal is a single-frequency signal with standardized level used for testing the peak power transmission capability and for measuring the total harmonic distortion of circuits or parts of an electric circuit.
Standardized test signal levels and frequencies are listed in MIL-STD-188-100 and in the Code of Federal Regulations Title 47, part 68.
Automatic Link Establishment, commonly known as ALE, is the worldwide de facto standard for digitally initiating and sustaining HF radio communications. ALE is a feature in an HF communications radio transceiver system that enables the radio station to make contact, or initiate a circuit, between itself and another HF radio station or network of stations. The purpose is to provide a reliable rapid method of calling and connecting during constantly changing HF ionospheric propagation, reception interference, and shared spectrum use of busy or congested HF channels.
In telecommunications, the term channel noise level has the following meanings:
In telecommunications, a combat-net radio (CNR) is a radio operating in a network that (a) provides a half-duplex circuit and (b) uses either a single radio frequency or a discrete set of radio frequencies when in a frequency hopping mode.
In telecommunications, the term conditioning equipment has the following meanings:
In signal processing, pre-emphasis is a technique to protect against anticipated noise and loss. The idea is to boost the frequency range that is most susceptible to noise and loss beforehand, so that after a noisy and lossy process more information can be recovered from that frequency range. Removal of the distortion caused by pre-emphasis is called de-emphasis, making the output accurately reproduce the original input.
In telecommunications, the term interposition trunk has the following meanings:
In telecommunications, net gain is the overall gain of a transmission circuit. Net gain is measured by applying a test signal at an appropriate power level at the input port of a circuit and measuring the power delivered at the output port. The net gain in dB is calculated by taking 10 times the common logarithm of the ratio of the output power to the input power.
In signal processing, phase distortion or phase-frequency distortion is distortion, that is, change in the shape of the waveform, that occurs when (a) a filter's phase response is not linear over the frequency range of interest, that is, the phase shift introduced by a circuit or device is not directly proportional to frequency, or (b) the zero-frequency intercept of the phase-frequency characteristic is not 0 or an integral multiple of 2π radians.
In telecommunications, attack-time delay is the time needed for a receiver or transmitter to respond to an incoming signal.
In telephony, single-frequency signaling is line signaling in which dial pulses or supervisory signals are conveyed by a single-frequency tone in each direction in the voice-band. SF and similar systems were used in 20th-century carrier systems.
A stopband is a band of frequencies, between specified limits, through which a circuit, such as a filter or telephone circuit, does not allow signals to pass, or the attenuation is above the required stopband attenuation level. Depending on application, the required attenuation within the stopband may typically be a value between 20 and 120 dB higher than the nominal passband attenuation, which often is 0 dB.
In telecommunications, a voice frequency primary patch bay (VF) is a patching facility that provides the first appearance of local-user VF circuits in the technical control facility (TCF).
MIL-STD-188 is a series of U.S. military standards relating to telecommunications.
In electronics, a limiter is a circuit that allows signals below a specified input power or level to pass unaffected while attenuating (lowering) the peaks of stronger signals that exceed this threshold. Limiting is a type of dynamic range compression. Clipping is an extreme version of limiting.
Secure voice is a term in cryptography for the encryption of voice communication over a range of communication types such as radio, telephone or IP.
A United States defense standard, often called a military standard, "MIL-STD", "MIL-SPEC", or (informally) "MilSpecs", is used to help achieve standardization objectives by the U.S. Department of Defense.
In electronics, crosstalk is a phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel. Crosstalk is usually caused by undesired capacitive, inductive, or conductive coupling from one circuit or channel to another.
MIL-STD-1760 Aircraft/Store Electrical Interconnection System defines a standardized electrical interface between a military aircraft and its carriage stores. Carriage stores range from weapons, such as GBU-31 JDAM, to pods, such as AN/AAQ-14 LANTIRN, to drop tanks. Prior to adoption and widespread use of MIL-STD-1760, new store types were added to aircraft using dissimilar, proprietary interfaces. This greatly complicated the aircraft equipment used to control and monitor the store while it was attached to the aircraft: the stores management system, or SMS.
In telecommunication, a measuring receiver or measurement receiver is a calibrated laboratory-grade radio receiver designed to measure the characteristics of radio signals. The parameters of such receivers can be adjusted over a much more comprehensive range of values than other radio receivers. Their circuitry is optimized for stability and enables calibration and reproducible results. Some measurement receivers also have exceptionally robust input circuits that can survive brief impulses of more than 1000 V, as they can occur during measurements of radio signals on power lines and other conductors.
A reference tone is a pure tone corresponding to a known frequency, and produced at a stable sound pressure level (volume), usually by specialized equipment.