- Industry: Telecommunications
- Number of terms: 29235
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ATIS is the leading technical planning and standards development organization committed to the rapid development of global, market-driven standards for the information, entertainment and communications industry.
The rapid reduction of the ability of a system, subsystem, component, equipment, or software to perform its intended function. Note: Catastrophic degradation usually results in total failure to perform any function.
Industry:Telecommunications
The rapid changing, as opposed to long-term drifting, of the frequency of an electromagnetic wave. Note: Chirping is most often observed in pulsed operation of a source. 2. A pulse compression technique that uses (usually linear) frequency modulation during the pulse.
Industry:Telecommunications
The range that corresponds to the situation in which a radar transmitter is on and hence the receiver must be off, so that the radar transmitted signal does not saturate, i.e., does not blind, its own receiver. Note: Radar blind ranges occur because there is a time interval between transmitted pulses that corresponds to the time required for a pulse to propagate to the object, i.e., to the target, and its reflection to travel back. This causes an attempt to measure the range just as the radar transmitter is transmitting the next pulse. However, the receiver is off, therefore this particular range cannot be measured. The width of the range value that cannot be measured depends on the duration of the time that the radar receiver is off, which depends on the duration of the transmitted pulse. The return-time interval could be coincident with the very next radar-transmitted pulse, i.e., the first pulse following a transmitted pulse, or the second, or the third, and so on, giving rise to a succession of blind ranges. The blind ranges are given by rm = (mc) / (2fn,) where rm is the blind range for a given value of m, m is a positive integer that indicates which of the blind ranges is being determined, c is the velocity of electromagnetic wave propagation in vacuum (approximately 3 × 108 m/s,) f is the radar pulse repetition rate, and n is the refractive index of the transmission medium (nearly 1 for air. ) The radar blind range is independent of the radar radio frequency (rf) of the radar pulse.
Industry:Telecommunications
The range of frequencies within which a closed-loop system can acquire and track a signal. 2. The dynamic range within which a closed-loop system can acquire and track a signal.
Industry:Telecommunications
The range of frequencies over which a phase-locked loop can vary and still maintain frequency lock.
Industry:Telecommunications
The range of frequencies of electromagnetic radiation from zero to infinity. Note: The electromagnetic spectrum was, by custom and practice, formerly divided into 26 alphabetically designated bands. This usage still prevails to some degree. However, the ITU formally recognizes 12 bands, from 30 Hz to 3000 GHz. New bands, from 3 THz to 3000 THz, are under active consideration for recognition. Refer to the figure below.
Industry:Telecommunications
The radius of a hypothetical Earth for which the distance to the radio horizon, assuming rectilinear propagation, is the same as that for the actual Earth with an assumed uniform vertical gradient of atmospheric refractive index. Note: For the standard atmosphere, the effective Earth radius is 4/3 that of the actual Earth radius.
Industry:Telecommunications
The radius below which an optical fiber or fiber-optic cable should not be bent. Note 1: The minimum bend radius is of particular importance in the handling of fiber-optic cables. It will vary with different cable designs. The manufacturer should specify the minimum radius to which the cable may safely be bent during installation, and for the long term. The former is somewhat shorter than the latter. Note 2: The minimum bend radius is in general also a function of tensile stresses, e.g., during installation, while being bent around a sheave while the fiber or cable is under tension. Note 3: If no minimum bend radius is specified, one is usually safe in assuming a minimum long-term low-stress radius not less than 15 times the cable diameter.
Industry:Telecommunications
The Radiocommunications Sector of the ITU; responsible for studying technical issues related to radiocommunications, and having some regulatory powers. Note: A predecessor organization was the CCIR.
Industry:Telecommunications
The quotient obtained by dividing the signal-to-noise ratio (SNR) at the output of an FM receiver by the carrier-to-noise ratio (CNR) at the input of the receiver. Note: When the FM improvement factor is greater than unity, the improvement in the SNR is always obtained at the expense of an increased bandwidth in the receiver and the transmission path.
Industry:Telecommunications
