a shift in a biological rhythm along its time axis so whilst the period remains the same the time at which the rhythm occurs changes e.g. a rhythm normally occuring at 2pm experiences a 2 hour phase shift and so then starts at 4pm instead. The term phase shift is also used to mean the resetting of a rhythm; either as an advance shift (i.e.earlier ), or as a delay shift (i.e. later ) along the rhythms time axis.
the displacement in time of one waveform relative to another of the same frequency and harmonic content. Caused by switching on or off of strong loads, opening or closing of parallel lines, increasing or decreasing of system short-circuit power, and short-circuit onset and extinction.
Frequency interaction in the crossover region of passive crossovers which can cause some frequencies to be delayed with respect to other frequencies.
Situation in which the relative position in time between the clock and data signals of a transmission becomes unsynchronized. In systems using long cables at higher transmission speeds, slight variances in cable construction, temperature, and other factors can cause a phase shift, resulting in high error rates.
The change in phase of a periodic signal with respect to a reference.
a slight time difference between two similar waveforms, which puts them out-of-phase with respect to each other.
The angle in degrees between an energizing voltage waveform and an output signal waveform.
The time difference between two or more signals measured between reference points on each signal and usually expressed in angular displacement degrees.
A change in phase angle between the input and output of a device or system. This would normally be specified at several frequencies, or as a continuous curve as a function of frequency.
The phase relationship of two signals at a given time, or the phase change of a signal over an interval of time.
The changing of phase of a signal, as it passes though a filter. A delay in time of the signal, is referred to as phase lag. In normal networks, phase lag increases with frequency, producing a positive envelope delay (see envelope delay). - The figure of merit of a capacitor or inductor. The ratio of its reactance to its equivalent series resistance. Also, in bandpass filters, “loaded Q” is a term used to define the percentage of 3dB bandwidth. LOADED Q = Center Frequency (Fc)/ 3dB Bandwidth
A change in the phase of a rhythm. This change can be measured by observing a change in the timing of a phase reference point (e.g., activity onset or the nocturnal rise in the release of the hormone melatonin) from the timing expected based on previous, free-running cycles. Phase shifts may be either advances (i.e., the phase reference point occurs earlier than normal) or delays (i.e., the phase reference point occurs later than normal).
A phase shift implies a change from the time location associated with a biological rhythm peak or trough. For example, the body temperature of a healthy person is usually lowest (trough) around 9AM and highest (peak) about 7 PM. A person who works at night and therefore lives a schedule which is basically opposite from the general population, will have the trough body temperature reading in the evening and a peak in the morning - a phase shift of roughly 180 degrees.
The term phase shift comes from the physical phenomena where a small change in a physical parameter causes a large-scale change in structure. For example, as the temperature goes below the freezing temperature, physical substances undergo a global shift from a liquid to a solid. The point at which the transition occurs is called the critical point. In the context of computation, a phase shift refers to a sudden qualitative change in the behavior of a process over a small change in one of its governing parameters. In the context of information retrieval, the term phase shift has been used to refer to a radical change in the number of matching documents retrieved over a small change in the query.
The difference between corresponding points on input and output signal wave forms (not affected by magnitude) expressed as degrees lead or lag.
The changing of a signal as it passes through a filter. A delay in time of the signal referred to as phase lag and in normal network phase lag increases with frequency, producing a positive envelope delay. Please see envelope delay. : The Q or figure merit of a filter, is a measure of the sharpness of response or its frequency selectivity. Please see "Loaded Q".
A measure of the offset between two periodic signals of the same frequency. Measured in degrees or radians/milliradians.
In the phase relation between one wave and another, phase shift occurs when one wave has been advanced or retarded through its cycle relative to a similar waveform.
The relative change in timing (phase) of a signal, or group of signals, at the output in relation to its input as the signal passes through a circuit. Phase shift in an amplifier, compact disc player or cassette deck results in blurring of stereo spatial localisation and, in serious cases, can cause unstable amplifier performance and distortions.
The difference in timing between two otherwise similar signals.
Change in phase of a wave form between two points, expressed as degrees of lead or lag.
The phase angle between the output signal and the applied acceleration.
1. Change in phase of a signal as it passes through a filter, some other system component, or a transmission medium. 2. The method employed for electronic beam steering in phased-array radar. 3. For polarimetric radar, the differential phase shift between the copolarized and cross- polarized components, a measure of the propagation effect interpreted in terms of the degree of preferred orientation of the scatterers in the propagation medium.