Short-term variations of the significant instants of a digital signal from their ideal positions in time. Regardless of the stability of clocks at both ends of a digital transmission system, certain amounts of instability occur in the received signal because of external electrical disturbances and changing physical parameters of the transmission link.

picture unsteadiness caused by timebase errors

Type of analog communication line distortion caused by abrupt, spurios signal variation from a reference timing position, and capable of causing data transmission errors, particularly at high speeds. (The variation can be amplitude, time, frequency, or phase.)

Variation in the time position of a read data event from the expected position.

Short-term variation of pulses from their ideal position in time.

Jitter is the variance of latency (i.e. delay) in a connection.

short waveform variations caused by vibration, voltage fluctuations, control system instability, etc.

Small rapid variations in a variable (such as a waveform) due to deliberate or accidental electrical or mechanical disturbances or to changes in the supply of voltages, in the characteristics of components. Jitter effects arising from the oscillating mirrors and other movable parts aboard the Landsat spacecraft are often a cause of certain anomalies in the image data received and must be compensated for by the ground processing software. Menu

As data load increases and decreases, routers on the Internet can create slightly different times that individual packets take to travel from one point to another point. This variation in time is known as jitter.

The variance in latency. Or variability in the delay of a stream of incoming packets making up a flow such as a voice communication.

A signal timing error that results in distortion of the received signal. In Internet terms, jitter is the measure of latency of individual packets in a message or stream. :: X Y Z : Home : Guide TOC

Fluctuations in a signal resulting in a signal that is not stable.

Analog communication line distortion caused by variations of a signal from its reference timing position.

The effect on arriving packets that retards or advances the packet timing relative to the average arrival time.

The difference between the time when a packet is expected to arrive and the time when a packet actually arrives. Also see latency and throughput.

(1) A distortion caused by the variation of a signal from its references which can cause data transmission errors, particularly at high speeds. (2) Variations in amplitude, time, frequency or phase.

Unwanted variations in the frequency or phase of a digital or analog signal.

The slight movement of a transmission signal in time or phase that can introduce errors and loss of synchronization. More jitter will be encountered with longer cables, cables with higher attenuation, and signals at higher data rates. Also, called phase jitter, timing distortion, or intersymbol interference.

On television and computer monitors, small vibrations or fluctuations in a displayed image caused by irregularities in the display signal. Jitter is often visible in horizontal lines that are the same thickness as scan lines. In facsimile transmission, a “rough” appearance produced by dots that are incorrectly recorded during the scanning process and thus wrongly positioned on the output.

small rapid variations in a waveform resulting from fluctuations in the voltage supply or mechanical vibrations or other sources

As data is sent across a network, it is broken down into pieces called packets, then reassembled when it reaches its destination. Jitter refers to the variation in delivery delay for packets crossing a network. This is an important measurement for VoIP networks because voice quality will suffer if the packets that make up a voice transmission do not arrive in an orderly, predictable fashion. A properly tuned network is necessary to prevent jitter and allow clear VoIP calls. Back

Jitter is a measure of the variability over time of the latency across a network. A very low amount of jitter is important for real-time applications using voice and video.

An unintended variation of a picture's vertical position. Jitter often takes the form of small, random vertical movements of the film in the gate.

Signal distortion on an analog communication line.

Variation in time of the sampling edge of the clock signal. Clock jitter can become a limiting factor in achievable SNR at Intermediate Frequencies.

When digital audio signals are transferred, the Word Clock of the devices must match. When samples are not output at their correct time relative to other samples, a type of noise called jitter will occur. A device with a more stable Word Clock will mean less jitter and better audio quality.

Jumping or instability in the television picture, often caused by synchronization or tracking errors.

The variance in latency between a source and target.

The variation in the arrival times of voice packets.

A measure of the short term frequency stability of the oscillator. It applies only to rectangular wave forms. It is measured as the uncertainty in the location of one edge of the signal with respect to other edges. It is usually specified in units of time (nano-seconds or pico-seconds), but may also be specified in degrees. This measurement has particular application to the digital communications industry.

Phase variation is usually measured statistically as a RMS deviation from a center value in degrees or radians. Usually caused in the input signal by noise but can be caused by encoders, modulators and channel distortion. Jitter is reduced by a bit sync depending on its loop bandwidth.

A tendency towards lack of synchronisation caused by electrical changes. The difference between when a digital edge (clock) transition is supposed to occur and when it actually does occur, causing errors & hence distortion in DACs & ADCs (linearity).

This referes to delay in transmission of data that needs to be contiguous, like voice or full motion video. The information must be received in the same speed that it was recorded, not sent. It can be downloaded in stages but must be "reassembled" and finally viewed or heard at the speed that the spoken voice or visual must be experienced. It is a key variable in Quality of Service (QoS).

The deviation of a clock's output from its ideal position.

Change in the phase angle between Channel A and B within one revolution(360°).

Difference in arrival time of packets sent over a network at the receiving end compared to the difference in packet spacing at the sending end.

Degradation of the signal as it traverses the cable or the Network Interface Cards (NICs). Common in token ring environments and causes errors in accuracy of signal.

Difference in arrival time of packets sent at the same time but traveling different routes.

Deviation from the original being copied.

The timing error or inconsistency between audio samples, when digital audio is being recorded or played back through a converter.

n. A variation in the transmission delay of digital signals.

When an electronic device (e.g. a television camera) generates a signal, the synchronisation signals are not absolutely stable, i.e. there is a small amount of timing jitter around a mean. An electro-mechanical device (e.g. a video player) generates a significantly higher amount of jitter due to the mechanical tape transport mechanism.

Temporal variation in a signal from an ideal reference clock. There are many kinds of jitter, including sample jitter, channel jitter, and interface jitter.

Jitter occurs when digital audio loses sync. Along with the actual audio data, digital audio signals (either S/PDIF or AES/EBU) carry a synchronization bit that keeps all the devices attached to that audio signal on the same clock. However, poor connections, either from just poor circumstances or too many machines slaved off the main digital output (e.g. - patchers in a chain at a show), can cause jitter to occur as the sync is lost. This causes errors in the datastream, which is a big problem.

On voice calls, the packet inter-arrival variability caused by queuing delays and congestion in the network; the difference between when a packet is expected to arrive and when it actually is received. Jitter causes discontinuity in the real-time voice stream, which we hear as a choppy audio signal. It is a variable component of the total end-to-end network delay.

Jitter is caused by the inability of many CD-ROM drives to accurately seek a specific sector on an audio CD therefore resulting in pops or clicks when listening to the ripped audio track.

Audio: distortion that occurs during digital audio extraction ( ripping) or conversion to analog. Jitter correction helps restore the audio to its original condition. Video: distortion caused by intermittent variations in the characteristics (such as frequency, amplitude, etc.) of a signal.

Flickering on a display screen. Jittering can be caused by (a) a number of hardware problems, such as a slow refresh rate, a bad connection between the video adapter and monitor, a hardware malfunction in the monitor, or poor synchronization in the signals being sent; (b) a nearby electrical conduit or transformer creating a higher-than-usual local magnetic field level. Can also be referred to as packet jitter. (Also see Belch)

Unwanted variations in binary signals leading and trailing edges caused by noise.

Aka. phase jitter, caused by power line harmonics and perceived in the form of minor phase changes.

A variation in the delay of received packets.

Irregular random variations in a radio signal. [H76

A term used to describe variations in the intervals, frequencies, and amplitudes being used to transmit data packets through a stream.

A slight movement of a transmission signal in time or phase, which can introduce errors and loss of synchronization for high-speed, synchronous communications. See phase jitter.

The variation in the amount of Latency among Packets being received

The distortion of a signal as it is propagated through the network, where the signal varies from its original reference timing and packets do not arrive at its destination in consecutive order or on a timely basis, i.e. they vary in latency. Jitter is also referred to as delay variance. This distortion is particularly damaging to multimedia traffic

Noise on a communications line which is based on phase hits, causing potential phase distortions and bit errors.

A tendency towards lack of synchronization caused by electrical changes. Technically the unexpected (and unwanted) phase shift of digital pulses over a transmission medium. A discrepancy between when a digital edge transition is supposed to occur and when it actually does occur - think of it as nervous digital, or maybe a digital analogy to wow and flutter.

deviation from the ideal timing of an event. The reference event is the differential zero crossing for electrical signals. Jitter is composed of both deterministic and Gaussian (random) content.

The slight movement of a transmission signal in time or phase that can induce errors and loss of synchronization in high-speed synchronous communications.

The short-term variation of timed events

Interline transfer CCD cameras employ columns of pixels separated by columns of storage elements. Signals impinging on the CCD sensor may fall on a pixel or on the space between pixels. Statistically speaking, the latter case may cause a response in the pixel to the immediate left or the immediate right of the space. Due to the standard CCD scan frequency of 60Hz, such a static image will exhibit jitter between the two pixels in question over time. Jitter, therefore limits the accuracy of video measurement to at least two pixel separations in monochrome cameras.

Signal timing displacement from its ideal location

Timing jitter is the short-term variation of a digital signal's significant instant from their ideal positions in time, where short term implies phase oscillations of frequency greater than or equal to 10Hz.  Significant instants include for instance, optimum sampling instants.  Long-term variations, where the variations are of frequency less than 10Hz, are called wander.

The variation in timing and/or displacement upon transmission or arrival of digital signal. High Jitter can severely degrade the performance of an otherwise ideal system by introducing unwanted noise at the receiver

Refers to non-uniform delays that can cause packets to arrive and be processed out of sequence.

the instability in the timing of a digital signal waveform associated with the loss of synchronization with a standard clock cycle; less is better.

The result of a change in latency or the tendency towards lack of synchronization caused by mechanical or electrical changes. Technically, jitter is the phase shift of digital pulses over a transmission medium.

Small, rapid variations in a waveform due to mechanical disturbances or to changes in the characteristic of components. Supply voltages, imperfect synchronizing signals, circuits, etc.

Analogue communication line distortion caused by a variation of signals from its reference timing positions. Jitter can also cause data loss, particularly at high speeds.

Jitter is the variation in the time between packets arriving, caused by network congestion, timing drift, or route changes. A jitter is normally quoted when circuits will be used for VoIP applications.

The variation in the time between the arrival of packets caused by network congestion, timing drift, or route changes.

The deviation of a transmission signal in time or phase. It can introduce errors and loss of synchronization in high speed synchronous communications.

random variation in the timing of a signal

Small and rapid variations in the timing of a waveform due to noise, changes in component characteristics, supply voltages, imperfect synchronizing circuits, etc. See also DDJ, DCD, and RJ.

1. Instability of the signal or trace of a cathode-ray tube. 2. Small rapid variations in a waveform due to deliberate or accidental electrical or mechanical disturbances or to changes in the supply voltages, in the characteristic of components, etc.

Variations in arrival time of data packets.

Small random variation introduced into the value of a timer to prevent multiple timer expirations from becoming synchronized. In real-time applications such as VoIP and video, variation in the rate at which packets in a stream are received that can cause quality degradation.

An error condition caused by a signal being out of synchronization with other devices. Go Top

An insidious form of distortion that can occur with digital audio and which is caused by inaccuracies in the clock which is used to regulate the conversion of data into analogue audio.

A dithering in time of a pulse or pulse train. Clock jitter is a tremendous problem in high-speed systems, where even 1 ns of jitter in a signal propagated all over a PCB can cause crashes.

A measure of the variation in delay (latency, or response time). Especially key for Voice and streaming services.

In electronics and telecommunications, jitter is an abrupt and unwanted variation of one or more signal characteristics, such as the interval between successive pulses, the amplitude of successive cycles, or the frequency or phase of successive cycles. Jitter is a significant factor in the design of almost all communications links (e.g. USB, PCI-e, SATA, OC-48).

Varying pitch in the voice, which causes a rough sound. Compare to shimmer, which describes varying loudness in the voice.