
	Where results make sense

Topic: Phase noise

Related Topics

phase transitions

Lunar phase

phase locked loop

phase space

phase modulation

three phase

phase shifts

Three phase electric power

moon phase

phase velocity

Gibbs phase rule

In the News (Sat 28 Nov 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Vectron Products - Phase Noise
		Phase noise is measured in the frequency domain, and is expressed as a ratio of signal power to noise power measured in a 1 Hz bandwidth at a given offset from the desired signal.
		Noise relatively close to the carrier (Region A) is called Flicker FM noise; its magnitude is determined primarily by the quality of the crystal.
		The phase noise test characterizes the output spectral purity of an oscillator by determining the ratio of desired energy being delivered by the oscillator at the specified output frequency to the amount of undesired energy being delivered at neighboring frequencies.
	www.vectron.com /products/appnotes/phase.htm (1159 words)

	Phase noise - Wikipedia, the free encyclopedia
		In an oscillator, phase noise is rapid, short-term, random fluctuations in the phase of a wave, caused by time domain instabilities.
		Phase noise, L(f) in decibels relative to carrier power (dBc) on a 1 Hz bandwidth, is given by:
		(f) is the spectral density of phase fluctuations.
	en.wikipedia.org /wiki/Phase_noise (73 words)

	Radio-Electronics.Com :: Phase Noise and Frequency Synthesizers
		Phase noise is present on all signals to some degree and it is caused by small phase (and hence frequency) perturbations or jitter on the signal.
		If significant levels of phase noise are present on a synthesizer used as a local oscillator in a receiver, it can adversely affect the performance of the radio in terms of reciprocal mixing.
		It has already been mentioned that the level of phase noise changes as the offset from the carrier changes and for "simple" signal sources like crystal oscillators or variable frequency oscillators the phase noise reduces as the frequency from the main carrier is increased.
	www.radio-electronics.com /info/receivers/synth_basics/phase_noise.php (1624 words)

	Phase noise and jitter -- a primer for digital designers (Site not responding. Last check: 2007-11-05)
		Phase noise is usually specified in dBc/Hz at a given offset, where dBc is the level in dB relative to the carrier.
		The phase noise of an oscillator at a given offset is derived from the ratio of the power in a 1-Hz bandwidth at the offset frequency to the total power of the carrier.
		In Figure 2, phase noise is represented by the ratio of the area of the rectangle with 1-Hz bandwidth at offset fm to the total area under the power spectrum curve, approximately the difference in the height of the spectrum at the centre and at fm.
	www.eedesign.com /article/printableArticle.jhtml?articleID=16501598 (2048 words)

	NIST Phase Noise Measurements Group
		The broadband phase noise of the 100 GHz Gunn oscillator is limited by mixer/divider noise, since the 10 GHz reference is a sapphire-loaded cavity oscillator (SLCO) at ultralow phase noise.
		Phase noise at 100 GHz is measured by two nearly identical phase-locked-loops whose loop phase deviations are analyzed simultaneously by means of a cross-spectrum analyzer.
		The broadband noise generated in the mixer and amplifier for one channel is independent of the broadband noise generated in the mixer and amplifier of the other channel.
	tf.nist.gov /phase/100GHz.html (517 words)

	LAB744 - Phase Noise Measurements
		Phase noise is a random modulation of the phase of an oscillator's output due to a variety of internal processes within the oscillator circuit.
		In the frequency domain, phase noise is seen as a broadening of the oscillator signal’s frequency spectrum due to modulation sidebands.
		The phase shift is adjusted to exact phase quadrature indicated by a minimum DC level at the output of the mixer.
	www.lecroy.com /tm/library/labs/lab744?menuid=2 (1226 words)

	Anderson Electronics, Inc. - Tutorial (Phase Noise)
		Phase noise is random phase modulation which is present in quartz crystal oscillator.
		Phase noise is measured in the frequency domain and is measured by beating two oscillators of like design in a double balanced mixer in quadrature.
		Phase noise performance is degraded by frequency multiplication at the rate of 20 log (N) whereas N being the multiplication factor.
	www.aextal.com /tutorial-phase-noise.htm (305 words)

	LO Phase Noise Report
		The LO Phase Noise Report displays the effects of mixer LO noise on the system.
		Noise contributions are based on the mixer(s) having symmetrical upper and lower side-band power spectral density characteristics (additional information regarding SysCalc's SSB noise modeling can be found in Mathematical Definitions and Derivations).; therefore, the total mixer noise power is based on twice the equivalent SSB noise power in the bandwidth defined by the system.
		The interference power level is determined by each Mixer's SSB noise level and the filtering encounter by the interferer.
	www.ardentech.com /WebHelp/Reports/LO_Phase_Noise_Report.htm (1022 words)

	Phase Noise in High-Performance Oscillators - impact of ultralow phase noise oscillators on system performance
		In an oscillator, phase noise is the rapid random fluctuations in the phase component of the output signal.
		Noise has infinite bandwidth, and hence the greater the bandwidth of the instrument being used to measure a carrier frequency with noise, the higher the noise it measures.
		Note that phase noise and jitter are two linked quantities associated with a noisy oscillator, and, in general, as the phase noise increases in the oscillator, so does the jitter.
	rfdesign.com /vlf_to_uhf/time_and_frequency/radio_impact_ultralow_phase (2211 words)

	CSD October 1999 Feature: The Effects of Phase Noise on High-Order QAM Systems
		Phase noise is introduced by the combined effect of the oscillators and synthesizers used in frequency translation of the modulated signal.
		Oscillator phase noise is typically specified by discrete measurements of the oscillator output’s one-sided spectral density.
		(f) is the PSD of the untracked oscillator phase noise, and H(f) is the receiver’s frequency response to phase noise.
	www.commsdesign.com /main/1999/10/9910feat3.htm (2480 words)

	Application Note: VCO
		The source of phase noise in an oscillator is due to thermal and flicker or 1/f noise.
		The phase noise of an oscillator is best described in the frequency domain where the spectral density is characterized by measuring the noise sidebands on either side of the output signal center frequency.
		The phase noise of the VCO is therefore determined primarily by the overall Q of the circuit.
	surf.syr.edu /projects/vco/Phase_Noise.htm (949 words)

	NIST Time and Frequency Metrology Group
		The oscillating, or repeating, signal that is the basis for constructing all signals is a voltage that exactly follows simple periodic sine and cosine functions of time.
		It is worth noting that overall performance of various technologies depends on, and is often limited by, phase and amplitude noise fluctuations in oscillators and frequency synthesizers.
		It engages in many activities to determine the cause of various kinds of noise for the purpose of isolating and reducing it, leading to improved components, instruments and techniques that are often necessary in new applications.
	tf.nist.gov /phase (224 words)

	Techniques for Measuring Phase Noise
		The noise output is typically sent to a low noise amplifier followed by an audio spectrum analyzer, wave analyzer, or filter.
		The phase slope is being checked at only one frequency and there may be a non-flat frequency response, especially if an unusual mixer circuit is used to enhance the phase slope.
		When only close-in noise is to be measured or the noise floor is not pushing the limits of the measurement, it is a good idea to terminate the mixer output with 50 ohms.
	www.wenzel.com /documents/measuringphasenoise.htm (1509 words)

	Phase-Noise Profiles Aid System Testing - phase noise profiles, introducing phase noise, jitter, tolerance, testing, ...
		The noise output is followed by a filter that shapes the noise according to the phase-noise profile required in Figure 1a or 1b.
		For the phase modulator of Figure 1b, a flat phase-noise region is produced by a white Gaussian-noise voltage followed by a digital filter with flat frequency response in the offset frequency of interest (i.e., a bandpass filter).
		The Figure 1a circuit produces phase noise by modulating the VCO tuning input directly, and the Figure 1b circuit generates phase noise with an external phase modulator.
	www.rfdesign.com /vlf_to_uhf/active_components/radio_phasenoise_profiles_aid (1304 words)

	Pseudorange- and Carrier Phase Noise (Site not responding. Last check: 2007-11-05)
		Experience shows, that the noise level of both pseudorange and carrier phase often depends on the satellite elevation: low elevation satellites have a longer path through the atmosphere, and are thus more damped, and can be more noisy because of ionospheric scintillation, and thus deliver more noisy observations than high elevation satellites.
		Remaining errors are the DD receiver noise, and, in case of the carrier phase, the DD cycle ambiguity.
		However, the noise level on a DD is higher than the noise level on an undifferenced observation.
	home.tiscali.nl /~samsvl/noise.htm (484 words)

	VCO Phase Noise Optimization for the MAX2309 - Maxim/Dallas
		LO phase noise on the MAX2309 is improved at 100MHz.
		After measuring phase noise with the modified VCO and loop filter, a second loop filter was evaluated.
		The phase noise was measured and the results are shown in Figure 3 and Figure 4.
	www.maxim-ic.com /appnotes.cfm/appnote_number/1744 (463 words)

	Jitter and Phase Noise
		First, the noise is assumed to be in quadrature (90 degrees out-of-phase) to the main clock sinusoid.
		The ratio of the noise power to the power in the fundamental equals the variance (standard deviation squared) of the phase modulation in units of radians squared.
		Assuming the noise is Gaussian (and not the result of some deterministic, predictable phase wander), one normally figures that if the BER of the system is specified at, say, 1E-12, then it's OK to violate the phase jitter spec one time in 1E12.
	www.sigcon.com /Pubs/news/4_7.htm (1012 words)

	Phase Noise and Allan Deviation Test Sets
		Symmetricom’s state-of-the-art phase noise and Allan deviation (ADEV) test sets enable customers to make accurate measurements between 1 — 30MHz quickly and easily.
		Since its introduction, the 5110A has grown to be recognized as the worldwide standard for ADEV measurements.
		Typically used to characterize high precision oscillators and atomic clocks, Symmetricom's test sets are designed to make accurate phase noise and ADEV measurements easily.
	www.symmttm.com /products_pn_adev_test_sets.asp (310 words)

	phase noise oscillator Search : Products, Services, Companys, Resources, News and Information about phase noise ...
		Choose an active.....s equation [1] in respect to oscillator phase noise..
		Phase Locked Oscillators Phase Locked Oscillators for Military and Airborne Applications November 1, 1995 Wenzel Associates introduces a series of phase locked oscillators for military and...
		Phase Noise, Harmonics and Sub-Harmonics.....to noise ratio of...
	www.uwbtalk.com /archive/phase-noise-oscillator.html (335 words)

	metas: Electricity - Phase Noise (Site not responding. Last check: 2007-11-05)
		The relative importance of the measurement and specification of phase noise has increased considerably with recent developments in telecommunications, radar applications and metrology.
		Frequency sources based on quartz oscillators are greatly affected, since oscillator noise limits channel capacity of telecommunication systems and compromises the accuracy of measuring systems.
		The measurement system provided by METAS is based on a commercial phase noise measuring system, which can analyse carrier frequencies in the range 5 GHz...
	www.metas.ch /en/labors/2/24phasenoise.html (206 words)

	Phase Noise and TD-SCDMA UE Receiver - Maxim/Dallas
		This action is caused by the gain varying in response to the noise on their power supply lines.
		To accomplish this, the phase noise specification should be improved by 3dB at 1KHz, 10KHz, 20KHz offset.
		This RMS phase noise is acceptable, mainly due to the low noise of the MAX8878.
	www.maxim-ic.com /appnotes.cfm/appnote_number/1824 (1243 words)

	Simulating Phase Noise with NoiseCons
		Rather than compute the single sideband phase noise, the noise voltage is computed both at the carrier frequency minus the offset frequency and at the carrier frequency plus the offset frequency.
		If the phase noise results from this simulation at the seventh harmonic and the phase noise results around the fundamental are compared, the phase noise is seen to be increased 20 log(7), or 16.9 dB, as expected.
		The results are present as an absolute noise voltage spectrum around the carrier frequency, with the results extending from the carrier frequency minus the largest offset frequency to the carrier frequency plus the largest offset frequency.
	eesof.tm.agilent.com /docs/adsdoc15/cktsim/ck103.html (936 words)

	Phase Noise
		All are frequency or phase modulated by random noise to some extent.
		phase noise is a function of the stability of the LO.
		Phase noise is displayed only when a signal is displayed far
	www.spectrum-analyzer.info /Spectrum_Phase_noise.aspx (317 words)

	Oscillator Phase Noise: A Tutorial - Lee, Hajimiri (ResearchIndex) (Site not responding. Last check: 2007-11-05)
		Abstract: Linear time-invariant (LTI) phase noise theories provide important qualitative design insights but are limited in their quantitative predictive power.
		Part of the difficulty is that device noise undergoes multiple frequency translations to become oscillator phase noise.
		0.6: Phase Noise in LC Oscillators - Konstantin Kouznetsov And
	citeseer.ist.psu.edu /lee00oscillator.html (390 words)

	Low phase noise crystals :: precision crystals from International Crystal
		International Crystal Manufacturing's (ICM) low phase noise crystals are specially designed to have as pure a spectral signal as possible.
		Low phase noise crystals are often used in critical applications such as communications, microwave, wide band data transmission, and radar.
		Specific Phase Noise Requirements normally specified as a level at 10Hz, 100 Hz, 1000 Hz from the main frequency.
	www.icmfg.com /lowphasenoise_crystals.html (148 words)

	phase noise math question (Site not responding. Last check: 2007-11-05)
		The conversion from phase noise to jitter is almost simple.
		Sounds easy until you find out that phase noise is almost always specified as straight line segments (good) on dB vs log frequency graph paper (bad).
		The phase noise characterises the signal, not the way that the signal was generated, so "no PLLs" is irrelevant, although they often will cause bumps in the noise spectrum around the loop bandwidth.
	shoko.calarts.edu /pipermail/music-dsp/1998-September/020857.html (665 words)

	Physical processes of phase noise in differential LC oscilla (Site not responding. Last check: 2007-11-05)
		There is an unprecedented interest among circuit designers today to obtain insight into the mechanisms of phase noise in LC oscillators.
		Next, the upconversion of flicker noise into phase noise is traced to mechanisms first identified in the 1930's, but apparently since forgotten.
		Unlike thermally induced phase noise, which appears as phase modulation sidebands, flicker noise is shown to upconvert by bias-dependent frequency modulation.
	www.edaboard.com /ftopic78087.html (256 words)

	Phase Noise Suppression in OFDM Using a (ResearchIndex) (Site not responding. Last check: 2007-11-05)
		Phase Noise Suppression in OFDM Using a (2003)
		Phase noise causes constellation rotation, the so called common phase error (CPE), and intercarrier interference (ICI).
		20 Phase Noise in Oscillators: A Unifying Theory and Numerical..
	citeseer.ist.psu.edu /687904.html (348 words)

Try your search on: Qwika (all wikis)