Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Demodulation


In the News (Mon 22 Jul 19)

  
  Demodulation - Wikipedia, the free encyclopedia
Demodulation is the act of removing the modulation from an analog signal.
Another one is to use two AM demodulators, one tuned to the high end of the band and the other to the low end, and feed the outputs into a difference amp.
Another is to feed the signal into a phase-locked loop and use the error signal as the demodulated signal.
en.wikipedia.org /wiki/Demodulation   (169 words)

  
 * Demodulation - (Computing): Definition
For example, in a radio broadcast using the audio signal is transmitted as the mean amplitude of a radio-frequency...
Demodulation is the process of decoding an analog signal into digital data.
A process of converting signals sent over a telephone line into form so that they can be processed by a receiving computer, or more widely in telecommunications, any time analog signals are digitised...
en.mimi.hu /computing/demodulation.html   (195 words)

  
 Demodulation   (Site not responding. Last check: 2007-11-07)
Demodulation is the act of removing the modulation from ananalog signal.
One is to use two AM demodulators, onetuned to the high end of the band and the other to the low end, and feed the outputs into a difference amp.
Another is to feedthe signal into a phase-locked loop and use the error signal asthe demodulated signal.
www.therfcc.org /demodulation-20257.html   (104 words)

  
 Demodulation   (Site not responding. Last check: 2007-11-07)
To demodulate an AM signal, pass it through a diode rectifier.
One is to use two AM demodulators, one tuned to the high end of the band and the other to the low end, and feed the outputs into a difference amp.
Employs fast demodulation techniques in fiber optical data acquisition.
www.serebella.com /encyclopedia/article-Demodulation.html   (178 words)

  
 Documentaion for SBDSP - SoundBlaster APT Demodulation Program This program and documentat   (Site not responding. Last check: 2007-11-07)
Demodulation converts the recorded values of the samples of the 2400 Hz APT sine wave into their corresponding pixel values.
All the demodulation software then has to do in order to convert the recorded APT samples into their pixel values is look up the proper table entry.
Using the SoundBlaster for APT demodulation presents two main types of problems: 1) Sample inaccuacies and offsets 2) Clock rate and missing sample errors Sampling a perfect sine wave with a perfect board in a perfect world should yield a series of samples with an average sample value of zero.
www.skepticfiles.org /cowtext/comput~1/drigsb.htm   (2489 words)

  
 Digital demodulation, DPSK and MSK   (Site not responding. Last check: 2007-11-07)
The method of demodulation is an important factor in determining the selection of a modulation scheme.
There are two types of demodulation which are distinguished by the need to provide knowledge of the phase of the carrier.
Clearly, the consequence for the correct interpretation of the demodulated signal is catastrophic.
www.cs.ucl.ac.uk /staff/S.Bhatti/D51-notes/node14.html   (1041 words)

  
 Demodulation
Describe fm demodulation circuit operation for the phase-shift and gated-beam discriminators and the ratio-detector demodulator.
The term demodulator is used because the demodulation process is considered to be the opposite of modulation.
This demodulator circuit is the equivalent of a wire telegraphy circuit but it has certain disadvantages.
www.tpub.com /neets/book12/51.htm   (1212 words)

  
 [No title]   (Site not responding. Last check: 2007-11-07)
Demodulation of the received signal can be achieved simply by rectification, followed by the use of a capacitor to smooth out the high frequency component:
The output from this simple demodulation circuit is a reasonable approximation to the original audio signal.
Modulation and demodulation are used in the transmission and reception of radio and television signals.
www.coathook.pwp.blueyonder.co.uk /elec/elec7a.htm   (335 words)

  
 PSK modem system with improved demodulation reliability - US Patent 4807251   (Site not responding. Last check: 2007-11-07)
Furthermore, the modem system is such that, on the signal demodulation side, the signal received is divided into two parts, one of which is phase-compared with the other after being delayed as long as the total time of the reference phase parts.
The NRZ signal is obtained by removing DC components from the phase comparator output and is formed with the aid of a flip-flop which receives the output of the phase comparator and, as a clock signal, a signal obtained by delaying the synchronizing signal for a predetermined period of time.
That is, in the demodulation circuit of FIG.
www.patentstorm.us /patents/4807251.html   (5523 words)

  
 Robust digital modulation and demodulation scheme for radio communications involving fading - US Patent 6351498   (Site not responding. Last check: 2007-11-07)
A digital modulation and demodulation scheme for radio communications which is capable of reducing errors due to fading while maintaining the characteristic of the M-ary modulation and demodulation scheme that it is robust against interferences.
There are various known schemes for digital modulation and demodulation for radio communications between a terminal and a base station such as those of the mobile communication, and the M-ary modulation and demodulation scheme using orthogonal codes is one such scheme which is attracting much attentions recently.
As for the multi-valued modulation and demodulation method, it is possible to use various known methods besides the multi-valued FSK energy detection, such as the multi-valued PSK synchronous detection and the 16 QAM (Quadrature Amplitude Modulation) pilot synchronous detection.
www.patentstorm.us /patents/6351498.html   (7482 words)

  
 Bearing Demodulation/Enveloping   (Site not responding. Last check: 2007-11-07)
This technique is derived from demodulating the high resonant frequency created by the impacts which are generated by the interactions between the rolling element and the defects such as pittings on raceways.
The demodulated spectrum will highlight the bearing defect frequencies which will not be buried under running speed harmonics and low frequency components.
The level of noise floor and the relative amplitude between the peaks of defect frequency and the mean noise floor indicates the severity.
home1.pacific.net.sg /~tyhum/demod.htm   (229 words)

  
 [No title]   (Site not responding. Last check: 2007-11-07)
Amplitude demodulation is one of the two methods by which excited state lifetimes may be investigated in the frequency domain.
The purpose of having amplitude demodulation measurement capability is to obtain information that supplements, rather than replaces, that obtained by the phase-shift method alone.
The goal of the present work is to explore the problems involved in amplitude demodulation measurements in flow (using digital method), through detailed theoretical modeling and use the model to develop a practical method that can be incorporated into a flow cytometer to measure amplitude modulation lifetimes.
fmrc.pulmcc.washington.edu /WebRefs/R395.htm   (234 words)

  
 I/Q BASEBAND DEMODULATION IN THE RASSP SAR BENCHMARK
I/Q BASEBAND DEMODULATION IN THE RASSP SAR BENCHMARK
The in-phase and quadrature demodulation required for the SAR benchmark application is succinctly described in Section 2.1.3 of Benchmark Technical Description-1 (BTD-1)[1].
Prior to the advent of high-speed A/D converters, I/Q demodulation for high-bandwidth waveforms was usually accomplished in the analog domain by a system similar to the one portrayed in block diagram form in Figure 1.
www.ll.mit.edu /llrassp/iqfilter/iqfilter.html   (1576 words)

  
 Demodulation of Cochannel QAM Signals   (Site not responding. Last check: 2007-11-07)
The tentative decisions are formed using a structure consisting of a primary demodulator followed by a secondary demodulator incorporating an adaptive interference canceller.
Signature curves quantifying the symbol error rate of the tentative demodulator as a function of signal-to-noise ratio and signal-to-interference ratio are presented.
This paper proposes a method for improving the performance of a single-input QAM demodulator in the face of cochannel QAM interference by jointly estimating the desired (primary) signal and the interfering (secondary) signal.
www.appsig.com /papers/l813f/813f_1.html   (338 words)

  
 World Intellectual Property Organization   (Site not responding. Last check: 2007-11-07)
If no such demodulation element is found, the controller may re-assign a demodulation element that is assigned to the same base station sector as the survey path if the survey path is more than 3 dB stronger than the current demodulation path.
demodulation element 114 is locked to its current assignment, it writes demodulated symbols to symbol combiner 80, and when it is unlocked, it does not write symbols to symbol combiner 80.
[0087] In a demodulator according to a further embodiment of the invention, the status of whether a demodulation element is locked to its current assignment is decoupled from the status of whether the demodulation element writes demodulated symbols to symbol combiner 80.
www.wipo.int /ipdl/IPDL-CIMAGES/view/pct/getbykey5?KEY=03/07499.030123&ELEMENT_SET=DECL   (8409 words)

  
 美国专利申请公开说明书 20040184379 - Apparatus and method for detecting frame synchronization signal for ...   (Site not responding. Last check: 2007-11-07)
An apparatus and method of detecting a frame synchronization signal, capable of reducing errors in data demodulation in an optical system, are provided.
The frame synchronization signal detection apparatus includes a synchronization signal detector, a main frame synchronization signal generator, a sub frame synchronization signal generator, and an output unit.
The main frame synchronization signal generator stops generating the first insertion synchronization signal, in response to the second valid synchronization signal, and detects and outputs a first valid synchronization signal as an internal frame synchronization signal.
cxp.paterra.com /uspregrant20040184379cn.html   (273 words)

  
 Demodulation   (Site not responding. Last check: 2007-11-07)
One is to use two demodulators one tuned to the high end the band and the other to the end and feed the outputs into a amp.
Another is to feed the signal a phase-locked loop and use the error signal as demodulated signal.
Demodulation system for fiber optic Bragg grating dynamic pressure sensing (SuDoc NAS 1.15:210895)
www.freeglossary.com /Demodulate   (158 words)

  
 1.3.3.9. Complex Demodulation Phase Plot
The complex demodulation phase plot (Granger, 1964) is used to improve the estimate of the frequency (i.e.,
If the complex demodulation phase plot shows lines sloping from left to right, then the estimate of the frequency should be increased.
The complex demodulation phase plot is used to assess whether this estimate is adequate, and if it is not, whether it should be increased or decreased.
www.itl.nist.gov /div898/handbook/eda/section3/compdeph.htm   (235 words)

  
 Citations: The concept of demodulation in theorem proving - Wos (ResearchIndex)   (Site not responding. Last check: 2007-11-07)
A demodulator is an equality axiom t 1 = t 2 where t 1 ; t 2 are terms.
Applying a demodulator to an atom in a formula in which the term t 1 occurs yields a new formula F 0 where t 1 has been replaced by t 2, possibly by substituting terms for variables appearing in t 1.
Specifically, if the following demodulator list is included in the input, where T is interpreted as true, then all clauses containing as a proper subexpression i(t; t) for some term t are immediately purged.
citeseer.ist.psu.edu /context/109163/0   (2243 words)

  
 1.3.3.8. Complex Demodulation Amplitude Plot
The complex demodulation amplitude plot (Granger, 1964) is used to determine if the assumption of constant amplitude is justifiable.
The complex demodulation amplitude plot is demonstrated in the beam deflection data case study.
Complex demodulation amplitude plots are available in some, but not most, general purpose statistical software programs.
www.itl.nist.gov /div898/handbook/eda/section3/compdeam.htm   (275 words)

  
 ECE 4660: Lab 2-Synchronous and Asynchronous Demodulation
Objective: The objective of this lab is to deepen students understanding of synchronous and asynchronous demodulation principles for amplitude modulation.
Demodulation by multiplication with a complex exponential will require four real multiplies and two adds.
Complete the asynchronous demodulator by designing the low pass filter and filtering z(t)-A to produce w(t).
www.engineering.usu.edu /classes/ece/4660/lab2/lab2b.html   (711 words)

  
 DEMODULATOR   (Site not responding. Last check: 2007-11-07)
Als Demodulator bezeichnet man die Einrichtung zur Gewinnung der Modulation aus einer Träger-Schwingung.
Ein Demodulator befindet sich z.B. in einem Radio-Empfänger.
Zur Demodulation amplitudenmodulierter Schwingungen wird das Signal gleichgerichtet und anschließend an einen RC-Glied zur Unterdrückung hochfrequenter Restschwingungen vorbeigeleitet.
www.toonorama.com /encyclopedia/D/Demodulator   (94 words)

  
 Demodulation Document   (Site not responding. Last check: 2007-11-07)
First, FM signal demodulation is briefly reviewed, then the NSI signal digitization process as well as the relative merits of such a process are discussed.
The demodulator's numerical processing hardware receives a binary count representation of FM data from the zero-crossing count circuitry in the IF strip, performs an estimation process on successive samples, subsequently recovering modulating amplitude information.
NSI's Digital Demodulation system is superior to conventional demodulation methods due to the linear nature of digital signal processing and its inherently high level of bit-resolution.
www.peganet.net /numatech/lstsqfit.html   (1905 words)

  
 Radio-Electronics.Com :: Synchronous demodulation / detection
For the signal to be demodulated correctly the carrier should be present at the required level.
It can be seen that the signal covers a definite bandwidth, and the effects of fading may result in the carrier and possibly one of the sidebands being reduced in level.
As the demodulator is what is termed a coherent modulator it only sees the components of noise that are in phase with the local oscillator.
www.radio-electronics.com /info/receivers/synchdet/sync_det.php   (1075 words)

  
 PSK signal demodulation method and apparatus - Patent 5727027   (Site not responding. Last check: 2007-11-07)
In a PSK signal demodulation method of demodulating a received signal by sampling processing, one sampling interval is time-divided.
Such a method, however, requires the multiple frequency converters 71, the multiple demodulators 72 each constituted by a filter, a clock recovery circuit, a carrier recovery circuit, and the like, an optimum demodulation detection means constituted by the correlators 73 and the detection control section 75.
This demodulation circuit is designed to achieve carrier/clock phase lock throughout a wide frequency range in real time at a high speed in satellite communication of low-speed transmission of a PSK modulated signal.
www.freepatentsonline.com /5727027.html   (3610 words)

  
 TR0406   (Site not responding. Last check: 2007-11-07)
The demodulated analytic signal is projected onto the time-frequency plane so that, as closely as possible, each component contributes exclusively to a different `tile’ in a wavelet packet tiling of the time-frequency plane, and at each time instant the contribution to each tile definitely comes from no more than one component.
A single reverse demodulation is then applied to all projected components.
The validity and practical utility of the resulting expression for the variance of the estimated instantaneous frequency is demonstrated via a simulation experiment.
www.ma.ic.ac.uk /statistics/techreports/TR0406.htm   (187 words)

  
 Demodulation Document   (Site not responding. Last check: 2007-11-07)
In a previous report, we discussed the details of demodulation of an FM signal in a DSP Environment, and presented the details of a "Linear" Data Fit Estimation process as well a "Least Squares" Data Fit Estimation process.
In the implementation of a "Reciprocal Count Scaling" demodulation process, an exact analytic solution is realized, and guarantees -- in terms of Signal-to-noise ratio, Total Harmonic Distortion, and pure scaling accuracy -- the most accurate results attainable from a system of this type.
As concerns NSI's demodulation process, consider two successive zero crossing events in a sinusoidal waveform; An average instantaneous frequency value, F(t), can be found by taking the reciprocal of twice the measured period, T(t), between the zero-crossings...
www.peganet.net /numatech/recipfit.html   (1072 words)

  
 SurfWax: News, Reviews and Articles On Demodulation
If the purchase goes through, Intel said Zarlink's demodulation and tuner technologies will be made into building block modules and sold to consumer device manufacturers similar to the Oplus MN 301, a system-on-a-chip processor.
DiBcom's demodulation chip, often paired with a separate tuner IC developed by companies such as Motorola, is being used in a number of international DVB-H trials.
The new signal reception chip is more than 100 times as sensitive as devices made to date, enabling even people on speeding trains to receive and watch digital television broadcasts on their phone screens.
news.surfwax.com /telecom/files/Demodulation.html   (1191 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.