How Can You Minimize The Quantization Error
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Methods To Reduce Quantization Error In Pcm
NO RATINGSLogin to Rate Tweet No matter how many bits an analog-to-digital converter (ADC) provides, the digital output can only approximate the
Quantization Noise In Pcm Can Be Reduced By
original signal. This approximation gives rise to quantization errors, or quantization "noise." The error values fall between ±1/2 the voltage represented by the ADC's least-significant bit (LSB) and they have a fairly uniform distribution within this
Quantization Noise Can Be Reduced By Increasing
range. Although ADCs with higher resolution reduce the quantization errors, they always remain within ±1/2 LSB. You can think of the quantization error as adding white noise to the digitized information. By definition, white noise has a "flat" power spectrum over the fsample/2 bandwidth. So how can a data-acquisition system reduce quantization errors? Because these errors depend only on an ADCs resolution, sampling at a much higher rate than you would normally spreads the the quantization error in an analog-to-digital converter can be reduced by quantization noise over a larger bandwidth. And thus the power density for a fixed bandwidth decreases as fsample increases. In practice, a higher sample rate decreases the quantization noise superimposed on the digital data for the signal you want to measure. But the reduction of the noise comes at a price -- more data to process and the need to digitally filter the data. Doubling the sample rate increases the ADC resolution by 1/2 LSB. This sigma-delta modulator converts an analog-input signal to a stream of logic-1 bits proportional to the signal voltage.
This type of oversampling becomes impractical, though, unless you also use a technique called noise shaping. This technique decreases noise in the bandwidth of interest by "shifting" it to higher frequencies where it has less effect on your signals of interest. Sigma-delta, also called delta-sigma, ADCs provide this function and produce high resolutions for relatively low-frequency signals. A sound card, for example, relies on a sigma-delta converter that oversamples at up to 192 ksamples/sec. Some converters operate at 256 times the Nyquist frequency and provide resolutions of 20 or more bits. The simplest sigma-delta ADC uses a difference amplifier, an integrator, a comparator, and a 1-bit digital-to-analog converter (DAC), as shown in the figure, in what engineers call a sigma-delta modulator. The DACExplore My list Advice Scholarships RENT/BUY SELL MY BOOKS STUDY what is quantization error HOME TEXTBOOK SOLUTIONS EXPERT Q&A TEST PREP HOME ACT PREP to reduce quantization error qe in a pcm system SAT PREP PRICING ACT pricing SAT pricing INTERNSHIPS & JOBS CAREER PROFILES ADVICE EXPLORE MY quantization error pdf LIST ADVICE SCHOLARSHIPS Chegg home Books Study Tutors Test Prep Internships Colleges Home home / study / english / communications / questions and answers http://www.designnews.com/author.asp?doc_id=246011 / the quantization error can be reduced in a pcm ... Question: The quantization error can be reduced in a PCM sig... The quantization error can be reduced in a PCM signal by ____. a increasing the signal voltage b reducing the signal voltage c reducing the number of quantization http://www.chegg.com/homework-help/questions-and-answers/quantization-error-reduced-pcm-signal--increasing-signal-voltage-b-reducing-signal-voltage-q2804434 levels d increasing the number of quantization levels Expert Answer Get this answer with Chegg Study View this answer OR Find your book Find your book Need an extra hand? Browse hundreds of Communications tutors. ABOUT CHEGG Media Center College Marketing Privacy Policy Your CA Privacy Rights Terms of Use General Policies Intellectual Property Rights Investor Relations Enrollment Services RESOURCES Site Map Mobile Publishers Join Our Affiliate Program Advertising Choices TEXTBOOK LINKS Return Your Books Textbook Rental eTextbooks Used Textbooks Cheap Textbooks College Textbooks Sell Textbooks STUDENT SERVICES Chegg Play Chegg Coupon Scholarships Career Search Internships College Search College Majors Scholarship Redemption COMPANY Jobs Customer Service Give Us Feedback Chegg For Good Become a Tutor LEARNING SERVICES Online Tutoring Chegg Study Help Solutions Manual Tutors by City GPA Calculator Test Prep Chegg Plants Trees © 2003-2016 Chegg Inc. All rights reserved. Over 6 million trees planted
components Analog Semiconductors Digital semiconductors Mixed-signal semiconductors Services Software Systems Materials Test & http://mwrf.com/components/reducing-adc-quantization-noise Measurement - analyzers Test & Measurement - generators NewsImage Galleries Products MarketsAutomotive Commercial Defense Industrial Medical Learning ResourcesReferences & Tools RF Essentials Webcasts White Papers 2016 Leaders in Microwaves RF Classics Frequency Allocation Charts Data Sheets Reference Designs Salary Survey Salary Calculator What's the Difference Between... Wireless quantization error Standards 2016 Wall Chart CompaniesCompany Directory CommunityBlogs Contributors Our Editors Interviews Microwave Legends Advertisement Home > Technologies > Components > Reducing ADC Quantization Noise Reducing ADC Quantization Noise Two techniques, oversampling and dithering, have gained wide acceptance in improving the noise performance of commercial analog-to-digital converters. Jun to reduce quantization 17, 2005 Richard Lyons and Randy Yates | Microwaves and RF EMAIL Tweet Comments 0 Download this article in .PDF format This file type includes high resolution graphics and schematics when applicable. Analog-to-digital converters (ADCs) provide the vital transformation of analog signals into digital code in many systems. They perform amplitude quantization of an analog input signal into binary output words of finite length, normally in the range of 6 to 18 b, an inherently nonlinear process. This nonlinearity manifests itself as wideband noise in the ADC's binary output, called quantization noise, limiting an ADC's dynamic range. This article describes the two most popular methods for improving the quantization noise performance in practical ADC applications: oversampling and dithering. Related Finding Ways To Reduce Filter Size Matching An ADC To A Transformer Tunable Oscillators Aim At Reduced Phase Noise Large-Signal Approa
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