AN2834 Freescale Semiconductor / Motorola, AN2834 Datasheet
AN2834
Related parts for AN2834
AN2834 Summary of contents
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... ALC specification. © Freescale Semiconductor, Inc., 2004. All rights reserved. Rev. 1, 9/2004 CONTENTS 1 Basics of Automatic Level Control .........................2 2 Architecture .............................................................4 3 Automatic Level Control on StarCore ....................6 3.1 Estimation of Signal Levels ....................................6 3.2 Gain Adaptation ......................................................7 3.3 Auxiliary Functions .................................................7 4 G.169 Compliance Test Results ..............................9 5 Conclusion ............................................................10 6 References .............................................................10 AN2834 ...
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Basics of Automatic Level Control 1 Basics of Automatic Level Control ALC, sometimes called automatic gain control (AGC well-known application in communication systems with a given input signal conditioned to produce an output signal as constant in amplitude ...
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A small adaptation step-size is typically required to avoid a level clipping effect on the signal. However, a very small step-size leads to undesirable ...
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Architecture For example, the bias for a white Gaussian noise with zero mean and unit variance is as follows, which clearly converges to one for values of a close to one. 2 Architecture One major G.169 requirement to constrain the ...
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Use the control signal Compute the total gain signal: g Generate the output signal: y(n) = min{max{g 9. Estimate the ALC output signal level: P 10. Repeat steps 1–10 for new samples of x(n). 11. Figure 1 ...
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Automatic Level Control on StarCore –15 • – 2 max –8 • – 2 –(20 + 6.1824)/10 • min –15 • = 8096 2 • Automatic Level ...
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Estimation of Signal Levels The ALC device requires level estimations of three signals: • Send-in signal x(n). in • Send out signal y(n). out • Receive-in signal z(n). in The filtering process for ...
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Automatic Level Control on StarCore Table 1 lists the coefficients of the fourth-order polynomial. The MMSE coefficients are optimized for values of y between –1 and 0 (notice that the exponent Taylor expansion (c = (ln2) / ...
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Figure 4 shows the dynamic signal levels and total gain g where the target reference level is set –10 –20 –30 –40 – –5 –10 –15 0 0.1 Figure 4. Dynamic Signal Levels ...
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Conclusion Table 3 summarizes the test results, along with the corresponding test controls and test conditions. A sinusoid wave with a frequency of 1004 Hz was selected as the test signal. The tests indicate that selecting different signal types does ...
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NOTES: Packet Telephony Automatic Level Control on the StarCore SC140 Core, Rev. 1 Freescale Semiconductor References 11 ...
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... P.O. Box 5405 Denver, Colorado 80217 1-800-441-2447 or 303-675-2140 Fax: 303-675-2150 LDCForFreescaleSemiconductor@hibbertgroup.com AN2834 Rev. 1 9/2004 Information in this document is provided solely to enable system and software implementers to use Freescale Semiconductor products. There are no express or implied copyright licenses granted hereunder to design or fabricate any integrated circuits or integrated circuits based on the information in this document ...