AN2832 Freescale Semiconductor / Motorola, AN2832 Datasheet
AN2832
Related parts for AN2832
AN2832 Summary of contents
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... Impulse Response ...................................................6 2.2 Generating the Training Signal ...............................6 2.3 Transmitting the Training Signal ............................7 (n) by 2.4 Calculating the Impulse Response ..........................8 t 2.5 Emulating Target Impulse Responses .....................8 2.6 Considerations for Real-Time Implementation .......8 2.7 Typical Results ........................................................9 3 Remote Diagnostics on StarCore ..........................11 3.1 System-Level Optimization ..................................11 3.2 Kernel-Level Optimization ...................................12 4 Conclusion ............................................................13 5 References .............................................................13 AN2832 Rev. 1, 9/2004 ...
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Basics of Remote Diagnostics 1 Basics of Remote Diagnostics Remote diagnostic tests are becoming important maintenance applications in packet telephony systems for monitoring and sometimes correcting anomalies that affect performance of voice or data communication services [1], [2]. Maintenance tests ...
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The method discussed here for estimating and dynamically emulating impulse response of hybrid circuits is motivated by channel estimation techniques in ADSL systems [5], which have been extensively employed in the field and proven to be accurate and reliable. The ...
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Basics of Remote Diagnostics TS0 TS1 Central Office Simulator TS2 TS3 Figure 3. Multi-Channel HCID Implemented on the MSC8101ADS Board Packet Telephony Remote Diagnostics on the StarCore SC140 Core, Rev Debug T1 Framer T1 MSC8101ADS Board Freescale Semiconductor ...
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Remote Diagnostic Architecture Figure 4 shows a top-level view of the remote diagnostic device, with respect to the hybrid circuit and network echo canceller (ECAN). The device monitors the r measurements requested from the communication network. y(n) w(n) + ...
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Remote Diagnostic Architecture 2.1 Estimating the FFT-Based Hybrid Circuit Impulse Response The impulse response of hybrid circuits is estimated with an FFT-based channel identification scheme similar to the method used in ADSL systems, as shown in Figure 5. Serial to ...
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Obtaining the Φ values requires the use of a random number generator. A standard code to generate random k numbers can be found in [8]. This reference provides a number of random number generators, from which uniform and identically distributed ...
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Remote Diagnostic Architecture When the receive frame is obtained used to compute the average, that is, the low-pass filter (LPF), of the receive signal (y(n)). In this computation, the receive samples from at least the first two frames ...
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ECAN must be disabled (see Figure 4). Notice that the signals are converted from serial to parallel (S/P) and from parallel to serial (P/S), as needed. Compute the DFT of x(n), which is typically pre-computed, and y(n FFT[x(n)] ...
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Remote Diagnostic Architecture The training signal is composed 100 periods of 128 ms frames at a sampling rate of 8 KHz (that is 128 × 1024 samples). Two estimates of echo return loss ...
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Remote Diagnostics on StarCore This section describes an implementation of the remote diagnostic architecture presented in Section Freescale StarCore MSC8101 DSP. Extensive real-time tests demonstrated that the remote diagnostic software requires fewer than 2.0 million cycles ...
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Remote Diagnostics on StarCore During FFT/IFFT operations, the received signal and estimated channel impulse response are purely real signals; that is, their imaginary portions are all zeroes. To increase computational efficiency, the real data set can be split into two ...
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much more efficient to compute two data points in parallel. Another point of computation is N/2 – k, which shares the same twiddle factor as point ⁄ N ...
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... A. V. Oppenheim, R.W. Schafer, and J. R. Buck, Discrete-Time Signal Processing, Prentice Hall, 2nd edition, 1999. [10] E. Roy and D. Crawford, Introduction to the StarCore SC140 tools: An approach in Nine Exercises, Freescale Semiconductor, Application Note, AN2009/D, 2001. Packet Telephony Remote Diagnostics on the StarCore SC140 Core, Rev. 1 ...
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NOTES: Packet Telephony Remote Diagnostics on the StarCore SC140 Core, Rev. 1 Freescale Semiconductor References 15 ...
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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 AN2832 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 ...