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--- en:projects:mth:lcm2 [2007/11/28 08:24]
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+++ en:projects:mth:lcm2 [2009/05/15 10:41] (current)
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-Master thesis project: 2008-2009
+Master thesis project:
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-====   RadioStress   ====
+====   ShapeNoise   ====
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-Digital emulation of non-linear and linear distortions caused by Analog/RF devices involved in wireless transmissions
+Generation of a noise signal with user-defined spectrum mask for spurious signals emulation in wireless transmissions.
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 **Background:**\\
-By nature, Analog/RF devices are not perfect and show both non-linear distortions in time domain (amplitude and phase of output signal are not exactly following amplitude and phase of input signal) and linear distortions in frequency domain (amplitude and phase frequency response is not perfect).
+Spectrum occupancy by other services and unwanted impairments (both in-channel and adjacent) is one of the major difficulties of wireless transmissions.
-Such imperfect characteristics constitute a limiting factor to wireless digital transmission systems performances. However, the influence and acceptable limits for those distortion effects are quite difficult to quantify in practise since real Analog/RF devices characteristics cannot simply be tuned on demand for such test purposes.
+A way to characterize the influence and acceptable limits for a transmission system regarding this spurious spectrum environment is to generate signals with several specific generators/modulators and combine them with the useful signal. This is efficient but requires a lot of equipment, usually expensive and difficult to setup.
-This is why a digital system capable of emulating and generating adjustable/calibrated distortion effects is of prime interest to quantify digital transmission systems requirements in terms of Analog/RF devices performances and quality.
+Another much more simple way to achieve similar work and results is to generate a pseudo-random signal having a spectrum mask representative of all impairment signals. This can be achieved in digital domain by appropriate FIR filtering of some white Gaussian noise.
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 **Objective:**\\
-The project consists in developing a real-time digital processing solution which can be inserted between a transmitter and a receiver at baseband level in order to simulate the non-linear and linear distortion effects of various Analog/RF devices (amplifiers, filters, antennas, etc.) having influence on transmission.
+The project mainly consists in finding a global solution to reproduce any type of arbitrary user-defined spectrum mask / frequency response curve (low pass, high pass, band pass, notch and more complex shapes) in the best possible way with a FIR filter.
-A first step is to develop an off-line PC software enabling to create AM-AM (Amplitude-to-Amplitude) and AM-PM (Amplitude-to-Phase) non-linear response curves in time domain through interpolation from user set of points.
+A first step is a theoretical analysis to dimension filter coefficients (taps) number and precision according to target response curve characteristics and accuracy.
-A second step is to implement real-time corresponding non-linear distortion block as real/imaginary processing and LUTs (Look-Up-Tables) on an hardware FPGA-based (programmable component) platform.
+A second step is to develop an off-line PC software enabling to generate a frequency response curve template (through an interpolation from a user set of point) and to calculate filter coefficients accordingly.
-A third step is to develop an off-line PC software enabling to create amplitude and phase linear response curves in frequency domain, still through interpolation from user points.
+A third step is to implement a real-time parametrizable FIR filter on an hardware FPGA-based (programmable component) platform and to verify correct operation for various template curves.
-A fourth step is to implement real-time corresponding linear distortion block as a parametrizable FIR filter on the hardware platform.
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 **Deliverables:**\\
-- Visual C++ modules with graphic user-interface for response curves capture, LUTs coefficients generation and FIR filter coefficients calculation.\\
+- Preliminary theoretical analysis report.\\
-- VHDL modules for real-time distortion blocks implementation.\\
+- Visual C++ module with graphic user-interface for filter response curve capture and FIR filter coefficients calculation.\\
+- VHDL module for real-time filters implementation.\\
 - Final project report (diploma report).
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 **Organization:**\\
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 ** Comment:**\\
 This project constitutes a very good pre-professional experience through the skills it will enable to enrich (FPGA/ASIC development and PC user-interface development are commonly and highly requested by industry) and through the fact that student(s) will collaborate to a real industrial project.
-\\
+This project can be achieved by 1 student or can be merged with the “RadioStress” project in order to constitute a 2 students team.
+\\
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 **Prerequisites:**\\
-- Electronics, Signal Processing, Telecommunications\\
+- Mathematics, Electronics, Signal Processing, Telecommunications\\
 - Visual C++ programming on PC environment\\
 - VHDL language (preferable but not mandatory)
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 **Supervisor:**\\
-Jean-François Csomo
+Jean-François Csomo, DreamCom
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+\\
 **Professor:**\\
 Prof. Bixio Rimoldi, tel: 32679, office: INR 111, bixio.rimoldi@epfl.ch
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-[[en:projects:2008-2009:mtp|back to master thesis projects menu]]
+[[en:projects:2007-2008:mtp|back to master thesis projects menu]]