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Design and Implementation of Numerical Linear Algebra Algorithms on Fixed Point DSPs


Numerical linear algebra algorithms use the inherent elegance of matrix formulations and are usually implemented using C/C++ floating point representation. The system implementation is faced with practical constraints because these algorithms usually need to run in real time on fixed point digital signal processors (DSPs) to reduce total hardware costs. Converting the simulation model to fixed point arithmetic and then porting it to a target DSP device is a difficult and time-consuming process. In this paper, we analyze the conversion process. We transformed selected linear algebra algorithms from floating point to fixed point arithmetic, and compared real-time requirements and performance between the fixed point DSP and floating point DSP algorithm implementations. We also introduce an advanced code optimization and an implementation by DSP-specific, fixed point C code generation. By using the techniques described in the paper, speed can be increased by a factor of up to 10 compared to floating point emulation on fixed point hardware.


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Correspondence to Zoran Nikolić.

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Nikolić, Z., Nguyen, H.T. & Frantz, G. Design and Implementation of Numerical Linear Algebra Algorithms on Fixed Point DSPs. EURASIP J. Adv. Signal Process. 2007, 087046 (2007).

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