An Improved Quality Adaptive Rate Filtering Technique Based on the Level Crossing Sampling

Mostly the systems are dealing with time varying signals. The Power efficiency can be achieved by adapting the system activity according to the input signal variations. In this context an adaptive rate filtering technique, based on the level crossing sampling is devised. It adapts the sampling frequency and the filter order by following the input signal local variations. Thus, it correlates the processing activity with the signal variations. Interpolation is required in the proposed technique. A drastic reduction in the interpolation error is achieved by employing the symmetry during the interpolation process. Processing error of the proposed technique is calculated. The computational complexity of the proposed filtering technique is deduced and compared to the classical one. Results promise a significant gain of the computational efficiency and hence of the power consumption.

Authors:

• Saeed Mian Qaisar
• Laurent Fesquet
• Marc Renaudin

Keywords:

• Level Crossing Sampling
• Activity Selection
• Rate Filtering
• Computational Complexity
• Interpolation Error.

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