Two-Path All-pass Based Half-Band Infinite Impulse Response Decimation Filters and the Effects of Their Non-Linear Phase Response on ECG Signal Acquisition

This paper is based on the novel use of a very high fidelity decimation filter chain for Electrocardiogram (ECG) signal acquisition and data conversion. The multiplier-free and multi-stage structure of the proposed filters lower the power dissipation while minimizing the circuit area which are crucial design constraints to the wireless noninvasive wearable health monitoring products due to the scarce operational resources in their electronic implementation. The decimation ratio of the presented filter is 128, working in tandem with a 1-bit 3rd order Sigma Delta (ΣΔ) modulator which achieves 0.04 dB passband ripples and -74 dB stopband attenuation. The work reported here investigates the non-linear phase effects of the proposed decimation filters on the ECG signal by carrying out a comparative study after phase correction. It concludes that the enhanced phase linearity is not crucial for ECG acquisition and data conversion applications since the signal distortion of the acquired signal, due to phase non-linearity, is insignificant for both original and phase compensated filters. To the best of the authors’ knowledge, being free of signal distortion is essential as this might lead to misdiagnosis as stated in the state of the art. This article demonstrates that with their minimal power consumption and minimal signal distortion features, the proposed decimation filters can effectively be employed in biosignal data processing units.

The world without outside

The world is all that there is. In the world, ontology and epistemology coincide. The thing and the perspective are part of it, scale is ingested in its multiplicity, communication stops at the world's edge. By reading together Deleuze and Guattari's plane of immanence and Niklas Luhmann's proto-global concept of Weltgesellschaft (“world society”), I suggest a conceptualisation of the world as the materiality of the multiple spaces of creation in an insular, all-inclusive immanence. Deprived of an outside, the world pushes its own understanding of circumference through, first, the expansion of its own limits through the process of worlding, and, second, the multiplication of modes of material (self-)production through its process of othering. Thus, the world swells up from the inside and expands on both the material and the semantic level, producing a multiplicity of fractal microcosms. Issues of responsibility and justice arise that are intricately linked to the materiality of the world and take place in and between the various bodies and spaces of the world but without an overarching hierarchy or principle. This approach is a way of counteracting the all-pervasive Hegelian understanding of synthesis, arguing instead for a plenitude that brims with positivity and that can never become fully complete. The world remains its own infinite process of worlding.