Design of a power-aware digital image rejection receiver

This paper deals with and details the design of a power-aware adaptive digital image rejection receiver based on blind-source-separation that alleviates the RF analog front-end impairments. Power-aware system design at the RTL level without having to redesign arithmetic circuits is used to reduce the power consumption in nomadic devices. Power-aware multipliers with configurable precision are used to trade-off the image-rejection-ratio (IRR) performance with power consumption. Results of the simulation case studies demonstrate that the IRR performance of the power-aware system is comparable to that of the normal implementation albeit degraded slightly, but well within the acceptable limits.

Adaptive compensation of analog front-end I/Q mismatches in digital receivers

I and Q Channel phase and gain misniatches are of great concern in communications receiver design. In this paper we analyse the effects of I and Q channel mismatches and propose a low-complexity blind adaptive algorithm to minimize this problem. The proposed solution consists of two, 2-tap adaptive filters, arranged in Adaptive Noise Canceller (ANC) set-up, with the output of one cross-fed to the input of the other. The system works as a de-correlator eliminating I and Q mismatch errors.

Theorising and analysing digital labour: from global value chains to modes of production

This paper considers the following question—where do computers, laptops and mobile phones come from and who produced them? Specific cases of digital labour are examined—the extraction of minerals in African mines under slave-like conditions; ICT manufacturing and assemblage in China (Foxconn); software engineering in India; call centre service work; software engineering at Google within Silicon Valley; and the digital labour of internet prosumers/users. Empirical data and empirical studies concerning these cases are systematically analysed and theoretically interpreted. The theoretical interpretations are grounded in Marxist political economy. The term ‘global value chain’ is criticised in favour of a complex and multidimensional understanding of Marx’s ‘mode of production’ for the purposes of conceptualizing digital labour. This kind of labour is transnational and involves various modes of production, relations of production and organisational forms (in the context of the productive forces). There is a complex global division of digital labour that connects and articulates various forms of productive forces, exploitation, modes of production, and variations within the dominant capitalist mode of production.

Against divisiveness: Digital workers of the world unite! A rejoinder to César Bolaño and Eloy Vieira

This piece is a short rejoinder to César Bolaño’s paper The Political Economy of the Internet and related articles (e.g., Comor, Foley, Huws, Reveley, Rigi and Prey, Robinson) that center around the relevance of Marx’s labor theory of value for understanding social media. I argue that Dallas Smythe’s assessment of advertising was made to distinguish his approach from the one by Baran and Sweezy. Smythe developed the idea of capital’s exploitation of the audience at a time when both feminist and anti-imperialist Marxists challenged the orthodox idea that only white factory workers are exploited. The crucial question is how to conceptualize productive labor. This is a theoretical, normative, and political question. A mathematical example shows the importance of the “crowdsourcing” of value-production on Facebook. I also point out parallels of the contemporary debate to the Soviet question of who is a productive or unproductive worker in the Material Product System.

Georg Lukács as a Communications Scholar: Cultural and Digital Labour in the Context of Lukács’ Ontology of Social Being

The task of this work is to apply thoughts from Georg Lukács’ final book, the Ontology of Social Being, for the theoretical analysis of cultural and digital labour. It discusses Lukács’ concepts of work and communication and relates them to the analysis of cultural and digital work. It also analyses his conception of the relation of labour and ideology and points out how we can make use of it for critically understanding social media ideologies. Lukács opposes the dualist separation of the realms of work and ideas. He introduces in this context the notion of teleological positing that allows us to better understand cultural and digital labour as well as associated ideologies, such as the engaging/connecting/sharing-ideology, today. The analysis shows that Lukács’ Ontology is in the age of Facebook, YouTube, and Twitter still a very relevant book, although it has thus far not received the attention that it deserves. This article also introduces the Ontology’s main ideas on work and culture, which is important because large parts of the book have not been translated from the German original into English. Lukács’ notion of teleological positing is crucial for understanding the common features of the economy and culture.

Alienation and Digital Labour – a Depth-Hermeneutic Inquiry into Online Commodification and the Unconscious

At the core of this paper is a psychosocial inquiry into the Marxist concept of alienation and its applications to the field of digital labour. Following a brief review of different theoretical works on alienation, it looks into its recent conceptualisations and applications to the study of online social networking sites. Finally, the authors offer suggestions on how to extend and render more complex these recent approaches through in-depth analyses of Facebook posts that exemplify how alienation is experienced, articulated, and expressed online. For this perspective, the article draws on Rahel Jaeggi’s (2005) reassessment of alienation, as well as the depth-hermeneutic method of “scenic understanding” developed by Alfred Lorenzer (e.g. 1970; 1986).

Cyborg Subjects: Discourses on Digital Culture

This book is an interrogation of humanity's new potentials and threats brought by technology when the question of social change is becoming more crucial than ever. Collected in the course of 2010-2012, the selected essays in this anthology confront questions from a wide-ranging perspective that evoke the postmodern idea of the cyborg to illuminate recent phenomena from global warming, Wikileaks, to the Occupy movements. Multiple disciplines from music to psychoanalysis to journalism to anthropology collaborate to examine the way we shape the world from behind our ubiquitous screens to taking to the streets in mass protests. What does the increasing omnipotence of networked machines ultimately mean? What do social networks do to our sense of self, others and society? Does P2P technology foster new ethics and spiritualities? What potentials does posthumanity have to bring about social change? Featuring essays from Robert Barry, Siri Driessen & Roos van Haaften, Bonni Rambatan, Dustin Cohen, Jacob Johanssen, Michel Bauwens, Aliki Tzatha, Zakary Paget, Stefen Baack, Alessandro Zagato, Peter Nikolaus Funke, Glenn Muschert, and Jung-Hua Liu.

An FPGA based decimation filter processor design for real-time continuous-time Σ−Δ modulator performance measurement and evaluation

This paper reports on a Field Programmable Gate Array (FPGA) implementation as well as prototyping for real-time testing of a low complexity high efficiency decimation filter processor which is deployed in conjunction with a custom built low-power jitter insensitive Continuous Time (CT) Sigma-Delta (Σ-Δ) Modulator to measure and assess its performance. The CT Σ-Δ modulator/decimation filter cascade can be used in integrated all-digital microphone interfaces for a variety of applications including mobile phone handsets, wireless handsets as well as other applications requiring all-digital microphones. The work reported here concentrates on the design and implementation as well as prototyping on a Xilinx Spartan 3 FPGA development system and real-time testing of the decimation processing part deploying All-Pass based structures to process the bit stream coming from CT Σ-Δ modulator hence measuring in real-time and fully assessing the modulator's performance.

NFC RF Analog Challenge and Enhanced High Speed Transmitter Design

This paper investigates the inherent radio frequency analog challenges associated with near field communication systems. Furthermore, the paper presents a digital based sigma-delta modulator for near field communication transmitter implementations. The proposed digital transmitter architecture is designed to best support data intensive applications requiring higher data rates and complex modulation schemes. An NFC transmitter based on a single-bit sigma-delta DAC is introduced, and then the multi-bit extension with necessary simulation results are presented to confirm the suitability of the architecture for near field communication high speed applications.

Gold, power, protest: Digital and social media and protests against large-scale mining projects in Colombia

Colombia’s Internet connectivity has increased immensely. Colombia has also ‘opened for business’, leading to an influx of extractive projects to which social movements object heavily. Studies on the role of digital media in political mobilisation in developing countries are still scarce. Using surveys, interviews, and reviews of literature, policy papers, website and social media content, this study examines the role of digital and social media in social movement organisations and asks how increased digital connectivity can help spread knowledge and mobilise mining protests. Results show that the use of new media in Colombia is hindered by socioeconomic constraints, fear of oppression, the constraints of keyboard activism and strong hierarchical power structures within social movements. Hence, effects on political mobilisation are still limited. Social media do not spontaneously produce non-hierarchical knowledge structures. Attention to both internal and external knowledge sharing is therefore conditional to optimising digital and social media use.