Turbo channel estimation and equalisation for a superposition-based cooperative system

This study investigates the superposition-based cooperative transmission system. In this system, a key point is for the relay node to detect data transmitted from the source node. This issued was less considered in the existing literature as the channel is usually assumed to be flat fading and a priori known. In practice, however, the channel is not only a priori unknown but subject to frequency selective fading. Channel estimation is thus necessary. Of particular interest is the channel estimation at the relay node which imposes extra requirement for the system resources. The authors propose a novel turbo least-square channel estimator by exploring the superposition structure of the transmission data. The proposed channel estimator not only requires no pilot symbols but also has significantly better performance than the classic approach. The soft-in-soft-out minimum mean square error (MMSE) equaliser is also re-derived to match the superimposed data structure. Finally computer simulation results are shown to verify the proposed algorithm.

Affective disruption: Walter Benjamin and the 'history' of Ireland's industrial schools

What role do organizations play in writing history? In this paper, I address the part played by organizations in the enactment of large-scale violence, and focus on the ways in which the resulting histories come to be written. Drawing on the case of Ireland's industrial schools, I demonstrate how such accounts can act to serve the interests of those in power, effectively silencing and marginalizing weaker people. A theoretical lens that draws on ideas from Walter Benjamin and Judith Butler is helpful in understanding this; the concept of 'affective disruption' enables an exploration of how people's experiences of organizational violence can be reclaimed from the past, and protected in a continuous remembrance. Overall, this paper contributes a new perspective on the writing of organizational histories, particularly in relation to the enactment of violence.