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The paper and board industry (PBI) faces a series of challenges, ranging from shifts in the availability and quality of raw materials to the generation of large amounts of sidestreams whose disposal entails significant costs. The concept of the “Multiple Input-Multiple Output (MIMO) Paper Mill” is proposed here as an option for addressing these issues by introducing, on the one hand, flexibility regarding the types of fibre sources that can be used as raw materials and, on the other, a full utilisation of all fractions of the raw materials, including those that were so far considered to be sidestreams of papermaking. With regard to raw material flexibility, researchers have implemented various pretreatment and pulping methods on potential alternative, non-wood, fibre sources for the PBI, which can be found primarily in agro-industrial residues and plants specially cultivated for this purpose. Research on the conversion of various types of papermaking sidestreams into energy and material products has also been extensive, with the new products aimed at (re)use within both the PBI itself and other sectors. Given that technical aspects have gained the most attention so far, more focus should now be placed also on the economic and organisational sides of the concept. It is also crucial to start evaluating integrated MIMO cases, taking into account the interconnected effects that new raw materials have on the papermaking process and its sidestreams, instead of looking into isolated MI and MO examples. [ABSTRACT FROM AUTHOR]

Recent research has shown that frequency domain pre-equalization (FDPE) can provide broadcast transmissions over multi-input multi-output (MIMO) frequency selective channels, where the multiple receivers need limited processing. In this paper, we consider the combination of FDPE with parallel and successive Tomlinson-Harashima Precoding (THP) and propose two novel FDPE MIMO schemes, which are referred to as FDPE-P-THP and FDPE-S-THP, respectively, based on the minimum mean square error (MMSE) criterion. The ordering algorithm in the FDPE-S-THP scheme is considered and it is shown that the system with even a randomly selected order can perform almost as well as that with the optimal one. This paper further develops an accurate theoretical performance analysis methodology for the proposed FDPE-THP schemes. Numerical results along with analytical results demonstrate the significant performance improvement of our proposed schemes compared to the conventional FDPE MIMO schemes. The channel estimation errors and channel variation effects on the proposed system are also investigated. It is shown that the performance degradation due to channel variation can be efficiently reduced by applying channel prediction. [ABSTRACT FROM AUTHOR]

This paper is concerned with the low-cost iterative equalization/detection principles for coded linear systems with cyclic prefixes. Turbo frequency-domain-equalization (FDE) is applied to systems that may contain the joint effect of multiple-access interference (MAI), cross-antenna interference (CAI) and inter-symbol interference (ISI). We develop an SNR-variance evolution technique for the performance evaluation of the proposed systems. Numerical results in various channel environments demonstrate excellent agreement between the predicted and simulated system performance. [ABSTRACT FROM AUTHOR]

This paper describes a silicon receiver for a multiple-input multiple-output (MIMO) wireless channel that supports up to 28.8 Mb/s using a 4 × 4 QPSK configuration over a 5-MHz frequency selective channel. The architecture has two key components: a space-time equalizer that mitigates both spatial and temporal effects of the channel, and a maximum likelihood detector with approximate a posterior probability (ML-APP) soft estimates of the transmit vectors over the MIMO configuration. The space-time equalizer uses an adaptive tap training process that includes a pilot correlator to reduce adaptation noise. The device is 685 k effective logic gates (11.6 mm²) in 0.18-pm 6LM CMOS. [ABSTRACT FROM AUTHOR]