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This paper examines the Longquan celadon industry, located in Zhejiang province in China, which flourished mainly between the Southern Song and early Ming dynasties (12th to 15th century). The products of this industry are found on archaeological sites from across China and the Indian Ocean. This paper attempts a quantified analysis of the development of the industry based on archaeological data, focussing on four aspects: production, domestic consumption, overseas consumption and, to a lesser degree, workshop organisation. Although much of the data is still, in many ways, problematic, and many of the conclusions drawn are necessarily tentative, it is possible to demonstrate the value and timeliness of the approach by charting the overall development of this industry and by arguing that the close integration of the four aspects examined indicates that the Longquan celadon industry was an industry of considerable economic significance across much of the Indian Ocean.

In 2012 a group of researchers proposed a basic research initiative to the German Research Foundation (DFG) as a special priority project (SPP) with the name: Wireless 100 Gbps and beyond. The main goal of this initiative was the investigation of architectures, technologies and methods to go well beyond the state of the art. The target of 100 Gbps was set far away from the (at that time) achievable 1 Gbps such that it was not possible to achieve promising results just by tuning some parameters. We wanted to find breakthrough solutions. When we started the work on the proposal we discussed the challenges to be addressed in order to advancing the wireless communication speed significantly. Having the fundamental Shannon boundary in mind we discussed how to achieve the 100 Gbps speed., Angesichts der rapiden Entwicklung der Funkkommunikation hat die Deutsche Forschungsgemeinschaft im Jahr 2012 ein Schwerpunktprogramm mit dem Titel "Wireless 100 Gbps and beyound" (dt.: Drahtloskommunikation mit 100 Gbps und mehr) gestartet. Diese Initiative zielte auf neue Lösungen, Methoden und neues Wissen zur Lösung des Problems des kontinuierlichen Bedarfs an immer höheren Datenraten im Bereich der Funkkommunikation. Eine international besetze Jury hat etliche Projektvorschläge evaluiert, aus denen 11 Projekte ausgewählt und über zweimal 3 Jahre von Mitte 2013 bis Mitte 2019 gefördert wurden. Das vorliegende Buch versammelt die Ansätze, Architekturen und Erkenntnisse der Projekte. Es überspannt einen breiten Themenbereich, angefangen mit speziellen Fragen der physikalischen Übertragung, des Antennendesigns und der HF-Eingangs-Architekturen für unterschiedliche Frequenzbereiche bis 240 GHz. Darüber hinaus beschreibt das Buch Ansätze für Ultra-Hochgeschwindigkeits-Funksysteme, deren Basisbandverarbeitung, Kodierung sowie mögliche Umsetzungen. Nicht zuletzt wurden auch Fragen des Protokolldesigns behandelt, um eine enge Integration in moderne Computersysteme zu erleichtern.

Fixed wireless communication is a cost-efficient solution for flexible and rapid front-/backhaul deployments. Technologies including dual polarization, carrier aggregation, and higher order modulation schemes have been developed for enhancing its throughput. In order to better support the massive traffic increment during network evolution, novel wireless backhaul solutions with possible new dimensions in increasing the spectral efficiency are needed. Line-of-Sight (LoS) Multiple-Input-Multiple-Output (MIMO) communication is such a promising candidate allowing the throughput to scale linearly with the deployed antenna pairs. Spatial multiplexing with sub-channels having approximately equal quality exists within a single LoS direction. In addition, operating at millimeter wave (mmWave) frequencies or higher, the abundantly available bandwidth can further enhance the throughput of LoS MIMO communication. The mmWave LoS MIMO communication in this work exploits the spatial multiplexing from the structured phase couplings of a single path direction, while most of the state-of-the-art works in mmWave communication focus on the spatial multiplexing from the spatial signature of multiple path directions. Challenges: The performance of a LoS MIMO system is highly dependent on the antenna topology. Topologies resulting in theoretically orthogonal channels are considered as optimal arrangements. The general topology solution from a unified viewpoint is unknown. The known optimal arrangements in the literature are rather independently derived and contain restrictions on their array planes. Moreover, operating at mmWave frequencies with wideband signals introduces additional challenges. On one hand, high pathloss is one limiting factor of the received signal power. On the other hand, high symbol rates and relatively high antenna numbers create challenges in signal processing, especially the required complexity for compensating hardware imperfections and applying beamforming. Targets: In this thesis, we focus on antenna topologies and signal processing schemes to effectively handle the complexity challenge in LoS MIMO communications. Considering the antenna topology, we target a general solution of optimal arrangements on any arbitrarily curved surface. Moreover, we study the antenna topologies with which the system gains more streams and better received signals. Considering the signal processing, we look for low complexity schemes that can effectively compensate the hardware impairments and can cope with a large number of antennas. Main Contributions: The following models and algorithms are developed for understanding mmWave LoS spatial multiplexing and turning it into practice. First, after analyzing the relation between the phase couplings and the antenna positions in three dimensional space, we derive a channel factorization model for LoS MIMO communication. Based on this, we provide a general topology solution from a projection point of view and show that the resulting spatial multiplexing is robust against moderate displacement errors. In addition, we propose a multi-subarray LoS MIMO system for jointly harvesting the spatial multiplexing and array gains. Then, we propose a novel algorithm for LoS MIMO channel equalization, which is carried out in the reverse order w.r.t. the channel factorization model. The number of multiplications in both digital and analog implementations of the proposed solution is found to increase approximately linearly w.r.t. the number of antennas. The proposed algorithm thus potentially reduces complexity for equalizing the channel during the system expansion with more streams. After this, we focus on algorithms that can effectively estimate and compensate the hardware impairments. A systolic/pipelined processing architecture is proposed in this work to achieve a balance between computational complexity and performance. The proposed architecture is a viable approach that scales well with the number of MIMO streams. With the recorded data from a hardware-in-the-loop demonstrator, it is shown that the proposed algorithms can provide reliable signal estimates at a relatively low complexity level. Finally, a channel model is derived for mmWave systems with multiple widely spaced subarrays and multiple paths. The spatial multiplexing gain from the spatial signature of multiple path directions and the spatial multiplexing gain from the structured phase couplings of a single path direction are found simultaneously at two different levels of the antenna arrangements. Attempting to exploit them jointly, we propose to use an advanced hybrid analog/digital beamforming architecture to efficiently process the signals at reasonable costs and complexity. The proposed system can overcome the low rank property caused by the limited number of propagation paths.