Complex field coded MIMO systems: performance, rate, and trade-offs

2002 ◽  
Vol 2 (7) ◽  
pp. 693-717 ◽  
Author(s):  
Xiaoli Ma ◽  
Georgios B. Giannakis
Keyword(s):  
Mimo Systems ◽  
Complex Field ◽  
Trade Offs ◽  
Performance Rate

scholarly journals Design Trade-offs for Decentralized Baseband Processing in Massive MU-MIMO Systems

2019 ◽  
Author(s):  
Kaipeng Li ◽  
James McNaney ◽  
Chance Tarver ◽  
Oscar Castaneda ◽  
Charles Jeon ◽  
...  
Keyword(s):  
Mimo Systems ◽  
Trade Offs ◽  
Baseband Processing

scholarly journals Low Complexity Hybrid Precoding Designs for Multiuser mmWave/THz Ultra Massive MIMO Systems

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6054
Author(s):  
João Pedro Pavia ◽  
Vasco Velez ◽  
Renato Ferreira ◽  
Nuno Souto ◽  
Marco Ribeiro ◽  
...  
Keyword(s):  
Antenna Arrays ◽  
Massive Mimo ◽  
Communication Systems ◽  
High Speed ◽  
Mimo Systems ◽  
Low Complexity ◽  
Phase Shifters ◽  
High Signal ◽  
Design Algorithm ◽  
Trade Offs

Millimeter-wave and terahertz technologies have been attracting attention from the wireless research community since they can offer large underutilized bandwidths which can enable the support of ultra-high-speed connections in future wireless communication systems. While the high signal attenuation occurring at these frequencies requires the adoption of very large (or the so-called ultra-massive) antenna arrays, in order to accomplish low complexity and low power consumption, hybrid analog/digital designs must be adopted. In this paper we present a hybrid design algorithm suitable for both mmWave and THz multiuser multiple-input multiple-output (MIMO) systems, which comprises separate computation steps for the digital precoder, analog precoder and multiuser interference mitigation. The design can also incorporate different analog architectures such as phase shifters, switches and inverters, antenna selection and so on. Furthermore, it is also applicable for different structures, namely fully-connected structures, arrays of subarrays (AoSA) and dynamic arrays of subarrays (DAoSA), making it suitable for the support of ultra-massive MIMO (UM-MIMO) in severely hardware constrained THz systems. We will show that, by using the proposed approach, it is possible to achieve good trade-offs between spectral efficiency and simplified implementation, even as the number of users and data streams increases.

TECHNOLOGICAL APPROACH TO SOLVING THE PROBLEM OF MINIMIZING THE INFLUENCE OF DESTABILIZING FACTORS ON THE WORK OF DISTRIBUTED STRUCTURES OF THE GROUND-ROCKOTECHNICAL COMPLEX IN AN INTEGRAL PROJECT «OBJECT-SYSTEM»

2019 ◽  
pp. 5-19
Author(s):  
V. Chepkyi ◽  
V. Skachkov ◽  
O. Yefymchykov ◽  
V. Nabok ◽  
O. Yelchaninov
Keyword(s):  
Control System ◽  
Information Exchange ◽  
Mimo Systems ◽  
Information Control ◽  
Radio Communication ◽  
External Interference ◽  
Object System ◽  
Trade Offs ◽  
Destabilizing Factors ◽  
Distributed Structures

Mobile structures of the ground-based robotic complex (RTC) are investigated as an active component formation of an integrated project “object-system”, which is operated in a destabilizing environment. The relevant problem of minimizing the influence of external destabilizing factors on the operation of mobile spatially-distributed structures of the ground-based RTC is stated in the descriptions of the conceptual apparatus of complex, poorly formalized multicomponent technical systems. Following the logic of this approach, the basic principles of distributed control are determined and their applications are implemented in the mobile structures of the ground-based RTC with elements of subsidiarity. The quintessence of the latter is represented by the technology of multi-antenna MIMO systems, which made it possible to determine the trade-offs of using classical transmission methods and strategies for receiving and processing MIMO signals in the multi-sensory channels of the information-control system (ICS) and radio communication with the data transmission system and commands. Given the complexity of performing the stated tasks, a set of technological functions of reducing the influence of destabilizing factors and their practical variations in the algorithms for obtaining the target result are proposed. A situational model of reducing (minimizing) information losses at the output of the information-control system of the ground-based robotic complex under destabilization has been built. Options have been proposed to achieve the target result: integration of structural and parametric adaptation methods, MIMO technologies, code division multiplexing techniques with CDMA channels, taking into account the heterogeneity factor of information exchange channels and the artificial redundancy of the system itself with respect to the number of external interference sources.

EVALUATION FRAMEWORK FOR K-BEST SPHERE DECODERS

2010 ◽  
Vol 19 (05) ◽  
pp. 975-995 ◽  
Author(s):  
CHUNG-AN SHEN ◽  
AHMED M. ELTAWIL ◽  
KHALED N. SALAMA
Keyword(s):  
Mimo Systems ◽  
Multiple Input Multiple Output ◽  
Evaluation Framework ◽  
Practical Implementation ◽  
Holistic View ◽  
Power Cost ◽  
Sphere Decoder ◽  
Advantages And Disadvantages ◽  
Trade Offs ◽  
Power Delay Product

While Maximum-Likelihood (ML) is the optimum decoding scheme for most communication scenarios, practical implementation difficulties limit its use, especially for Multiple Input Multiple Output (MIMO) systems with a large number of transmit or receive antennas. Tree-searching type decoder structures such as Sphere decoder and K-best decoder present an interesting trade-off between complexity and performance. Many algorithmic developments and VLSI implementations have been reported in literature with widely varying performance to area and power metrics. In this semi-tutorial paper we present a holistic view of different Sphere decoding techniques and K-best decoding techniques, identifying the key algorithmic and implementation trade-offs. We establish a consistent benchmark framework to investigate and compare the delay cost, power cost, and power-delay-product cost incurred by each method. Finally, using the framework, we propose and analyze a novel architecture and compare that to other published approaches. Our goal is to explicitly elucidate the overall advantages and disadvantages of each proposed algorithms in one coherent framework.

Application-aware cross-layer reliability analysis and optimization

2015 ◽  
Vol 57 (3) ◽  
Author(s):  
Michael Glaß ◽  
Hananeh Aliee ◽  
Liang Chen ◽  
Mojtaba Ebrahimi ◽  
Faramarz Khosravi ◽  
...  
Keyword(s):  
Mimo Systems ◽  
Optimization Techniques ◽  
Cross Layer ◽  
Model Errors ◽  
Embedded Control ◽  
Control Applications ◽  
Counter Measures ◽  
Analysis Techniques ◽  
Trade Offs ◽  
Application Aware

AbstractThe increasing error susceptibility of semiconductor devices has put reliability in the focus of modern design methodologies. Low-level techniques alone cannot economically tackle this problem. Instead, counter measures on all system layers from device and circuit up to the application are required. As these counter measures are not for free, orchestrating them across different layers to achieve optimum trade-offs for the application wrt. reliability but also cost, timeliness, or energy consumption becomes a challenge. This typically requires a combination of analysis techniques to quantify the achieved reliability and optimization techniques that search for the best combination of counter measures. This work presents five recent approaches for application-aware cross-layer reliability optimization from within the embedded domain. Moreover, the Resilience Articulation Point (RAP) as a concept cooperatively developed to model errors across different layers is discussed. The developed approaches are showcased via applications, ranging from MIMO systems to distributed embedded control applications.

Novel players fine-tune plant trade-offs

2015 ◽  
Vol 58 ◽  
pp. 83-100 ◽  
Author(s):  
Selena Gimenez-Ibanez ◽  
Marta Boter ◽  
Roberto Solano
Keyword(s):  
Ubiquitin Ligase ◽  
Feedback Loop ◽  
Molecular Level ◽  
26S Proteasome ◽  
Signalling Molecules ◽  
Transcriptional Reprogramming ◽  
Trade Offs ◽  
Jaz Proteins ◽  
Regulatory Feedback Loop ◽  
Fine Tune

Jasmonates (JAs) are essential signalling molecules that co-ordinate the plant response to biotic and abiotic challenges, as well as co-ordinating several developmental processes. Huge progress has been made over the last decade in understanding the components and mechanisms that govern JA perception and signalling. The bioactive form of the hormone, (+)-7-iso-jasmonyl-l-isoleucine (JA-Ile), is perceived by the COI1–JAZ co-receptor complex. JASMONATE ZIM DOMAIN (JAZ) proteins also act as direct repressors of transcriptional activators such as MYC2. In the emerging picture of JA-Ile perception and signalling, COI1 operates as an E3 ubiquitin ligase that upon binding of JA-Ile targets JAZ repressors for degradation by the 26S proteasome, thereby derepressing transcription factors such as MYC2, which in turn activate JA-Ile-dependent transcriptional reprogramming. It is noteworthy that MYCs and different spliced variants of the JAZ proteins are involved in a negative regulatory feedback loop, which suggests a model that rapidly turns the transcriptional JA-Ile responses on and off and thereby avoids a detrimental overactivation of the pathway. This chapter highlights the most recent advances in our understanding of JA-Ile signalling, focusing on the latest repertoire of new targets of JAZ proteins to control different sets of JA-Ile-mediated responses, novel mechanisms of negative regulation of JA-Ile signalling, and hormonal cross-talk at the molecular level that ultimately determines plant adaptability and survival.

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