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WG7051 issue #1 Title: Additional Terms and Definition Source: GSI 은세영 Comment: 3 장에 terms and definitions 가 있기는 하나 SW 에 관련된 용어들만 정의가 되어있는데 문서 초반에 문서에 나오는 모든 약어가 정리가 되어 있으면 어떨가 하는 의견입니다. Resolution 3. Term and Definition 3.1. Definition 1) Beamforming Network (BFN) : BFNs combine signals from small antennas into a pattern that is more directional than each antenna by itself because of array factor. 2) Common Object Request Broker Architecture (CORBA) : An OMG distributed computing platform specification that is independent of implementation languages. 3) Component : A component can always be considered an autonomous unit within a system or subsystem. It has one or more ports, and its internals are hidden and inaccessible other than as provided by its interfaces. A component represents a modular part of a system that encapsulates its contents and whose manifestation is replaceable within its environment. A component exposes a set of ports that define the component specification in terms of provided and required interfaces. As such, a component serves as a type, whose conformance is defined by these provided and required interfaces (encompassing both their static as well as dynamic semantics). 4) Facility : The realization of certain functionality through a set of well defined interfaces. 5) Attributes : A characteristic or feature that someone or something has. 6) Interface Definition Language (IDL) : An OMG and ISO standard language for specifying interfaces and associated data structures. 7) Model : A formal specification of the function, structure and/or behavior of an application or system. 8) Model Driven Architecture (MDA) : An approach to IT system specification that separates the specification of functionality from the specification of the implementation of that functionality on a specific technology platform. 9) Platform : A set of subsystems/technologies that provide a coherent set of functionality through interfaces and specified usage patterns that any subsystem that depends on the platform can use without concern for the details of how the functionality provided by the platform is implemented. 10) Platform Independent Model (PIM) : A model of a subsystem that contains no information specific to the platform, or the technology that is used to realize it. 11) Platform Specific Model (PSM) : A model of a subsystem that includes information about the specific technology that is used in the realization of it on a specific platform, and hence possibly contains elements that are specific to the platform. 12) Unified Modeling Language (UML) : An OMG standard language for specifying the structure and behavior of systems. The standard defines an abstract syntax and a graphical concrete syntax. 13) UML Profile : A standardized set of extensions and constraints that tailors UML to particular use. 14) Extensible Markup Language (XML) : A widely-used computer language for creating and designing pages on the World Wide Web, and for defining other languages with more specialized purposes. 15) Frame Error Rate (FER) : Ratio of data received with errors to total data received. It is used to determine the quality of a signal connection. If the FER is too high (too many errors), the connection may be dropped. 16) Direction of Arrival (DOA) : The direction from which usually a propagating wave arrives at a point, where usually a set of sensors are located. WG7051 issue #2 Title: Description for MU-MIMO/Cooperative MIMO Source: GSI 은세영 Comment: introduction 에 Smart antenna 의 분류 언급되었고 실제 SW architecture 에도 반영이 되어있는데요 최근 LTE 등에서 언급되고 있는 분류 (Single User MIMO, Multi User MIMO, Cooperative MIMO 등)는 의미가 없는지요? Resolution 1.4 Multiple Input Multiple Output (MIMO) In radio, multiple-input and multiple-output (MIMO) is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology. MIMO technology has attracted attention in wireless communications, because it offers significant increases in data throughput and link range without additional bandwidth or transmit power. It achieves this by higher spectral efficiency and link reliability or diversity. MIMO can be sub-divided into two categories, SU-MIMO or MU-MIMO. There are two different types of MIMO schemes: one uses spatial multiplexing to enhance data rate for a given bandwidth (thus, the spectral efficiency) and the other uses space time coding using diversity combining techniques to combat fading. In the multiplexing scheme, data is serial to parallel converted and transmitted simultaneously over multiple antenna elements. The receiver also uses multiple antenna elements to receive the signal and applies a maximum likelihood (ML) algorithm to retrieve the simultaneously transmitted symbols. One key assumption in this case is that the propagation environment has to provide rich scattering; in other words, the propagation channel has to include a large number of scattering objects that will generate independent fading at the antenna elements. In the case of space-time coding, symbols to be transmitted are coded over multiple antennas and symbol time durations in such a way that the receiver can easily regenerate the transmitted signals by doing a linear processing on received signal. The space-time codes rely on the orthogonality present in the coded symbols for proper detection, and additionally they require the fading to be independent between the antenna elements for best performance results. 1.4.1 SU-MIMO Single-user MIMO (SU-MIMO) communication promises large gains for both channel capacity and reliability, essentially via the use of the space-time codes (diversity gain oriented) combined with the spatial multiplexed transmission (rate maximization oriented). In such a single-user view of MIMO systems, the extra spatial degrees of freedom (DoF) brought by the use of multiple antennas are exploited to expand the dimensions available for signal processing and detection, thus acting mainly as a physical (PHY) layer performance booster. In this approach, the link layer protocols for multiple accesses (uplink and downlink) indirectly reap the performance benefits of MIMO antennas in the form of greater per-user rates or more reliable channel quality despite not requiring full awareness of the MIMO capability. 1.4.2 MU-MIMO Multi-user MIMO (MU-MIMO) is a set of advanced MIMO technologies that exploit the availability of multiple independent radio terminals in order to enhance the communication capabilities of each individual terminal. Multi-user MIMO algorithms are developed to enhance MIMO systems when the number of users, or connections, numbers greater than one. The situation with MU- MIMO techniques is radically different as these techniques imply the use of spatial sharing of the channel by the users, thus deeply affecting the design of the multiple access protocol. In spatial multiple access, the resulting multiuser interference is handled by the multiple antennas, which, in addition to providing per-link diversity, also give the DoF necessary for spatial separation of the users. The most substantial cost is due to the fact that MU-MIMO requires channel state information at transmitter (CSIT) to properly serve the spatially multiplexed users. CSIT, while not essential in SU-MIMO communication channels, is of critical importance to most downlink multiuser precoding techniques. The need for CSIT feedback places a significant burden on uplink capacity in most systems, exacerbated in systems with wideband communication or high mobility. 1.4.3 Cooperative MIMO Cooperative MIMO is a technique useful for future cellular networks which consider wireless mesh networking or wireless ad-hoc networking. In wireless ad-hoc networks, multiple transmit nodes communicate with multiple receive nodes. To optimize the capacity of Ad-hoc channels, MIMO concepts and techniques can be applied to multiple links between the transmit and receive node clusters. Contrasted to multiple antennas in a single-user MIMO transceiver, participating nodes and their antennas are located in a distributed manner. So, to achieve the capacity of this network, techniques to manage distributed radio resources are essential. Strategies such as autonomous interference cognition, node cooperation, and network coding with dirty paper coding (DPC) have been suggested as solutions to optimize wireless network capacity. WG7051 issue #3 Title: Additional property for supporting CSI feedback Source: HYU 현승헌 Comment: MU-MIMO, Cooperative MIMO 의 다운링크 빔포밍에 필요한 CSI feedback 을 지원하기 위한 property 들이 요구됨. Resolution 2) Attributes <<ConfigureProperty>>CSIFeedBack: ComplexSeuquece The CSIFeedBack attribute represents the channel state information which is used for adaptive transmission such as transmit beamforming/precoding in MIMO and Beamforming system.
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