As a noun functional In High-MAC sublayer the centralized scheduling in the High-MAC sublayer will be in charge of the control of multiple Low-MAC sublayers. It reduces the delay requirements on the fronthaul interface. What is Inter Symbol Interference (ISI) in LTE, How Cyclic Prefix (CP) helps eliminating this problem ? This allows efficient support of functions such as CoMP, MIMO, load balancing, mobility. Individual items identified in logical architecture may reside on common devices, physically. Logical Decomposition Purpose The Logical Decomposition Process is used to: Improve understanding of the defined technical requirements and the relationships among the requirements (e.g. 3GPP TR 38.801 Radio Access Architecture and Interfaces Release 14. This split permit centralization of processes at all protocol layer levels, resulting in very tight coordination of the RAN. This option requires some kind of compression technique to reduce transport bandwidth requirements between the DU and CU. Option 2-1 Split U-plane only (3C like split): In this split option, RRC, PDCP are in the central unit. It defines how the functions will operate together to perform the system mission(s). view, a behavioral architecture. The logical architecture of gNB is shown in figure below with Central Unit (CU) and Distributed Unit (DU). A functional software architecture (FSA) is an architectural model that identifies enterprise functions, interactions and corresponding IT needs. is that functional is (computing) an object encapsulating a function pointer (or equivalent) while logical is (computing) non-physical or conceptual yet underpinned by something physical or actual. The functional view de nes the functions that a user can invoke at the boundary of the system. This means that these different … Its operation is controlled by the CU. and measurements. Thus the entire user plane is in the distributed unit. RLC, MAC, physical layer and RF are in the distributed unit. CA, eICIC, CoMP etc. HARQ) or the functions where performance is proportional to latency (e.g. Low RLC may be composed of segmentation functions; High RLC may be composed of ARQ and other RLC functions; Low RLC may be composed of transmitting TM RLC entity, transmitting UM RLC entity, a transmitting side of AM and the routing function of a receiving side of AM, which are related to downlink transmission. Logical versus physical architecture. It includes a functional architecture, a behavioral architecture, and a temporal architecture [2]. Option 3 (High RLC/Low RLC Split): In this option, two approaches are taken based on Real time/Non-Real time functions split which are as follows: This option splits the RLC sublayer into High RLC and Low RLC sublayers such that for RLC Acknowledge Mode operation, all RLC functions may be performed at the High RLC sublayer residing in the central unit, while the segmentation may be performed at the Low RLC sublayer residing in the distributed unit. Functional Decomposition • Functional decomposition is a cornerstone of systems engineering processes. Some examples of such factors are: (adsbygoogle = window.adsbygoogle || []).push({}); Licensed Wi-Fi 802.11(l) : Architecture and Role in 5G, Wi-Fi Now Event is now much closer to India this November, Pixel Story of Video Broadcasting By Neha Shah with Urvashi Pal, Beacons Technology – What it is, How it works and Its Applications and Challenges. High RLC may be composed of receiving TM RLC entity, receiving UM RLC entity and a receiving side of AM except for the routing function and reception of RLC status reports, which are related to uplink transmission. RLC, MAC, physical layer and RF are in the distributed unit. Option 5 assumes the following distribution: Therefore, by splitting the MAC layer into 2 entities (e.g. As adjectives the difference between functional and logical is that functional is in good working order while logical is (not comparable) in agreement with the principles of logic. For the initial phase, 3GPP has taken LTE protocol stack as a basis for the discussion, until RAN2 defines and freezes the protocol stack for New Radio (NR). Process, Functional Architecture, Logical Architecture, Technical Architecture, Model-Driven Architecture, Adaptive Cruise Control 1 Introduction Motivation. As a part of study item for New Radio (NR), 3GPP started studying different functional splits between central and distributed units. Central Unit (CU): It is a logical node that includes the gNB functions like Transfer of user data, Mobility control, Radio access network sharing, Positioning, Session Management etc., except those functions allocated exclusively to the DU. Features requirement at Radio Network level e.g. For example, a diagram that illustrates the relationship between software components. What exactly is the difference between the logical and the physical design?There are a plethora of logical and physical architecture diagrams throughout the IT world, so many in fact that we expect to find them in our literature. Option 7 (Intra PHY split): Multiple realizations of this option are possible, including asymmetrical options which allow obtaining benefits of different sub-options for UL and DL independently. They have proposed about 8 possible options shown in below figure. Logical architecture is a structural design that gives as much detail as possible without constraining the architecture to a particular technology or environment. Functional architecture is described as “an architectural model that identifies system function and their interactions. Considering above there are three sub-variant available for this option described as below. It takes high-level centralized scheduling decision. To further the confusion, the word "Architecture" tends to be associated with either “Requirements” or “Logical” whereas "Design" tends to be associated with “Physical.” This probably stems from the fact that we, the I/S community, are starting at Row 3 and in an absolute, Enterprise sense, don’t … High-MAC and Low-MAC), the services and functions provided by the MAC layer will be located in the Central Unit (CU), in the Distributed Unit (DU), or in both. In fact it allows architects to model things both at a high and low levels, depending on the requirements, which makes it very important for the architecture process. Option 4 (RLC-MAC split): In this split option, RRC, PDCP, and RLC are in the central unit. From an abstraction level viewpoint, it represents a middle ground, sitting between the Conceptual and Physical architectures. These functions can be used as a reference by different domain experts to develop IT-systems as part of a co-operative information-driven enterprise. In the downlink, iFFT and CP addition reside in the DU and the rest of the PHY resides in the CU. • SysML activity diagrams can be used to fulfill this role and have the added advantage of being easily allocated to logical architectural variants. In the DL, iFFT and CP addition functions reside in the DU, the rest of PHY functions reside in the CU. The logical view de nes the internal implementation of the system as a hierarchy of components. The inter-cell interference coordination in the High-MAC sublayer will be in charge of interference coordination methods such as JP/CS CoMP. MAC, physical layer, and RF are in the distributed unit. In Low-MAC sublayer the time-critical functions in the Low-MAC sublayer include the functions with stringent delay requirements (e.g. Fs-C and Fs-U provide control plane and user plane connectivity over Fs interface. It can also measure/estimate the activities on the configured operations or the served UE’s statistics and report periodically or as requested to the High-MAC sublayer. C-plane since some new procedures may be needed. • Many methods have been used, including functional-flow block diagrams (FFBDs) and IDEF0. Really, the only limitations are the performance and capabilities of the physical device.