Radio Physical Layer RADIO ACCESS LAYERS
12.3 RADIO ACCESS LAYERS
A high-speed but low-complexity wireless access technique is critical for providing QoS-based multimedia services to portable terminals. This section outlines wireless-specific protocol layers. These include a radio physical Ž . Ž . layer, a medium access control MAC layer, and a data link control DLC layer. 112.3.1 Radio Physical Layer
WATM requires a high-speed radio technology capable of providing reason- ably reliable transmission and reception in the range of 100᎐500 m. WATM systems may operate in various frequency bands depending on the regulatory policies. Currently, they are usually associated with the recently allocated w x 5 GHz band in the US and the HIPERLAN 22 band in Europe. The expected operating frequency range is on the order of 20᎐25 GHz. Typical target bit rates for the radio physical layer of WATM are around 25 Mbitrs, and a modem must be able to support burst operation with relatively short preambles consistent with transmission of short control packets and ATM cells. The radio physical layer can be divided into the radio physical medium Ž . Ž . dependent RPMD and the radio transmission convergence RTC sub-layers w x 25 . The RPMD sublayer specifies the lower-level transmission require- ments, while the RTC sublayer specifies details of formatted data transmis- sion. w x In 12 , the RTC sublayer adopts a dynamic TDMArTDD approach where several virtual circuits are multiplexed in a single radio channel. The TDMArTDD frame structure is shown in Figure 12.3. Ž . The frame consists of 480 slots every 1.5 ms 25.6 Mbitrs . Each slot is formed by 10 bytes, including 8 data bytes and a 2-byte Reed᎐Solomon code w Ž .x Ž . RS 10, 8 for FEC. The frame is divided into an uplink mobile to base and Ž . a downlink base to mobile part. The downlink subframe consists of the 1 w x In 22 the radio access layers consist of a radio physical layer and a radio DLC layer that Ž . contains a MAC sublayer and a logical link control LLC sublayer. RADIO ACCESS LAYERS 345 Fig. 12.3 Dynamic TDMArTDD frame structure. Ž . Ž . modem preamble P , the subframe delineation overhead O , and the Ž . control region C , followed by WATM cells. The preamble is required for TDMA frame delineation and modem synchronization. The frame header in Ž . the downlink subframe delineation overhead O consists of a frame number, Ž . a radio port identifier, and reser®ed bytes. The number of control packets C Ž . delineates the control region. Control packets 8-byte are embedded in the TDMArTDD slots. They are used by the MAC and DLC layers. WATM Ž . cells 56-byte transport multiplexed downlink user information. The base station controls the uplink bandwidth allocation for WATM cells from each mobile, taking into account the number and type of active WIRELESS ATM SWITCHES 346 connections and their bandwidth requirements. Mobiles assemble a subframe similar to that of the base station. The slotted ALOHA region is used by the mobile terminals to send their bandwidth requirements to the base station.12.3.2 Medium Access Control Layer
Parts
» ATM Switch Structure ATM SWITCH SYSTEMS
» DESIGN CRITERIA AND PERFORMANCE REQUIREMENTS
» Internal Link Blocking Output Port Contention Head-of-Line Blocking
» Shared-Medium Switch Time-Division Switching
» Single-Path Switches Space-Division Switching
» Multiple-Path Switches Space-Division Switching
» Internally Buffered Switches Recirculation Buffered Switches
» Input- and Output-Buffered Switches Virtual-Output-Queueing Switches
» Input-Buffered Switches PERFORMANCE OF BASIC SWITCHES
» Output-Buffered Switches PERFORMANCE OF BASIC SWITCHES
» Completely Shared-Buffer Switches PERFORMANCE OF BASIC SWITCHES
» Bernoulli Arrival Process and Random Traffic On–Off Model and Bursty Traffic
» Multiline Input Smoothing Speedup Parallel Switch
» Window-Based Lookahead Selection Increasing Scheduling Efficiency
» VOQ-Based Matching Increasing Scheduling Efficiency
» Parallel Iterative Matching PIM Iterative Round-Robin Matching iRRM
» Iterative Round-Robin with SLIP i SLIP
» Dual Round-Robin Matching DRRM
» Round-Robin Greedy Scheduling SCHEDULING ALGORITHMS
» Bidirectional Arbiter Design of Round-Robin Arbiters r
» Token Tunneling This section introduces a more efficient arbi-
» Most-Urgent-Cell-First Algorithm MUCFA OUTPUT-QUEUING EMULATION
» Critical Cell First CCF Last In, Highest Priority LIHP
» LOWEST-OUTPUT-OCCUPANCY-CELL-FIRST JONATHAN CHAO CHEUK LAM
» LINKED LIST APPROACH JONATHAN CHAO CHEUK LAM
» CONTENT-ADDRESSABLE MEMORY APPROACH JONATHAN CHAO CHEUK LAM
» Washington University Gigabit Switch
» Shared-Memory Switch with a Multicast Logical Queue Shared-Memory Switch with Cell Copy
» Shared-Memory Switch with Address Copy
» BANYAN NETWORKS JONATHAN CHAO CHEUK LAM
» Three-Phase Implementation Ring Reservation
» BATCHER-SORTING NETWORK THE SUNSHINE SWITCH
» Tandem Banyan Switch DEFLECTION ROUTING
» Shuffle-Exchange Network with Deflection Routing
» Dual Shuffle-Exchange Network with Error-Correcting Routing
» Generalized Self-Routing Algorithm Broadcast Banyan Network
» Boolean Interval Splitting Algorithm Nonblocking Condition of Broadcast Banyan Networks A
» Encoding Process MULTICAST COPY NETWORKS
» Concentration Decoding Process Overflow and Call Splitting
» A. Cyclic Running Adder Network Figure 5.34 shows the struc-
» Concentration The starting point in a CRAN may not be port 0,
» Basic Architecture SINGLE-STAGE KNOCKOUT SWITCH
» Knockout Concentration Principle SINGLE-STAGE KNOCKOUT SWITCH
» Construction of the Concentrator
» Maximum Throughput CHANNEL GROUPING PRINCIPLE
» Two-Stage Configuration A TWO-STAGE MULTICAST OUTPUT-BUFFERED ATM SWITCH
» Multicast Grouping Network A TWO-STAGE MULTICAST OUTPUT-BUFFERED ATM SWITCH
» Translation Tables A TWO-STAGE MULTICAST OUTPUT-BUFFERED ATM SWITCH
» Cross-Stuck CS Fault Toggle-Stuck TS Fault Verticalr
» Toggle-Stuck and Cross-Stuck Cases
» Vertical-Stuck and Horizontal-Stuck Cases
» Cross-Stuck and Toggle-Stuck Cases
» Vertical-Stuck Case Horizontal-Stuck SWE Case
» APPENDIX JONATHAN CHAO CHEUK LAM
» BASIC ARCHITECTURE JONATHAN CHAO CHEUK LAM
» MULTICAST CONTENTION RESOLUTION ALGORITHM
» IMPLEMENTATION OF INPUT PORT CONTROLLER
» Cell Loss Probability PERFORMANCE
» ATM ROUTING AND CONCENTRATION CHIP
» Memoryless Multistage Concentration Network
» Buffered Multistage Concentration Network
» Resequencing Cells ENHANCED ABACUS SWITCH
» Complexity Comparison ENHANCED ABACUS SWITCH
» Packet Interleaving ABACUS SWITCH FOR PACKET SWITCHING
» Cell Interleaving ABACUS SWITCH FOR PACKET SWITCHING
» MSDA Structure MULTIPLE-QOS SDA SWITCH
» OVERVIEW OF CROSSPOINT-BUFFERED SWITCHES OVERVIEW OF INPUT
» Basic Architecture Unicasting Operation
» ROUTING PROPERTIES AND SCHEDULING METHODS
» A SUBOPTIMAL STRAIGHT MATCHING METHOD
» Basic Architecture Distributed and Random Arbitration
» Basic Architecture THE CONTINUOUS ROUND-ROBIN DISPATCHING SWITCH
» Concurrent Round-Robin Dispatching Scheme
» Homogeneous Capacity and Route Assignment
» The Staggering Switch ALL-OPTICAL PACKET SWITCHES
» HYPASS OPTOELECTRONIC PACKET SWITCHES
» STAR-TRACK OPTOELECTRONIC PACKET SWITCHES
» Cisneros and Brackett’s Architecture
» Basic Architecture THE 3M SWITCH
» Cell Delineation Unit THE 3M SWITCH
» VCI-Overwrite Unit Cell Synchronization Unit
» Input and Output Forwarding Engines Input and Output Switch Interfaces
» Route Controller Router Module and Route Controller
» Input Optical Module Output Optical Module Tunable Filters
» Principles of Ping-Pong Arbitration Consider an N-input
» Performance of PPA Implementation of PPA
» Priority PPA Ping-Pong Arbitration Unit
» Component Complexity OIN Complexity
» Power Budget Analysis OPTICAL INTERCONNECTION NETWORK FOR
» Crosstalk Analysis OPTICAL INTERCONNECTION NETWORK FOR
» System Considerations WIRELESS ATM STRUCTURE OVERVIEWS
» NEC’s WATMnet Prototype System
» Olivetti’s Radio ATM LAN Virtual Connection Tree
» BAHAMA Wireless ATM LAN NTT’s Wireless ATM Access
» Radio Physical Layer RADIO ACCESS LAYERS
» Medium Access Control Layer Data Link Control Layer
» Connection Rerouting HANDOFF IN WIRELESS ATM
» Buffering Cell Routing in a COS
» Design of a Mobility-Support Switch
» Performance MOBILITY-SUPPORT ATM SWITCH
» Architectures of Generic Routers
» IP ROUTE LOOKUP BASED ON CACHING TECHNIQUE IP ROUTE LOOKUP BASED ON STANDARD
» Levels 2 and 3 of Data Structure
» Adapting Binary Search for Best-Matching Prefix
» Precomputed 16-Bit Prefix Table Multiway Binary Search: Exploiting the Cache Line
» Lookup Algorithms and Data Structure Construction
» Prefix Update Algorithms IP ROUTE LOOKUPS USING TWO-TRIE STRUCTURE
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