A comparison of wi-fi and wimax with case studies - Florida State ...

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subcarriers will be assigned first and then the rest of subcarriers are partitioned into data subchannels. FUSC has one set for pilot subcarriers, but each subchannel in PUSC has its own set for pilot subcarriers. Figure 4-6[53] is the frame structure of OFDMA-TDD. This kind of frame is sliced into DL and UL two subframes. The DL and UL subframes are separated by Transmit/Receive Gap and Receive/Transmit Gap (TRG and RTG).The DL subframe starts with FCH (Frame Control Header) and then a DL-MAP and a UL-MAP. In DL-MAP BS will tell MS which subcarriers are going to assign for it. The UL-MAP includes which subcarriers that MS can use to transmit on. Figure 4-6 OFDMA Frame Structure 4.3.2.1.3. Various Subcarrier Allocation Modes OFDMA supports subchannelization to effectively allocate subchannels for both DL and UL. In WiMax, each user is allocated blocks of subcarriers, not individual subcarriers. This method can decrease the complexity of the subcarrier-allocation algorithm and make the mapping message easier. There are two main types of subcarrier permutations; distributed and adjacent.[50][53] Generally speaking, the distributed subcarrier permutation has very good performance in mobile applications and improves frequency diversity and robustness. Adjacent subcarrier permutation is good at fixed, portable or less mobility surroundings and increases multiuser diversity. DL Distributed Subcarrier Permutations: Fully Used Subchannelization (FUSC) All subchannels and full channel diversity are well utilized in this method by dispensing the allocated subcarriers to subchannels and a permutation mechanism is used here. During 54
transmiission, the aadjacent cellls/sectors mmay hit each other by ceertain possibbility, becauuse of usingg the samme subcarrieers. This meechanism reeuses subcaarriers to minimize thee probabilityy of hits. In n additionn, fast fadinng of mobilee surroundinngs would llower the sy ystem performance. Buut frequencyy diversitty can minimmize it. Tabble 4-5[53] is the summmary of subbcarrier alloocation struucture. In DDL-FUSC th here are twoo kinds of sets of piloot; variable and fixed ssets. The fixxed one is uused in all OOFDM symbbols and thee variablee one is divvided into subsets s useed in odd annd even syymbols alterrnatively. Itt makes thee tradeofff of channell estimationn appropriate between aassigned powwer and freequency diversity. In OOFDMA sppecificationn, the OFDMMA DL andd UL subfraames must bbegin with DL D and ULL mode. IIn DL PUSCC, all subchhannels willl be sliced aand assigneed to three ssegments, an nd it can be e allocateed to sectoors of the same cell. [53] Thiss method utilizes u fulll-channel ddiversity byy dispenssing the alloocated subcaarriers to suubchannels. . [53] A perrmutation mmechanism is i also usedd here too minimizee the probaability of hhits and uusing frequuency diverrsity to miinimize thee performmance degraadation. Table 4-5 DL Distribuuted Subcarrrier Permuutation (FUSSC) DL and ULL Distributed Subcarrieer Permutatiion: Partiallly Used Subbchanneliza ation (PUSC C) Optional DDL and ULL Adjacentt Subcarrieer Permutattion: Advannced Moduulation andd Coding (AMMC) 55
Page 1 and 2:
THE FLORIDA STATE UNIVERSITY COLLEG
Page 3 and 4:
TABLE OF CONTENTS List of Tables…
Page 5 and 6:
5. Case study…………………
Page 7 and 8:
LIST OF FIGURES Figure 2-1 The Evol
Page 9 and 10:
LIST OF ABBREVIATIONS Abbreviation
Page 11 and 12:
PSS Portable Subscriber Station 89
Page 13 and 14:
CHAPTER ONE 1. Introduction The cel
Page 15 and 16: Table 1-1 Cont. 802.3an 2006 10GBAS
Page 17 and 18: 2.1. Introduction CHAPTER TWO 2. 3G
Page 19 and 20: 2.3. Development 3G has been in dev
Page 21 and 22: 2.5. Conclusion WAP (Wireless Appli
Page 23 and 24: IEEE 802.11n is the newest standard
Page 25 and 26: Table 3-3 Cont. 10 2.457 X Y Y Y Y
Page 27 and 28: 3.3.1.2. PLCP and PMD The physical
Page 29 and 30: Noise Codes). The most powerful con
Page 31 and 32: Figure 3-5 CCK Modulation HR-DSSS P
Page 33 and 34: other problem is inter-carrier inte
Page 35 and 36: Tab ble 3-5 OFDDM Modulaation and D
Page 37 and 38: and contains DSSS, CCK, PBCC (Packe
Page 39 and 40: 3.3.2. MAC Layer 3.3.2.1. Introduct
Page 41 and 42: Virtual channel sensing he other me
Page 43 and 44: SIFS (Short InterFrame Spacing) Fig
Page 45 and 46: Figure 3-20 WEP Frame and Operation
Page 47 and 48: 3.4.2. MIMO (Multiple-Input/Multipl
Page 49 and 50: 4.1. The background of IEEE 802.16
Page 51 and 52: The working groups of WiMax Forum a
Page 53 and 54: Table 4-1 Thee Basic Datta of IEEE
Page 55 and 56: Figure 4-1 The Layer Structure of I
Page 57 and 58: codes ( (CTC) and low densityy pari
Page 59 and 60: 4.3.1.2.2. AAS (Advanced Antenna Sy
Page 61 and 62: Best-effort service (BE) This schem
Page 63 and 64: Encryption Figure 4-4 PKM Protocol
Page 65: 4.3.2. IEEE 802.16e-2005, the newes
Page 69 and 70: the uplink bandwidth periodically f
Page 71 and 72: Figure 4-7 Coverage and Capacity fo
Page 73 and 74: CHAPTER FIVE 5. Case study This cha
Page 75 and 76: increased bandwidth, fixed connecti
Page 77 and 78: Figure 5-3 Landis Green Figure 5-4
Page 79 and 80: Table 5-2 Xirrus XS-3700 AP Technol
Page 81 and 82: • Automatic Tx power selection
Page 83 and 84: Table 5-4 Cont. 71
Page 85 and 86: 5.1.3. Analysis The FSU wireless ne
Page 87 and 88: since the January 2006. The populat
Page 89 and 90: Table 5-5 Parameters of WLAN and Me
Page 91 and 92: Table 5-6 Features of Nortel Wirele
Page 93 and 94: • -101 dBm typical @ 1 Mbps Recei
Page 95 and 96: Operating environment specification
Page 97 and 98: uilding density, high population de
Page 99 and 100: epeater r is developping and it wil
Page 101 and 102: Figure 5-17 WiBro Features The data
Page 103 and 104: Figure 5-19 U-RAS Premium Figure 5-
Page 105 and 106: In KT’s recent report, 60% of sub
Page 107 and 108: Figure 5-21 An Example Application
Page 109 and 110: Name Parameters Standard Table 5-10
Page 111 and 112: WiFly used Wi-Fi to cover 60% of th
Page 113 and 114: BIBLIOGRAPHY [01]. IEEE 802.11 offi
Page 115 and 116: [37]. Sun, Y.; "Bandwidth-efficient
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[88]. Mineno T.; Babji T.,"Issues a
Page 119 and 120:
[117]. Yun Z.; Yuguang F., "Securit
Page 121 and 122:
Network Operations and Management S
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