11n_WiMAX_modulations

11n_WiMAX_modulations - Modulation and Encoding g...

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Unformatted text preview: Modulation and Encoding g 40504050-403 Concepts of Wireless Data Networks AM FM Digital data and analog signal modulation Amplitude Shift Keying (ASK) Frequency Shift Keying (FSK) Phase Shift K i Ph Shif Keying (PSK) Differential Phase Shift Keying (DPSK) Quadrature Amplitude Modulation (QAM) ASK FSK GFSK 2GFSK: 2 level Gaussian Frequency Shift Keying 4GFSK: 4 level Gaussian Frequency Shift Keying PSK PSK Constellation Diagram The 4-PSK Method 4- The 4-PSK Characteristics 4- The 8-PSK Characteristics 8- DBPSK: Differential Binary Phase Shif K i Ph Shift Keying DQPSK: Differential Quadrature Phase Shif K i Ph Shift Keying The 4-QAM and 8-QAM 48constellations Time domain for an 8-QAM 8signal 1616-QAM Constellations 802.11 Coding and Modulation Spreading Code Modulation Technology 2GFSK 4GFSK 2.4 GHz DSSS Barker Code Barker Code CCK CCK DBPSK DQPSK DQPSK DQPSK Data Rate 2.4 GHz FHSS 1 Mbps 2 Mbps 1 Mbps 2 Mbps 5.5 Mbps 11 Mbps 802.11n: Higher throughput improvements using MIMO i 802.11n Frequency band: 2.4 GHz or 5 GHz 24 Data rate: up to 270 Mbps (2x2 antennas) Range: ~ 50 meters R Modulation: OFDM Use multiple antenna simultaneously MIMO Multiple in and Multiple out p p MIMO 2x2 System x1 a b s1 = x c d s 2 2 x1 = as1 + bs2 x2 = cs1 + ds2 No Reflection One Reflecting Plane Two Reflecting Planes MIMO Benifits Antenna Diversity Spatial Division Multiplexing TM RangeMax Netgear, WNR854T Up to 600 Mbps ~500 feet 500 W WiMAX: Worldwide Interoperability p y for Microwave Access WiMAX Status Frequency Band Application MAC architecture Tx scheme 802.16 Dec., 2001 , 10-66 GHz 10Fixed LOS PtMP, mesh Single carrier g only 802.16d J , June, 2004 2-11 GHz Fixed LOS PtMP, mesh Single carrier, g , 256 or 2048 OFDM 802.16e Dec. 2005 2-11GHz for fixed 2-6 GHz for mobile Fixed and mobile NLOS PtMP, mesh Single carrier, g , 256 or up to 2048 OFDM Modulation Gross data rate Range QPSK, QAM QPSK, QAM QPSK, QAM QPSK 16 QAM, QPSK 16 QAM, QPSK 16 QAM, 64 QAM 64 QAM 64 QAM 32-134.4 Mbps 32Up to 30 miles 1-75 Mbps Up to 50 miles 1-75 Mbps Up to 50 miles Topology 802.16 MAC Features Applications Residential and SOHO high speed Internet access Small and medium business WiFi hot spot backhaul QoS VoIP HDTV ...
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