Mobile communication is developing toward wideband and personalizing. Some new wireless technologies spring up in quantities and standardization is accelerated. As the enhanced version of WCDMA, HSDPA highly boosts the downlink data rate with peak value lOMbps. Buy cheap nike shoes is very smart!As the evolution of 3G standard, LTE adopts OFDM/MIMO as core technologies. Its upload speed can reach 50Mbps and download speed is up to lOOMbps. Do you like those cheap men's nike shoes?As to the time-varying characteristics of wireless channel, HSDPA and LTE system adopt adaptive modulation and coding (AMC) and hybrid ARQ as two main link adaptive technologies. They can fully use the spectrum resource and boost data rate in the precondition that QoS is guaranteed.I love northface jackets.Chapter 2 studies wireless channel modeling. Firstly channel characteristics of single-carrier and OFDM system are analyzed, and then the corresponding simulation modeling is presented. Three kinds of SOS simulation method for flat fading channel as follows are compared: straight simulation, Jakes modelingand improved Jakes modeling. And simulation result shows that statistical characteristic of improved Jakes modeling is much closer to the ideal value. Based on the discussion above, A tapped-delay-line model and three kinds of simulation method for OFDM channel are exhibited.Chapter 3 studies the key technologies in AMC and HARQ system. Based on the construction method of RC-LDPC, six kinds of MCS are abtained. PHY abstraction theory is deeply researched and RBIR, EESM as well as mean value methods are evaluated by simulation.
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