Very interesting article from Tech-On. LTE shows a lot of promise because of its ability to scale speed based on available bandwidth, low transmit power based on single-carrier FDMA on the transmit side, and short connection delays. Speeds can be as high as 100 Mbps using a 20 MHz bandwidth, and could conceivably reach 1 Gbps on 4G bandwidth allocations of 100 MHz. The upside of its usage of SC-FDMA in the uplink (as opposed to OFDM) is low transmit power. The downside is, how to implement waveform equalization. (See this paper by Freescale: http://www.freescale.com/files/wireless_comm/doc/white_paper/3GPPEVOLUTIONWP.pdf). Equalizer complexity and chip area increases with data rate and has been impractical until now for those kinds of transmission speeds. 32-nm or finer CMOS technologies are expected to be available by 2012 or so, which would make it feasible to integrate waveform equalization on-chip.
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