Wireless LAN White Papers
Rate and Power Adaptation in OFDM With Quantized Feedback
Overview Adaptive modulation can be used in conjunction with Orthogonal Frequency Division Multiplexing (OFDM) to obtain high spectral efficiencies. This paper analyzes two types of adaptive OFDM systems with quantized feedback. In the first type, rate and power allocation algorithm is performed at the transmitter to maximize throughput using quantized Channel-to-Noise Ratio (CNR) feedback from the receiver. In the second type, power allocation is implicit such that the receiver decides the constellation to be used in each subcarrier and sends back only the rate allocation vector to the transmitter. The paper determines the spectral efficiency of these adaptive OFDM systems and quantifies the number of bits of feedback needed in each case.
| Publisher | Indian Institute of Technology Madras | File Format | |
|---|---|---|---|
| Date Published | April 2007 | ||
| Format | White Papers | ||
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