Adaptivity on an OFDM fixed wireless access system

A.D. Valkanas1, P.I. Dallas1, G.J. Karachalios1, A.D. Poularikas2
1Advanced Modulation and Coding Group Development Programmes Department, Intracom S.A., Athens, Greece
2Electrical and Computer Engineer Department, University of Alabama Huntsville, Huntsville, AL, USA

Tóm tắt

A special characteristic of multicarrier modulation techniques such as OFDM is that they can assign different modulation schemes to each subcarrier according to a reception quality measurement such as the signal-to-noise ratio (SNR) on a subcarrier. This process allocates different bits to subcarriers and is further known at the literature as bit loading. In the paper, a bit-loading algorithm has been modified to take into account the presence of variable location pilots in each OFDM symbol. The target of this enhancement is to measure the system performance increase and the bandwidth efficiency improvement obtained. The study has been done for a broadband fixed wireless system.

Từ khóa

#OFDM modulation #Modulation coding #System performance #Costs #Fading #Iterative algorithms #Channel capacity #Electric variables measurement #Signal to noise ratio #Bandwidth

Tài liệu tham khảo

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