Multicarrier Wireless Systems with Adaptive Decision Combining

Multicarrier Orthogonal Frequency Division Multiplexing (OFDM) systems with decision combining are considered in this thesis. It is shown that such systems can provide enhanced bit error rates. However, this occurs at the cost of data throughput of the system. The typical system considered essentially involves transmission of redundant data over subsets of the total number of subcarriers available for the entire system. The partial decisions in each of these subsets are then combined into overall decisions about the transmitted data. Simple decision combining strategies such as AND, OR, Majority Logic (ML) and more complex adaptive decision combining that takes into account the fading estimates over the subcarriers of the system are considered. Analytical expressions for estimation of bit error rates in such systems have been derived and parameters that influence the performance are identified. We consider several fading situations and assume an additive, white gaussian noise(AWGN) channel. Computer simulations of bit error rate performance for a variety of multicarrier OFDM systems with decision combining are presented and compared with the performance of systems without decision combining.

Name thesis:degree_name

M Eng Sci

Discipline thesis:degree_discipline

Electrical and Computer Engineering

Grantor dc:publisher

The University of Western Ontario

Year dc:date.issued

2003

Author dc:creator

• Geevarghese, Rexy J.

Advisor dc:contributor.advisor

• Rao, R.K.

• OFDM
• BER
• frequency diversity
• decision combining
• fading

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/20.500.14721/38865

OAI identifier oai:identifier

oai:uwo.scholaris.ca:20.500.14721/38865