853 research outputs found
Purposeful Co-Design of OFDM Signals for Ranging and Communications
This paper analyzes the fundamental trade-offs that occur in the co-design of
orthogonal frequency-division multiplexing signals for both ranging (via
time-of-arrival estimation) and communications. These trade-offs are quantified
through the Shannon capacity bound, probability of outage, and the Ziv-Zakai
bound on range estimation variance. Bounds are derived for signals experiencing
frequency-selective Rayleigh block fading, accounting for the impact of limited
channel knowledge and multi-antenna reception. Uncompensated carrier frequency
offset and phase errors are also factored into the capacity bounds. Analysis
based on the derived bounds demonstrates how Pareto-optimal design choices can
be made to optimize the communication throughput, probability of outage, and
ranging variance. Different signal design strategies are then analyzed, showing
how Pareto-optimal design choices change depending on the channel
Channel Estimation for MIMO MC-CDMA Systems
The concepts of MIMO MC-CDMA are not new but the new technologies to improve
their functioning are an emerging area of research. In general, most mobile
communication systems transmit bits of information in the radio space to the
receiver. The radio channels in mobile radio systems are usually multipath
fading channels, which cause inter-symbol interference (ISI) in the received
signal. To remove ISI from the signal, there is a need of strong equalizer. In
this thesis we have focused on simulating the MIMO MC-CDMA systems in MATLAB
and designed the channel estimation for them
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