الفهرس 
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Abstract
Most existing transceivers are DFT-centric where complex sinusoids play a central role in the internals of the core building blocks.from the channel perspective,complex sinusoids constitute the fundamental building blocks in the wireless baseband equivalent channel model;exemplified by the time-varying transfer function.In addition,complex sinusoids are used as signaling waveforms for data transmission through the channel.The dominant mode of transmission in modern communications is in the form of finite length blocks having approximately finite bandwidth.As a result,the time-frequency space becomes projected to an essentially limited time and frequency subspace where complex sinusoids suffer from leakage effects due to the finite time extent of a block. In addition,Kronecker delta signals (duals of complex sinusoids) suffer from the same vulnerability due to the finite extent bandwidth.Gabor signaling bases using non-rectangular pulse shapes can attain good confinement in the time-frequency spread,however, at the expense of completeness which reduces the utilization efficiency of the time-frequency signaling resources.Over a signaling block,period a doubly dispersive (DD) channel is projected onto an essentially limited time-frequency subspace.In this subspace, the DPS basis matched to the channel parameters is known to be optimally compact in representing the channel using a basis expansion decomposition. Unlike the DFT basis that lacks compactness due to the leakage effect.The leakage in the coefficients of the channel expansion using the DFT basis has a direct correspondence with the ISI between the DFT components of the signal transmitted thought the channel.For the DPS basis,however,the correspondence is not as obvious. Nevertheless DPS when used for signaling results in ISI compactness in the form of an exponential decay of distant ISI components.The efficacy of DPS signaling in DD channels in addition to its efficiency in modeling DD channels motivates the investigation of a new transceiver baseband architecture where DFT is supplanted with DPS.