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@PHDTHESIS{Koep:764234,
      author       = {Koep, Niklas},
      othercontributors = {Mathar, Rudolf and Rauhut, Holger},
      title        = {{Q}uantized compressive sampling for structured signal
                      estimation; 1},
      school       = {RWTH Aachen University},
      type         = {Dissertation},
      address      = {Aachen},
      publisher    = {Mainz},
      reportid     = {RWTH-2019-06704},
      isbn         = {978-3-95886-291-3},
      pages        = {1 Online-Ressource (x, 189 Seiten) : Illustrationen},
      year         = {2019},
      note         = {Veröffentlicht auf dem Publikationsserver der RWTH Aachen
                      University; Dissertation, RWTH Aachen University, 2019},
      abstract     = {This thesis investigates different approaches to enable the
                      use of compressed sensing (CS)-based acquisition devices in
                      resource-constrained environments relying on cheap,
                      energy-efficient sensors. We consider the acquisition of
                      structured low-complexity signals from excessively quantized
                      1-bit observations, as well as partial compressive
                      measurements collected by one or multiple sensors. In both
                      scenarios, the central goal is to alleviate the complexity
                      of sensing devices in order to enable signal acquisition by
                      simple, inexpensive sensors. In the first part of the
                      thesis, we address the reconstruction of signals with a
                      sparse Fourier transform from 1-bit time domain
                      measurements. We propose a modification of the binary
                      iterative hard thresholding algorithm, which accounts for
                      the conjugate symmetric structure of the underlying signal
                      space. In this context, a modification of the hard
                      thresholding operator is developed, whose use extends to
                      various other (quantized) CS recovery algorithms. In
                      addition to undersampled measurements, we also consider
                      oversampled signal representations, in which case the
                      measurement operator is deterministic rather than
                      constructed randomly. Numerical experiments verify the
                      correct behavior of the proposed methods. The remainder of
                      the thesis focuses on the reconstruction of group-sparse
                      signals, a signal class in which nonzero components are
                      assumed to appear in nonoverlapping coefficient groups. We
                      first focus on 1-bit quantized Gaussian observations and
                      derive theoretical guarantees for several reconstruction
                      schemes to recover target vectors with a desired level of
                      accuracy. We also address recovery based on dithered
                      quantized observations to resolve the scale ambiguity
                      inherent in the 1-bit CS model to allow for the recovery of
                      both direction and magnitude of group-sparse vectors. In the
                      last part, the acquisition of group-sparse vectors by a
                      collection of independent sensors, which each observe a
                      different portion of a target vector, is considered.
                      Generalizing earlier results for the canonical sparsity
                      model, a bound on the number of measurements required to
                      allow for stable and robust signal recovery is established.
                      The proof relies on a powerful concentration bound on the
                      suprema of chaos processes. In order to establish our main
                      result, we develop an extension of Maurey’s empirical
                      method to bound the covering number of sets which can be
                      represented as convex combinations of elements in compact
                      convex sets.},
      cin          = {613410},
      ddc          = {621.3},
      cid          = {$I:(DE-82)613410_20140620$},
      typ          = {PUB:(DE-HGF)11 / PUB:(DE-HGF)3},
      doi          = {10.18154/RWTH-2019-06704},
      url          = {https://publications.rwth-aachen.de/record/764234},
}