Karl-Dirk Kammeyer

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In rich-scattering environments layered space-time architectures like the BLAST system may exploit the capacity advantage of multiple antenna systems. In this paper, we present a novel, computationally efficient algorithm for detecting V-BLAST architectures with respect to the MMSE criterion. It utilizes a sorted QR decomposition of the channel matrix and(More)
In recent publications the use of lattice-reduction for signal detection in multiple antenna systems has been proposed. In this paper, we adopt these lattice-reduction-aided schemes to the MMSE criterion. We show that an obvious way to do this is infeasible and propose an alternative method based on an extended system model, which in conjunction with simple(More)
1 Abstract In some recent papers new algorithms for blind adaptive equalization were proposed. These algorithms are based on the stochastic gradient method and thus can be regarded as a blindd counterpart to the classic LMS-(least mean squares-) algorithms. It is well-known that these algorithms show relatively slow convergence speed. The classic solution(More)
Theoretical and experimental studies have shown that layered space-time architectures like the BLAST system can exploit the capacity advantage of multiple antenna systems in rich-scattering environments. In this paper, we present a new efficient algorithm for detecting such architectures with respect to the MMSE criterion. This algorithm utilizes a sorted(More)
Recently the use of lattice-reduction for signal detection in multiple antenna systems has been proposed. In this paper, we adopt these lattice-reduction aided schemes to the MMSE criterion. We show that an obvious way to do this is suboptimum and propose an alternative method based on an extended system model. In conjunction with simple successive(More)
In this paper we present an analysis of the generalized sidelobe canceller (GSC). It can be shown that the theoretical limits of the noise reduction performance depend only on the autoand crossspectral densities of the input signals. Furthermore, we compute the limits of the noise reduction performance for the theoretically determined diffuse noise field,(More)
Relays in wireless networks can be used to decrease transmit power while additionally increasing diversity. Distributed turbo coding as a special case of decode-and-forward is very powerful in relay networks when assuming error free decoding in the relay. In practical wireless networks, however, this assumption is only justifiable if an ARQ protocol is(More)
In 1994, an eigenvector solution to the problem of blind equalization of possibly mixed-phase linear time-invariant transmission channels was published in this journal. Unfortunately, this solution is ambiguous on a certain condition. In this paper, we introduce a novel iterative method termed EigenVector Algorithm for blind equalization (EVA), which not(More)
In this contribution we introduce a new implementation of superdirective beamformers. The new structure has the advantage of reduced computational complexity. This advantage is due to a GSClike (Generalized Sidelobe Canceller) scheme. Unlike the conventional GSC, the filters in the sidelobe cancelling path are fixed and can be computed in advance by using(More)