Ronald Raulefs

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Fifth-generation (5G) networks will be the first generation to benefit from location information that is sufficiently precise to be leveraged in wireless network design and optimization. We argue that location information can aid in addressing several of the key challenges in 5G, complementary to existing and planned technological developments. These(More)
In this paper, we apply two different types of space-time block codes (STBC) in the downlink of a broadband mobile radio air interface based on MCCDMA, which is a promising candidate for a 4 generation mobile radio system. The first type are ”STBCs from orthogonal designs”. For 2 TX-antennas, this is the wellknown ”Alamouti”-scheme. These STBCs are compared(More)
5G networks will be the first generation to benefit from location information that is sufficiently precise to be leveraged in wireless network design and optimization. We argue that location information can aid in addressing several of the key challenges in 5G, complementary to existing and planned technological developments. These challenges include an(More)
In this paper, we investigate broadband OFDM systems which apply beamforming in combination with different space–time diversity techniques. Various beamforming scenarios with transmitter and/or receiver sided beamforming are considered. Space–time diversity is obtained by cyclic delay diversity (CDD) in order to artificially shape the spectrum of the(More)
Wireless communications and navigation have different constraints to cope with. On the one hand, communication systems traditionally aim at high spectral efficiency with specific requirements such as low latency and low power consumption. On the other hand, navigation is usually based on the transmission of known data signals at low data rates with fine(More)
We investigate rotated Walsh-Hadamard spreading matrices for a broadband MC-CDMA system with robust channel estimation in the synchronous downlink. The similarities between rotated spreading and signal space diversity are outlined. In a multiuser MC-CDMA system, possible performance improvements are based on the chosen detector, the channel code, and its(More)
Mobile terminal location is an information which is available in mobile cellular systems. Location-based inter-cell interference coordination and synchronization are studied here for the 3GPP Long Term Evolution mobile cellular system. The impact of positioning inaccuracy is also evaluated.