—This work addresses the impact of sensing decision fusion rules and operative constraints on the performance of hard decision cooperative spectrum sensing schemes for cognitive radio networks. The work focuses on cooperative spectrum sensing under two sensing operating modes: the Constant False Alarm Rate (CFAR) and the Constant Detection Rate (CDR) mode.… (More)
A multiple-access channel where point processes are randomly transformed by timing channels and then superposed is considered. An achievable rate region for the K-user channel is established. A single-user achievable rate in the presence of “many” interfering users is proposed. Results are applied to exponential server timing channels.
In this paper we deal with the problem of minimizing the complexity of an IR-UWB system by the introduction of Time-Reversal, under a power constraint and fixing a reachable performance in terms of BER. An approximate trade-off in the choice of the number of taps at the transmitter and the number of fingers at the receiver is proposed.
Traditionally paired with impulsive communications, time-hopping code-division multiple access (TH-CDMA) is a multiple access technique that separates users in time by coding their transmissions into pulses occupying a subset of N<sub>s</sub> chips out of the total N included in a symbol period, in contrast with the traditional direct-sequence CDMA… (More)
Massive MIMO is, in general, severely affected by pilot contamination. As opposed to traditional detectors, we propose a group-blind detector that takes into account the presence of pilot contamination. While sticking to the traditional structure of the training phase, where orthogonal pilot sequences are reused, we use the excess antennas at each base… (More)
When paired with traditional channel estimation and detection, massive MIMO is severely affected by pilot contamination. While sticking to the traditional structure of the training phase where orthogonal pilot sequences are reused in different cells, we propose a group-blind detector that takes into account the presence of pilot contamination. Our detector… (More)
—Millimeter wave communications will use large bandwidth and experience severe attenuation due to the pathloss. The two above conditions may force the communication system to enter the so-called wideband regime, where transmitted signals must be increasingly " peaky " in order to achieve a large fraction of the wideband capacity. This paper investigates… (More)
—A model describing the cumulative effect of the independent access of K users to a shared resource, which is formed by N elements, is proposed, based on which an integer interference measure ζ is defined. While traditional cases can be reconducted to reference well-known results, for which ζ is either Gaussian or Poissonian, the proposed model provides a… (More)
A queue timing channel with random arrival and service times is investigated. The message is encoded into a sequence of additional delays that packets are subject to before they depart from the queue. We derive upper and lower bounds of the channel capacity for general arrival and service processes, and general load. We establish the channel capacity for… (More)