114 documents found, page 1 of 12

Critical reflections on tourism: Phenomenological perspectives on global-South,...

From a critical phenomenology perspective, it is possible to interpret tourism as an open arena where different players interact, thus illustrating the rationale behind their epistemic positioning. Tourism, as an economic sector, is both a product and a producer of what is happening at global level. This to-and-from mutual determinations may be exemplified by visual aids that help to map the conceptual models t...

Political economy and contemporary Renaissance: Challenges and opportunities

In times of severe crisis there are emergence phenomena, which are characterized by disruptive rethinking of previous, taken for granted assumptions. The aims of the present text are to explore the role played by the field of political economy scientific production as a relevant contribution to foster the debate about contemporary societies’ Renaissance phenomena, at the level of the prevailing cosmogonies that...

Alamouti coding scheme and virtual array concept for joint radar and communicat...

This paper focuses on the integration of radar and communication (RadCom) systems on a common platform. We consider a scenario with multiple transmit and receive antennas, where the integration of the two functionalities is achieved through the use of Alamouti coding and OFDM waveform. It is shown that by using the Alamouti coding scheme, the spatial diversity order is improved as in legacy communication system...

Iterative Multiuser Equalization for Subconnected Hybrid mmWave Massive MIMO Ar...

Millimeter waves and massive MIMO are a promising combination to achieve the multi-Gb/s required by future 5G wireless systems. However, fully digital architectures are not feasible due to hardware limitations, which means that there is a need to design signal processing techniques for hybrid analog-digital architectures. In this manuscript, we propose a hybrid iterative block multiuser equalizer for subconnect...

Retrospective Interference Alignment: Degrees of Freedom Scaling With Distribut...

In this paper, we consider the K-user singleinput single-output interference channel with delayed channel state information at the transmitters (CSIT). Our main contribution is to show that even with delayed CSIT and distributed transmitters, the achievable degrees of freedom (DoFs) still scale with the number of users. More specifically, we propose a method that achieves K/(2 √K −1) ≥ √K/2 DoF. The main idea b...

Hybrid Iterative Space-Time Equalization for Multi-User mmW Massive MIMO Systems

The combination of millimeter wave (mmW) with massive MIMO is a promising approach to achieve the multi Gb/s required by future wireless systems. Fully digital architectures are not feasible due to hardware limitations, and thus, the design of signal processing techniques for hybrid analog-digital architectures is of paramount importance. In this paper, we propose a new hybrid iterative block space-time receive...

Parametrization and Applications of Precoding Reuse and Downlink Interference A...

In this paper, we consider the downlink communication of an arbitrary number of transmitters over broadcast interference channels. In order to suppress interference, we investigate a network-level linear precoding scheme dubbed precoding reuse. Such a technique is leveraged on the interference alignment (IA) principle, where the undesired signals overlap in a reduced-dimension subspace at the receivers. Precodi...

An Overview on Resource Allocation Techniques for Multi-User MIMO Systems

Remarkable research activities and major advances have been occurred over the past decade in multiuser multiple-input multiple-output (MU-MIMO) systems. Several transmission technologies and precoding techniques have been developed in order to exploit the spatial dimension so that simultaneous transmission of independent data streams reuse the same radio resources. The achievable performance of such techniques ...

Fragmento de cerâmica para encerramento de diastema: caso clínico

Retrospective Interference Alignment for the K-User M × N MIMO Interference Cha...

In this paper, we consider a K-user M × N MIMO interference channel, with outdated channel state information at the transmitters (CSIT). Based on the technique introduced by Cadambe and Jafar, for the IC with perfect and up-to-date CSIT, we propose and analyze a scheme that guarantees interference alignment with outdated CSIT. The interference is aligned by the transmitters, and removed by the receivers using z...