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In this paper, we experimentally demonstrate a real-time software defined multiple input multiple output (MIMO) visible light communication (VLC) system employing link adaptation of spatial multiplexing and spatial diversity. Real-time MIMO signal processing is implemented by using the Field Programmable Gate Array (FPGA) based Universal Software Radio Peripheral (USRP) devices. Software defined implantation...
The Argentinian Space Agency (CONAE) has been pursuing the development of segmented satellite architectures as a novel strategy to reduce the cost and improve responsiveness of space access. Among the key enablers for these architectures, wireless communication is likely to be the most critical as it requires to operate on a highly dynamic, sparse and extreme environments. In this work, we analyze...
To describe the transmission performance of LTP protocol more intuitively and accurately, it is an original work to model the transfer procedure of a single LTP session, and analyze the expected file delivery time of a data block theoretically. In order to improve the data transmission efficiency in extreme long and error-prone deep space links, an asynchronous accelerated retransmission strategy...
This paper evaluates the deployment of a wireless sensor network (WSN) to support and speed-up the assembly, integration and test activities in a satellite project. We focus on the thermal vacuum tests, which come along with an extensive amount of sensors to monitor the thermal behavior of the spacecraft. Recent work revealed a great potential; however, the focus was on passive technologies based...
Wireless Sensor Networks (WSNs) is a special category of Wireless Ad-Hoc Networks where low-powered wireless nodes are deployed in specific areas either in a random or predetermined manner, in order to sense an event and transmit the collected data to a central node for processing (sink). Due to the fact that the wireless sensor nodes are low-powered and with limited processing and storage capabilities,...
Wireless sensor networks for aerospace applications need to provide reliable communications with guaranteed real-time functionality in order to serve the requirements of especially the flight control domain. Additionally, the communication system needs to be energy-efficient to enable autonomous operation of wireless sensors. The environment is challenging for wireless communication regarding the...
In this work the design of low power infrared transceiver ASIC with AMS350nm technology is presented. There are two different types of transceiver designs that have been developed. The first design is based on IrDA 9600 baud serial infrared (SIR) standard physical signal layer that uses split-phase Manchester coding technique and the second design is using uni-polar return zero coding (RZ) technique...
In this paper we study a wireless passive sensor network. The sensors are deployed to estimate the true values of multiple active target signals. The sensors forward their observation to a fusion center, which processes the observation of each sensor by a set of fusion rules. One achievement of this paper is proposing an unbiased estimator with minimized variance of errors. To do so, we optimize both...
This paper regards a network of wireless passive sensors, suitable for radar applications. The network observes multiple number of target signals to be estimated. We propose an unbiased estimator whose error is minimized by optimizing both the power allocation at sensor nodes and the fusion coefficients at the fusion center. Since the underlying optimization problems are subject to both the individual...
The deep-space Ka-band channels are very sensitive to the weather conditions of the ground station area, where the data link will be suffered by high dynamic bit error rate and even occurred random interruption. Moreover, the huge distance of the deep-space communications caused that the transmitter can only have delayed channel state information (CSI) feedback. We modeled the noise temperature of...
Data Center (DC) servers consume a huge amount of energy. However, a part of this energy (cooling and information technology devices) can be saved by shutting down racks containing idle servers. This can be achieved by rerouting workloads from partially loaded racks, and thus allowing additional racks to switch into idle mode. Workload rerouting requires additional wired links or by optical wireless...
Data Centers (DC) consume an enormous amount of energy, now accounting for about 1.5% of US electrical usage. However, part of this energy (server operation and cooling) can be saved by turning off idle servers. This can be achieved by rerouting workloads from partially loaded servers, and thus allowing additional idle servers to shut down. Workload rerouting could be done by optical wireless communication...
Light-Fidelity (LiFi) is the communication technology, which utilizes LEDs for both illumination and data transmission with a bidirectional link. In order to enhance the users mobility for indoor or outdoor environment, it is essential to choose the most appropriate receiver. LiFi systems suffer of a lack of receiver solutions about two great LiFi problematics: the integration of the receiver into...
Technological advances in the miniaturization of millimeter-sized sensor motes facilitate new application cases where the motes' inherent energy constraints enforce radical changes with respect to the sensors' communication procedures. An upcoming application scenario is the surveying and exploration of hardly permeable and hardly accessible underground environments such as those of oil-sand mining...
Routing in Delay-/Disruption-Tolerant Networking (DTN) has long been recognized as a challenging research topic. The difficulty lies in the fact that link intermittency and network partitioning, possibly coupled with long delays, prevent the use of Internet solutions based on an up-to-date comprehensive knowledge of network topology, as communicated by routing protocols. In the literature on DTN routing,...
Implementation of network coding (NC) is expanding to a diverse set of networks due to the flexible design provided through its use, enabling a trade-off between robustness and spectral efficiency. In this paper, we investigate the application of NC in delay tolerant networks (DTN) through the use of software defined radio (SDR) nodes. We specifically focus on a deep space network scenario with large...
A chipless RFID tag that exhibits a variable cross-polar response depending on its orientation with respect to the probing wave is investigated as a potential candidate for realizing an angular rotation sensor. The chipless sensor can be employed in harsh environments due to the absence of any silicon chip.
The problems of operation of homodyne system of radio frequency identification and localization are discussed. The presence of microwave reflectivity of the body, the tag is placed onto, disturbs the operation of homodyne system in a part of tag localization by distortion of the signal from transponder. In presented paper the negative influence of body cross-section on accuracy of distance measurement...
Mobile Ad-hoc Networks (MANETs) are one possible solution for infrastructure-independent communication in disaster scenarios. In such scenarios, communication is essential to coordinate first responders and safe lives. But mobile nodes in large areas face several challenges related to connectivity, resulting in frequent partitions and intermittent connections. Protocols as well as network access technologies...
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