A simple, fast and accurate amplitude estimation algorithm of sinusoidal signals for DSP based instrumentation is proposed. It is shown that eight samples, used in two steps, are sufficient. A ...practical analytical formula for amplitude estimation is obtained. Numerical results are presented. Simulations have been performed when the sampled signal is affected by white Gaussian noise and when the samples are quantized on a given number of bits.
Software-Defined Networking (SDN) and Cloud Computing are now two of the most adopted technologies, on which many organizations are working to enhance every day. For instance, SDN is particularly ...emerging to solve networking complexity in cloud data centers, so we see many attempts to integrate Network and Cloud Managers. In this paper, we address an integration of these two technologies, particularly a yet undiscussed combination of two popular frameworks: OpenNebula and OpenDaylight. These open source solutions are widely used for cloud management and network management, yet there are no developed modules for communication between the two. Therefore, we propose a simple way for OpenDaylight to manage OpenNebula's compute nodes, using a common component they both support: OpenvSwitch. We compared OpenNebula with the popular OpenStack cloud manager, as it is attracting more attention in both academia and industry, by evaluating some relevant time metrics and discussing the differences of the proposed technologies. Then, we deployed a test topology to conduct some traffic management techniques in this integration. Our results show that OpenNebula's deployment time as well as clean-up time is significantly lower than OpenStack, but OpenStack takes less time to the running state, besides proving the simplicity of traffic management in OpenNebula using OpenDaylight.
This paper presents the results obtained by a new multiuser detector based on the Projection Onto Convex Sets (POCS) deconvolution algorithm, in comparison with those obtained by the decorrelating ...detector, when the channel is affected by the flat Rayleigh fading and gray images are transmitted through the system. All the users transmit their information with the same power, but the spreading codes are correlated. We will investigate the fading effect on the received images and the impact of the cross-correlation of the spreading codes on the quality of the received images. In the end, several conclusions are highlighted, with respect to the level of performance achieved.
Modulation detection, one of the most important functions of a receiver in a communication system, is an intermediary step between its signal detection and demodulation. In this paper, we present the ...use of the recurrence plot analysis method (RPA) used for the detection of the modulation technique used for a wireless sensor network (WSN). We show a technique for the RPA method to detect ASK, FSK, even PSK signals using recurrence matrix or distance matrix 1. We also show the potential to detect OFDM modulations using this method. Simulation results confirm the importance of the RPA method.
On the availability of CDMA channels for secondary users Fratu, O; Halunga, S; Perju, C ...
2010 3rd International Symposium on Applied Sciences in Biomedical and Communication Technologies (ISABEL 2010),
2010-Nov.
Conference Proceeding
The present paper is analysing the occupancy of the radio spectrum for some typical CDMA communications systems. The paper presents also an analysis of how the available channel are used by the ...communications system and especially of how other available channels could be detected. As example, the paper presents also how the IMT-2000 uplink bands can be better loaded.
In nowadays wireless systems, all active users, who are sharing the same cell, would like to have the same quality of service regardless their position in the cell, fading or other obstacles that ...might be placed between them and the base station (BS). A solution for this is to use relays in order to increase the capacity, to enlarge the coverage area of a base station and to improve the overall performance of the system. In this paper, we analysed the performance of a multiuser Massive MIMO system when a decode-and-forward (DF) relay protocol is used to direct the user's data to destination. The simulations show that the relay can improve the quality of data received at the BS, but the number of active users must be corelated with the number of antennas installed at the relay.
Implementation techniques of communication protocols are something of a black art, on par with writing device drivers. The paper presents a library and a technique used for implementing an ...(incidentally mobile) communication protocol, layer 2 DECT. The defining feature of this software library is support for SDL-88 semantics; the result was unimaginatively named Protocols Application Development System (PADS), and can be used to develop protocols software on Unix platforms with a System V and POSIX.1b heritage. The protocol implemented can then be run in user space Unix, and/or deployed on an embedded target with support for POSIX.1b.
Propagation channel simulations for UWB communications Craciun, F.; Fratu, O.; Halunga, S.
TELSIKS 2005 - 2005 uth International Conference on Telecommunication in ModernSatellite, Cable and Broadcasting Services,
2005, Letnik:
1
Conference Proceeding
Ultra-wide band (UWB) systems with the multi-band orthogonal frequency division multiplexing techniques (ODFM) represent a promising technology for future high-speed networks. The paper describes a ...line of sight channel propagation model compatible with the one purpose by IEEE 802.15.3a standardization group and a modality to simulate it. The simulated channel was proposed for multi-band OFDM based UWB systems, highlighting a number of multipath channel parameters: RMS delay spread, power decade profile and number of paths (defined as the number of arrived signals that have a level with maximum 10 dB below the level of the strongest arrived signal).
This ultra wideband (UWB) communication system proved to be a new and reliable system for wireless communications due to its capacity to provide low power, short range high date rate, fade free, ...relatively shadow-free communications in a device multipath environment. We analyze these performances for three different UWB block waveforms communication systems.
The paper describes a library and a technique used for implementing a mobile communication protocol, starting from the layer 2 DECT specification. The defining feature of this software library is ...support for SDL-88 semantics. This library can be used to develop protocols software on Unix platforms with a system V and POSIX.1b heritage. The protocol implemented can then be run in user space Unix, and/or deployed on an embedded target with support for POSIX.1b.
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