Prim's and Kruskal's algorithms are two common approaches for finding a minimum spanning tree (MST) in a weighted, undirected graph. Prim's algorithm grows the MST from a single starting vertex by iteratively adding the lowest-cost edge that connects the MST to another vertex. Kruskal's algorithm considers all edges in order of weight and adds edges to the MST if they do not form cycles. Both run in O(E log E) time, where E is the number of edges, and are greedy algorithms that work to find the optimal MST solution.
The document discusses minimum spanning trees (MSTs). It defines MSTs and provides examples of applications like wiring electronic circuits. It then describes two common algorithms for finding MSTs: Kruskal's algorithm and Prim's algorithm. Kruskal's algorithm finds MSTs by sorting edges by weight and adding edges that connect different components without creating cycles. Prim's algorithm grows an MST from a single vertex by always adding the lowest-weight edge connecting a vertex to the growing tree.
Modified e-slotted patch antenna for WLAN/Wi-Max satellite applicationsTELKOMNIKA JOURNAL
A low profile modified e-slotted microstrip antenna is proposed for multiple wireless communication applications. The performance of antenna is measured in terms of return loss, current distribution. The effect of variation of height of substrate on antenna impedance bandwidth is also studied. The antenna with overall size 30×50×.8m.m.3 resonates at eight frequencies which covers some important applications like GPS, wireless local area network (WLAN), worldwide interoperability for microwave access (WiMax), Satellite communication etc. The proposed antenna structure offers great advantages due to compact size, simple structure and multiple applications. The multi band antenna was designed and optimized using ansoft HFSS v13 simulator. The simulated result is good agreement with measured result.
As we have realized in the class of Graph Algorithms, many problems can be represented as a graph. For example, we could be a electrical machine company with different possible sources of parts to the production of a particular engine.
Therefore, we want to minimize the transit between node in the graph.... we can use the Minimum Spanning Tree to obtain a really efficient distribution tree.
6161103 2.8 force vector directed along a lineetcenterrbru
1) A force vector acting along a line between two points can be represented as a Cartesian vector using the position vector r from one point to the other and the unit vector u=r/r.
2) Example problems show calculating the force vectors for cables supporting structures by determining r between the cable endpoints, taking the unit vector, and multiplying by the force magnitude.
3) The resultant force on a wall hook supported by two cables was found by adding the Cartesian force vectors for each cable.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
An approach to design a rectangular microstrip patch antenna in s band by tlm...prjpublications
This document describes the design of a rectangular microstrip patch antenna operating in the S band (2-4 GHz) using the transmission line model. Key steps included calculating antenna parameters like width, effective dielectric constant, and length based on the transmission line model. An inset feed was used for impedance matching. Simulation results showed the input impedance matched the 50 ohm feed at the design frequency of 2.4 GHz. The return loss was minimized (-169.4 dB) and VSWR was close to the ideal value of 1, indicating good impedance matching. The antenna was concluded to be well designed for operation in the S band with a bandwidth of 4.16%.
Prim's and Kruskal's algorithms are two common approaches for finding a minimum spanning tree (MST) in a weighted, undirected graph. Prim's algorithm grows the MST from a single starting vertex by iteratively adding the lowest-cost edge that connects the MST to another vertex. Kruskal's algorithm considers all edges in order of weight and adds edges to the MST if they do not form cycles. Both run in O(E log E) time, where E is the number of edges, and are greedy algorithms that work to find the optimal MST solution.
The document discusses minimum spanning trees (MSTs). It defines MSTs and provides examples of applications like wiring electronic circuits. It then describes two common algorithms for finding MSTs: Kruskal's algorithm and Prim's algorithm. Kruskal's algorithm finds MSTs by sorting edges by weight and adding edges that connect different components without creating cycles. Prim's algorithm grows an MST from a single vertex by always adding the lowest-weight edge connecting a vertex to the growing tree.
Modified e-slotted patch antenna for WLAN/Wi-Max satellite applicationsTELKOMNIKA JOURNAL
A low profile modified e-slotted microstrip antenna is proposed for multiple wireless communication applications. The performance of antenna is measured in terms of return loss, current distribution. The effect of variation of height of substrate on antenna impedance bandwidth is also studied. The antenna with overall size 30×50×.8m.m.3 resonates at eight frequencies which covers some important applications like GPS, wireless local area network (WLAN), worldwide interoperability for microwave access (WiMax), Satellite communication etc. The proposed antenna structure offers great advantages due to compact size, simple structure and multiple applications. The multi band antenna was designed and optimized using ansoft HFSS v13 simulator. The simulated result is good agreement with measured result.
As we have realized in the class of Graph Algorithms, many problems can be represented as a graph. For example, we could be a electrical machine company with different possible sources of parts to the production of a particular engine.
Therefore, we want to minimize the transit between node in the graph.... we can use the Minimum Spanning Tree to obtain a really efficient distribution tree.
6161103 2.8 force vector directed along a lineetcenterrbru
1) A force vector acting along a line between two points can be represented as a Cartesian vector using the position vector r from one point to the other and the unit vector u=r/r.
2) Example problems show calculating the force vectors for cables supporting structures by determining r between the cable endpoints, taking the unit vector, and multiplying by the force magnitude.
3) The resultant force on a wall hook supported by two cables was found by adding the Cartesian force vectors for each cable.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
An approach to design a rectangular microstrip patch antenna in s band by tlm...prjpublications
This document describes the design of a rectangular microstrip patch antenna operating in the S band (2-4 GHz) using the transmission line model. Key steps included calculating antenna parameters like width, effective dielectric constant, and length based on the transmission line model. An inset feed was used for impedance matching. Simulation results showed the input impedance matched the 50 ohm feed at the design frequency of 2.4 GHz. The return loss was minimized (-169.4 dB) and VSWR was close to the ideal value of 1, indicating good impedance matching. The antenna was concluded to be well designed for operation in the S band with a bandwidth of 4.16%.
Proposed P-shaped Microstrip Antenna Array for Wireless Communication Applica...TELKOMNIKA JOURNAL
In this paper a P-shaped microstrip antenna array is proposed for X-band applications in the
frequency range (8.1567-9.3811) GHz .The gain obtained in this frequency range is about 8.305 dBi.
The reflection coefficient is less than - 10 dB in the above frequency range. The simulation results were
obtained for the optimum parameters using the CST software while the practical test was carried out using
Vector Network Analyzer (VNA). The microstrip antenna was manufactured using FR-4 substrate with
relative dielectric constant of 4.3 and loss tangent 푡푎푛 훿 = 0.002.The simulation and practical results were
compared. The size of the antenna array is (33 × 70 × 1.6) 푚푚3. This array is suitable for satellite
communication, radar application.
Multiband Circular Microstrip Patch Antenna for WLAN Applicationtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
This document presents a novel dual open stub and U-slot loaded square microstrip antenna design for quad-band operation between 4.37-9.40 GHz. The antenna consists of a square patch with two open stubs placed diagonally and a U-slot embedded in the center. Experimental results show the antenna resonates at four bands with impedance bandwidths between 1.7-9.25% and achieves a peak gain of 2.76 dB, which is 3.45 times higher than a conventional square microstrip antenna. The proposed antenna design is compact, uses low-cost materials, and may be suitable for wireless applications such as WLAN and systems operating in the X-band frequency range.
This document summarizes a research paper that presents a novel design of a complementary symmetry U-slot equilateral triangular microstrip antenna for pentaband operation between 1.83-8.73 GHz. The antenna is fabricated using a low-cost glass epoxy substrate and measures 8x5x0.16 cm3. It achieves a maximum bandwidth of 19.23% and peak gain of 2.19 dB. The antenna design and experimental results demonstrating its pentaband performance are described. Potential applications of the antenna include systems operating in DCS1900, IEEE 802.11a, HIPERLAN/2, and C band frequencies.
Design a mobile telephone system in a certain cityeSAT Journals
Abstract
A mobile telephone system is designed to facilitate better communication among 8000 users in the centre of Roma. The network
performance prediction tool was used to determine the best location for deployment of the base station. It was based on some
parameters or predictions which were obtained by calculating needed data to construct the base station.
Theoretically call planning, cell splitting, frequency re-use, offered traffic etc. techniques are used to obtain a good coverage for
a certain city. In order to find the best cell cluster, many calculations were also implemented.
The objective achieved was designing a network system in city centre of Roma. The 7 cell cluster and 12 cell cluster was selected
for its overall efficiency. In addition to this, co-channel interference, best server, maximum received power etc. were examined for
deployment of the base station with help of Winprop.
Key Words:Mobile telephone system, Cell cluster, Frequency re-use, Network performance, Power,Winprop.
This document introduces the exponential Pareto distribution (EPD), a new probability distribution derived from the exponential and Pareto distributions. Some key properties of the EPD are derived, including its probability density function, cumulative distribution function, moments, coefficients of variation, skewness and kurtosis. Parameter estimation for the EPD is also discussed using maximum likelihood estimation. Plots of the density, distribution, and other functions of the EPD are provided for various parameter values.
A simple, easy and flexible Defected Ground Structure (DGS) is proposed for rectangular arrays and
demonstrated theoretically in here with the aim of achieving suppression of cross polarization resulting improved
polarization purity in radiated fields. The employed DGS appears to be highly efficient in terms of suppressing
Cross Polarization especially in H-plane. A [2×2] array has been designed having aspect ratio of 1.3 and showing
14 dB enhancement in the segregation between the co-polarization to cross-polarization dissemination with
improved impedance Bandwidth.
It is a algorithm used to find a minimum cost spanning tree for connected weighted undirected graph.This algorithm first appeared in Proceedings of the American Mathematical Society in 1956, and was written by Joseph Kruskal.
The document describes the design of a cross dipole antenna for GPS applications operating at 2 GHz. The antenna consists of two orthogonal dipole elements that are fed 90 degrees out of phase to provide circular polarization. The designed antenna resonates at 2 GHz with a 500 MHz bandwidth and meets requirements of VSWR <= 3 and return loss <= -10 dB. Simulation results using HFSS software show the antenna provides circular polarization reception in the GPS band as desired.
Kruskal's algorithm is a minimum spanning tree algorithm that finds the minimum cost collection of edges that connect all vertices in a connected, undirected graph. It works by sorting the edges by weight and then sequentially adding the shortest edge that does not create a cycle. The algorithm uses a disjoint set data structure to track connected components in the graph. It runs in O(ElogE) time, where E is the number of edges.
This document discusses techniques for suppressing grating lobes in distributed subarray (DSA) antennas. It describes how grating lobes, which are unintended beams that limit system performance, are produced by the large spacing between subarrays in a DSA. The principle of pattern multiplication is introduced as a technique for reducing grating lobes by designing the transmit and receive array patterns such that nulls in one pattern coincide with grating lobes in the other pattern. Simulation results showing the grating lobe and null locations for sample transmit and receive arrays are presented, demonstrating that pattern multiplication can effectively suppress grating lobes in the combined two-way pattern.
This document summarizes a research paper on the design and development of a complementary symmetry rectangular microstrip antenna for triple wideband operation. The antenna has dimensions of 80 x 50 x 1.6 mm3 and operates between 3.96-11.56 GHz with a maximum bandwidth of 29.45%. It is fabricated on a low-cost glass epoxy substrate using a simple photolithography process. Experimental results show that the antenna achieves triple wideband operation through the use of complementary E-slots on the patch and an H-slot on the ground plane. The antenna exhibits broadside radiation characteristics with a peak gain of 2.64 dB, making it suitable for applications in C and X-band communication systems.
The document discusses minimum spanning trees (MST) and two algorithms for finding them: Prim's algorithm and Kruskal's algorithm. It begins by defining an MST as a spanning tree (connected acyclic graph containing all vertices) with minimum total edge weight. Prim's algorithm grows a single tree by repeatedly adding the minimum weight edge connecting the growing tree to another vertex. Kruskal's algorithm grows a forest by repeatedly merging two components via the minimum weight edge connecting them. Both algorithms produce optimal MSTs by adding only "safe" edges that cannot be part of a cycle.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
ABRA: Approximating Betweenness Centrality in Static and Dynamic Graphs with ...Kaushalya Madhawa
Paper presentation on ABRA: a random sampling based approximate betweenness centrality estimation method
Please find the PDF here https://drive.google.com/open?id=0BwND8Ws5fgEeTlVBejFGLW9QaFU
This document contains notes on graphing trigonometric functions. It reviews the domains, ranges, periods, maximums, minimums, and intercepts of y=sin(x), y=cos(x), and y=tan(x). It explains that compressing or stretching the period of these functions is achieved by including a coefficient b in front of x, such as y=sin(bx). Examples are provided and homework assignments are listed at the end.
This document provides a summary of a lecture on multipath fading channels for mobile communication systems. It discusses various topics related to multipath fading including shadowing (slow fading), fast fading channels, mathematical models, and probability models. Specific topics covered include the lognormal distribution of shadowing, the two ray model, modeling the wireless channel as a black box, an introduction to fast fading, and Doppler shift. References several papers on topics like fading channels, narrowband land mobile channels, and the WSSUS channel model.
1) The document discusses digital transmission of analog signals using techniques like Pulse Code Modulation (PCM), Differential Pulse Code Modulation (DPCM), and Delta Modulation (DM).
2) PCM involves sampling the analog signal, quantizing the sample amplitudes, and encoding the quantized values into binary codewords.
3) Nyquist sampling theorem states that if a signal is bandlimited to W Hz, it can be reconstructed perfectly from samples taken at a rate of at least 2W samples/second.
This document analyzes the performance of adaptive algorithms in future cellular networks using MATLAB. It discusses important cellular network parameters like cell size, number of users, co-channel reuse ratio, path loss, transmitted power, signal-to-noise ratio, bit error rate, modulation technique (QAM), frequency reuse, and relay response. It presents MATLAB programs and results that model hexagonal cell layout, co-channel reuse ratio, path loss effects, response of signal-to-interference-plus-noise ratio, and average spectral efficiency as key parameters are varied. The analysis concludes the adaptive algorithm concept and MATLAB simulations would help cellular network designers optimize performance and identify issues cost-effectively before implementation.
The document discusses enhancements to the generalized sidelobe canceller (GSC) algorithm for audio beamforming. It presents:
1) Amplitude scaling models to account for near-field effects, including a 1/r model, acoustic physics model, and statistical model. Experimental results found the acoustic physics model provided a small improvement.
2) Automatic target alignment using cross-correlation and a threshold, but experimental results found this did not improve performance over the standard GSC due to low signal-to-noise ratios.
3) Analysis of different array geometries using beamfield plots and simulations, finding array geometry has the largest impact on performance and random arrays have potential if well described.
Massive MIMO for Cooperative Network ApplicationVARUN KUMAR
This document summarizes a research paper on analyzing the achievable rate and power efficiency of massive MIMO in cooperative networks using zero-forcing receivers. It outlines the problem definition, system model, and simulation results. The system model considers uplink transmission from mobile users to a base station via relay stations. It analyzes the observed signal-to-noise ratio in direct and cooperative transmission and defines achievable rate metrics for direct, non-cooperative, and cooperative decoding schemes. Power efficiency is defined as the achievable rate divided by the total transmit power of all nodes.
Proposed P-shaped Microstrip Antenna Array for Wireless Communication Applica...TELKOMNIKA JOURNAL
In this paper a P-shaped microstrip antenna array is proposed for X-band applications in the
frequency range (8.1567-9.3811) GHz .The gain obtained in this frequency range is about 8.305 dBi.
The reflection coefficient is less than - 10 dB in the above frequency range. The simulation results were
obtained for the optimum parameters using the CST software while the practical test was carried out using
Vector Network Analyzer (VNA). The microstrip antenna was manufactured using FR-4 substrate with
relative dielectric constant of 4.3 and loss tangent 푡푎푛 훿 = 0.002.The simulation and practical results were
compared. The size of the antenna array is (33 × 70 × 1.6) 푚푚3. This array is suitable for satellite
communication, radar application.
Multiband Circular Microstrip Patch Antenna for WLAN Applicationtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
This document presents a novel dual open stub and U-slot loaded square microstrip antenna design for quad-band operation between 4.37-9.40 GHz. The antenna consists of a square patch with two open stubs placed diagonally and a U-slot embedded in the center. Experimental results show the antenna resonates at four bands with impedance bandwidths between 1.7-9.25% and achieves a peak gain of 2.76 dB, which is 3.45 times higher than a conventional square microstrip antenna. The proposed antenna design is compact, uses low-cost materials, and may be suitable for wireless applications such as WLAN and systems operating in the X-band frequency range.
This document summarizes a research paper that presents a novel design of a complementary symmetry U-slot equilateral triangular microstrip antenna for pentaband operation between 1.83-8.73 GHz. The antenna is fabricated using a low-cost glass epoxy substrate and measures 8x5x0.16 cm3. It achieves a maximum bandwidth of 19.23% and peak gain of 2.19 dB. The antenna design and experimental results demonstrating its pentaband performance are described. Potential applications of the antenna include systems operating in DCS1900, IEEE 802.11a, HIPERLAN/2, and C band frequencies.
Design a mobile telephone system in a certain cityeSAT Journals
Abstract
A mobile telephone system is designed to facilitate better communication among 8000 users in the centre of Roma. The network
performance prediction tool was used to determine the best location for deployment of the base station. It was based on some
parameters or predictions which were obtained by calculating needed data to construct the base station.
Theoretically call planning, cell splitting, frequency re-use, offered traffic etc. techniques are used to obtain a good coverage for
a certain city. In order to find the best cell cluster, many calculations were also implemented.
The objective achieved was designing a network system in city centre of Roma. The 7 cell cluster and 12 cell cluster was selected
for its overall efficiency. In addition to this, co-channel interference, best server, maximum received power etc. were examined for
deployment of the base station with help of Winprop.
Key Words:Mobile telephone system, Cell cluster, Frequency re-use, Network performance, Power,Winprop.
This document introduces the exponential Pareto distribution (EPD), a new probability distribution derived from the exponential and Pareto distributions. Some key properties of the EPD are derived, including its probability density function, cumulative distribution function, moments, coefficients of variation, skewness and kurtosis. Parameter estimation for the EPD is also discussed using maximum likelihood estimation. Plots of the density, distribution, and other functions of the EPD are provided for various parameter values.
A simple, easy and flexible Defected Ground Structure (DGS) is proposed for rectangular arrays and
demonstrated theoretically in here with the aim of achieving suppression of cross polarization resulting improved
polarization purity in radiated fields. The employed DGS appears to be highly efficient in terms of suppressing
Cross Polarization especially in H-plane. A [2×2] array has been designed having aspect ratio of 1.3 and showing
14 dB enhancement in the segregation between the co-polarization to cross-polarization dissemination with
improved impedance Bandwidth.
It is a algorithm used to find a minimum cost spanning tree for connected weighted undirected graph.This algorithm first appeared in Proceedings of the American Mathematical Society in 1956, and was written by Joseph Kruskal.
The document describes the design of a cross dipole antenna for GPS applications operating at 2 GHz. The antenna consists of two orthogonal dipole elements that are fed 90 degrees out of phase to provide circular polarization. The designed antenna resonates at 2 GHz with a 500 MHz bandwidth and meets requirements of VSWR <= 3 and return loss <= -10 dB. Simulation results using HFSS software show the antenna provides circular polarization reception in the GPS band as desired.
Kruskal's algorithm is a minimum spanning tree algorithm that finds the minimum cost collection of edges that connect all vertices in a connected, undirected graph. It works by sorting the edges by weight and then sequentially adding the shortest edge that does not create a cycle. The algorithm uses a disjoint set data structure to track connected components in the graph. It runs in O(ElogE) time, where E is the number of edges.
This document discusses techniques for suppressing grating lobes in distributed subarray (DSA) antennas. It describes how grating lobes, which are unintended beams that limit system performance, are produced by the large spacing between subarrays in a DSA. The principle of pattern multiplication is introduced as a technique for reducing grating lobes by designing the transmit and receive array patterns such that nulls in one pattern coincide with grating lobes in the other pattern. Simulation results showing the grating lobe and null locations for sample transmit and receive arrays are presented, demonstrating that pattern multiplication can effectively suppress grating lobes in the combined two-way pattern.
This document summarizes a research paper on the design and development of a complementary symmetry rectangular microstrip antenna for triple wideband operation. The antenna has dimensions of 80 x 50 x 1.6 mm3 and operates between 3.96-11.56 GHz with a maximum bandwidth of 29.45%. It is fabricated on a low-cost glass epoxy substrate using a simple photolithography process. Experimental results show that the antenna achieves triple wideband operation through the use of complementary E-slots on the patch and an H-slot on the ground plane. The antenna exhibits broadside radiation characteristics with a peak gain of 2.64 dB, making it suitable for applications in C and X-band communication systems.
The document discusses minimum spanning trees (MST) and two algorithms for finding them: Prim's algorithm and Kruskal's algorithm. It begins by defining an MST as a spanning tree (connected acyclic graph containing all vertices) with minimum total edge weight. Prim's algorithm grows a single tree by repeatedly adding the minimum weight edge connecting the growing tree to another vertex. Kruskal's algorithm grows a forest by repeatedly merging two components via the minimum weight edge connecting them. Both algorithms produce optimal MSTs by adding only "safe" edges that cannot be part of a cycle.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
ABRA: Approximating Betweenness Centrality in Static and Dynamic Graphs with ...Kaushalya Madhawa
Paper presentation on ABRA: a random sampling based approximate betweenness centrality estimation method
Please find the PDF here https://drive.google.com/open?id=0BwND8Ws5fgEeTlVBejFGLW9QaFU
This document contains notes on graphing trigonometric functions. It reviews the domains, ranges, periods, maximums, minimums, and intercepts of y=sin(x), y=cos(x), and y=tan(x). It explains that compressing or stretching the period of these functions is achieved by including a coefficient b in front of x, such as y=sin(bx). Examples are provided and homework assignments are listed at the end.
This document provides a summary of a lecture on multipath fading channels for mobile communication systems. It discusses various topics related to multipath fading including shadowing (slow fading), fast fading channels, mathematical models, and probability models. Specific topics covered include the lognormal distribution of shadowing, the two ray model, modeling the wireless channel as a black box, an introduction to fast fading, and Doppler shift. References several papers on topics like fading channels, narrowband land mobile channels, and the WSSUS channel model.
1) The document discusses digital transmission of analog signals using techniques like Pulse Code Modulation (PCM), Differential Pulse Code Modulation (DPCM), and Delta Modulation (DM).
2) PCM involves sampling the analog signal, quantizing the sample amplitudes, and encoding the quantized values into binary codewords.
3) Nyquist sampling theorem states that if a signal is bandlimited to W Hz, it can be reconstructed perfectly from samples taken at a rate of at least 2W samples/second.
This document analyzes the performance of adaptive algorithms in future cellular networks using MATLAB. It discusses important cellular network parameters like cell size, number of users, co-channel reuse ratio, path loss, transmitted power, signal-to-noise ratio, bit error rate, modulation technique (QAM), frequency reuse, and relay response. It presents MATLAB programs and results that model hexagonal cell layout, co-channel reuse ratio, path loss effects, response of signal-to-interference-plus-noise ratio, and average spectral efficiency as key parameters are varied. The analysis concludes the adaptive algorithm concept and MATLAB simulations would help cellular network designers optimize performance and identify issues cost-effectively before implementation.
The document discusses enhancements to the generalized sidelobe canceller (GSC) algorithm for audio beamforming. It presents:
1) Amplitude scaling models to account for near-field effects, including a 1/r model, acoustic physics model, and statistical model. Experimental results found the acoustic physics model provided a small improvement.
2) Automatic target alignment using cross-correlation and a threshold, but experimental results found this did not improve performance over the standard GSC due to low signal-to-noise ratios.
3) Analysis of different array geometries using beamfield plots and simulations, finding array geometry has the largest impact on performance and random arrays have potential if well described.
Massive MIMO for Cooperative Network ApplicationVARUN KUMAR
This document summarizes a research paper on analyzing the achievable rate and power efficiency of massive MIMO in cooperative networks using zero-forcing receivers. It outlines the problem definition, system model, and simulation results. The system model considers uplink transmission from mobile users to a base station via relay stations. It analyzes the observed signal-to-noise ratio in direct and cooperative transmission and defines achievable rate metrics for direct, non-cooperative, and cooperative decoding schemes. Power efficiency is defined as the achievable rate divided by the total transmit power of all nodes.
Solucionario Beer, Johnton, Mazurek y Eisenberg - Octava Edicion.pdfAntonellaMeaurio
The document discusses a blog that provides university textbooks and solutions manuals for free download. It states that the solutions manuals contain step-by-step solutions to all the problems in the textbooks. It invites the reader to visit the site to download the files for free.
Blind separation of complex-valued satellite-AIS data for marine surveillance...IJECEIAES
In this paper, the problem of the blind separation of complex-valued Satellite-AIS data for marine surveillance is addressed. Due to the specific properties of the sources under consideration: they are cyclo-stationary signals with two close cyclic frequencies, we opt for spatial quadratic time-frequency domain methods. The use of an additional diversity, the time delay, is aimed at making it possible to undo the mixing of signals at the multi-sensor receiver. The suggested method involves three main stages. First, the spatial generalized mean Ambiguity function of the observations across the array is constructed. Second, in the Ambiguity plane, Delay-Doppler regions of high magnitude are determined and Delay-Doppler points of peaky values are selected. Third, the mixing matrix is estimated from these Delay-Doppler regions using our proposed non-unitary joint zero-(block) diagonalization algorithms as to perform separation.
Evaluation of channel estimation combined with ICI self-cancellation scheme i...ijcsse
Orthogonal Frequency Division Multiplexing (OFDM) is a modulation scheme, which is used in several wireless systems for transferring data at high rate. The multi path fading channel and the frequency offset between the transmitted and received carrier frequencies introduce ICI (Inter Carrier Interference). ICI effects the OFDM symbols and degrades the system performance. This paper proposes a solution: combine channel estimation and ICI self-cancellation to combat against ICI in doubly selective fading channel. The simulation results show the effect of this solution
Searching for aftershocks of underground explosions with cross correlationIvan Kitov
1) The document describes using cross-correlation techniques to analyze seismic data from underground nuclear explosions in North Korea.
2) Cross-correlation was able to identify signals in the 2006 North Korean test that were below the detection threshold, demonstrating this technique's ability to detect smaller events.
3) An analysis of seismic data from sensors in the five days following North Korea's 2009 underground nuclear test found no aftershocks above magnitude 3.0, consistent with the lack of detected radionuclides from smaller explosions.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document discusses green communication and summarizes several research papers on the topic. It outlines the objectives of green communication as protecting the environment from harmful EM radiation, reducing greenhouse gases, and reducing wireless network operational costs. It then summarizes several papers on topics like power control, resource allocation, power allocation, and massive MIMO. The document also discusses energy consumption in the ICT industry, wireless resource trading challenges, and open research areas in green communication like massive MIMO and cooperative communication. It presents two case studies analyzing the energy efficiency of massive MIMO systems with considerations for aspects like channel gain, number of antennas, and transceiver power consumption.
This document contains an analysis of eye diagrams and the Q-function for digital communication. It includes:
1) An explanation of how eye diagrams are generated and their purpose in analyzing communication systems. Eye diagrams provide an evaluation of signal-to-noise ratio, jitter, and other factors.
2) Code to generate eye diagrams using different bandwidths and an analysis of how bandwidth affects eye opening.
3) An explanation of the Q-function and its relationship to the normal probability density function, representing the probability of a value being above a threshold.
4) Scripts to plot the Q-function and illustrate its application in calculating bit error probability for digital transmission systems.
ENERGY EFFICIENCY OF MIMO COOPERATIVE NETWORKS WITH ENERGY HARVESTING SENSOR ...ijasuc
This paper addresses the maximizing network lifetime problem in wireless sensor networks (WSNs) taking
into account the total Symbol Error rate (SER) at destination. Therefore, efficient power management is
needed for extend network lifetime. Our approach consists to provide the optimal transmission power
using the orthogonal multiple access channels between each sensor. In order to deeply study the
properties of our approach, firstly, the simple case is considered; the information sensed by the source
node passes by a single relay before reaching the destination node. Secondly, global case is studied; the
information passes by several relays. We consider, in the previous both cases, that the batteries are nonrechargeable. Thirdly, we spread our work the case where the batteries are rechargeable with unlimited
storage capacity. In all three cases, we suppose that Maximum Ratio Combining (MRC) is used as a
detector, and Amplify and Forward (AF) as a relaying strategy. Simulation results show the viability of
our approach which the network lifetime is extended of more than 70.72%when the batteries are non
rechargeable and 100.51% when the batteries are rechargeable in comparison with other traditional
method.
ENERGY EFFICIENCY OF MIMO COOPERATIVE NETWORKS WITH ENERGY HARVESTING SENSOR ...ijasuc
This paper addresses the maximizing network lifetime problem in wireless sensor networks (WSNs) taking
into account the total Symbol Error rate (SER) at destination. Therefore, efficient power management is
needed for extend network lifetime. Our approach consists to provide the optimal transmission power
using the orthogonal multiple access channels between each sensor. In order to deeply study the
properties of our approach, firstly, the simple case is considered; the information sensed by the source
node passes by a single relay before reaching the destination node. Secondly, global case is studied; the
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rechargeable and 100.51% when the batteries are rechargeable in comparison with other traditional
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Wireless Vehicular Networks in Emergencies: A Single Frequency Network Approach
1. Wireless Vehicular Networks in
Emergencies:
A Single Frequency Network Approach
Andrea Tassi - a.tassi@bristol.ac.uk
Malcolm Egan - Université Blaise Pascal, Clermont-Ferrand, FR
Robert J. Piechocki and Andrew Nix - University of Bristol, Bristol, UK
Da Nang, Vietnam, 9th
January 2017
University of Bristol
Communication Systems and Network Group
SigTelCom 2017
2. I n d e x
1. LTE-A and the Single Frequency Network Infrastructure
2. The eMBMS Framework for Vehicular Emergencies
3. Performance Modeling and Design Optimisation
4. Numerical Results
5. Conclusions
Andrea Tassi - a.tassi@bristol.ac.uk
3. 1. LTE-A and the Single Frequency Network
Infrastructure
Andrea Tassi - a.tassi@bristol.ac.uk
4. S t a n d a rd LT E - A S F N I n f r a s t r u c t u re
Andrea Tassi - a.tassi@bristol.ac.uk
BS
BS
BS
BS
M1/M2
(MCE / MBMS-GW)
SFN
4
1
2
3
UE3
UEUUE2
UE1
UE4
LTE-A Core Network
• Multiple neighboring BSs (forming the SFN) transmit the same Point-to-
Multipoint (PtM) data streams in a synchronous fashion.
• This transmission mode has become increasingly common in 4G systems,
where it is also known as the SFN-eMBMS.
• SFNs have already proved effective in vehicular communication systems.
Multicell
Coordination
Entity (MCE)
5. 2. The eMBMS Framework for Vehicular
Emergencies
Andrea Tassi - a.tassi@bristol.ac.uk
6. P ro b l e m M o t i v a t i o n
Andrea Tassi - a.tassi@bristol.ac.uk
• The IEEE 802.11p/DSRC can achieve at most ~27 Mbps, in practice it is
hard to observe that.
• However, DSRC standards are suitable for low-rate data services (for e.g.,
positioning beacon, emergency stop messages, etc.).
• On the other hand, future CAVs will require solutions ensuring megabit-
per-second communication links to achieve proper ‘look-ahed’ services
(involving cameras, LIDARS, etc.), etc.
• The LTE-A infrastructure is already deployed in our cities.
7. O u r P ro p o s a l
Andrea Tassi - a.tassi@bristol.ac.uk
• Municipality-owned SFN that provides emergency coverage to a small area
of a city.
• The SFN serves a target cluster of vehicles to ensure that each vehicle can
reliably receive information to support improve road safety.
• Each base station (possibly battery-powered) in the SFN is equipped with
an antenna array with a highly directional beam. We assume that the
beamwidth of the main lobe is only sufficient to cover the target cluster.
• The SFN operates on the same frequency of an operator-owned network.
8. O u r P ro p o s a l
Andrea Tassi - a.tassi@bristol.ac.uk
Major safety hazard
Center of the
target cluster
Interfering
Base Station
SFN Base Station
• Vehicles and interfering base stations are equipped with isotropic antennas.
• Each vehicle provides its location to the SFN controller via the nearest base
station. The SFN controller can estimate the center of the target cluster.
10. B S D i s t r i b u t i o n
Andrea Tassi - a.tassi@bristol.ac.uk
• Positions of interfering BS positions
follow a 2D PPP
• Interfering BSs can be in LOS (with
prob. pL) or NLOS (with prob. pN)
with the center of the cluster.
• SFN base stations assumed in LOS
with the center of the cluster
x-coordinate ·10−3
y-coordinate·10−3
−2 −1.5 −1 −0.5 0 0.5 1 1.5 2
−2
−1.5
−1
−0.5
0
0.5
1
1.5
2
Interfering BS
SFN BS
Center of the
Target Cluster
11. T h e P ro b a b i l i t y F r a m e w o r k
Andrea Tassi - a.tassi@bristol.ac.uk
• We define the SINR at the center of the cluster as
hj ~ EXP(1)
PL,
thermal noise
power
• We characterize the SINR outage as follows
SINRO =
GS,TX GRX
MX
i=1
Pi hi `(S)
(dS,i)
W + GI,TX GRX PI
X
j2
hj `(I)
(dI,i)
d ↵
PT(✓) = P [SINRO < ✓] = P
" MX
i=1
Pi hi d ↵L
S,i > ✓
W + I
GS,TX GRX
#
Inst. TX pow.
12. S I N R O u t a g e P ro b a b i l i t y
Andrea Tassi - a.tassi@bristol.ac.uk
• are indep. exponentially distributed RV with mean
PT(✓) = P [SINRO < ✓] = P
" MX
i=1
Pi hi d ↵L
S,i > ✓
W + I
GS,TX GRX
#
{Pi hi d ↵S
S,i }M
i=1
µi = Pi d ↵S
S,i
• The cumulative distribution function of a sum of exponentially distributed
random variables is [*]:
F(z) =
aY
j=1
µ ok
j
aX
k=1
okX
`=1
µok `
k
k,` µ 1
k zok `
e z/µk
(ok `)!(` 1)!
.
[*] S. Amari and R. Misra, “Closed-Form Expressions for Distribution of Sum of Exponential
Random Variables,” IEEE Trans. Rel., vol. 46, no. 4, pp. 519–522, Dec. 1997.
13. S I N R O u t a g e P ro b a b i l i t y
Andrea Tassi - a.tassi@bristol.ac.uk
• The cumulative distribution function of a sum of exponentially distributed
random variables is:
F(z) =
aY
j=1
µ ok
j
aX
k=1
okX
`=1
µok `
k
k,` µ 1
k zok `
e z/µk
(ok `)!(` 1)!
.
k,` (t) =
@` 1
@t` 1
8
<
:
1
t
aY
j=1,j6=k
✓
1
µj
+ t
◆ oj
9
=
;
⌦k,` (t) = ( 1)ok ` @ok `
@xok `
(
e
µ
1
k
✓W
GS,TX GRX
x
LI
✓
µ 1
k ✓I
GS,TX GRX
x
◆ )
x=1
.
often these
terms refers to
“0-derivatives”
14. S I N R O u t a g e P ro b a b i l i t y
Andrea Tassi - a.tassi@bristol.ac.uk
PT(✓) = P [SINRO < ✓] = P
" MX
i=1
Pi hi d ↵L
S,i > ✓
W + I
GS,TX GRX
#
PT(✓) = EI
F
✓
✓
W + I
GS,TX GRX
◆
(a)
=
aY
j=1
µ ok
j
aX
k=1
okX
`=1
µok `
k
k,` µ 1
k
(ok `)!(` 1)!
·
µok `
k EI0
⇥
Uok `
e U
⇤
U µ 1
k ✓ W+I
GS,TX GRX
15. S I N R O u t a g e a n d R a t e C o v e r a g e P ro b .
Andrea Tassi - a.tassi@bristol.ac.uk
• … after some manipulations we optain:
PT(✓) =
aY
j=1
µ ok
j
aX
k=1
okX
`=1
µok `
k
k,` µ 1
k ⌦k,` µ 1
k
(ok `)!(` 1)!
,
• From above we define the rate coverage probability as
RC() = P[ log2(1 + ·SINRO) > ] = P
⇥
SINRO > 2
1
⇤
system BW
16. P o w e r A l l o c a t i o n M o d e l
(PA) min
P1,...,PM
MX
i=1
Pi (1)
subject to PT(ˆ✓) ˆT (2)
0 Pi ˆP i = 1, . . . , M. (3)
• The sum of the TX pow. is minimised.
• Eq. (2) provides a QoS constraint, while Eq. (3) is a design constraint
• Easily solvable by means of a water-filling strategy. For further details please
refer to A. Tassi, I. Chatzigeorgiou and D. Vukobratović, "Resource-
Allocation Frameworks for Network-Coded Layered Multimedia
Multicast Services," in IEEE Journal on Selected Areas in
Communications, vol. 33, no. 2, pp. 141-155, Feb. 2015. Andrea Tassi - a.tassi@bristol.ac.uk
18. C o n s i d e re d S c e n a r i o
Andrea Tassi - a.tassi@bristol.ac.uk
• Simulated scenario with radius
equal to 1E3 m
• System BW equal to 50 MHz
• TX pow. of the interfering BSs equal
to 10 W
• Max. TX pow. of an SFN BS set
equal to 30 W
x-coordinate ·10−3
y-coordinate·10−3
−2 −1.5 −1 −0.5 0 0.5 1 1.5 2
−2
−1.5
−1
−0.5
0
0.5
1
1.5
2
Interfering BS
SFN BS
Center of the
Target Cluster
19. S I N R O u t a g e P ro b a b i l i t y
Andrea Tassi - a.tassi@bristol.ac.uk
θ (dB)
PT(θ)
6.5 8.5 10.5 12.5 14.5 16.5 18.5 20.5 22.5 24.5 26.5 28.5 30.5
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
λBS = 0.1 · 10−5
λBS = 0.2 · 10−5
λBS = 0.3 · 10−5
Simulation
Theory
20. S I N R O u t a g e P ro b a b i l i t y
Andrea Tassi - a.tassi@bristol.ac.uk
λBS · 105
PT
0.1 0.2 0.3 0.4 0.5 0.6
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
θ = 10.3 dB
θ = 15.3 dB
θ = 20.3 dB
θ = 25.3 dB
Simulation
Theory
21. PA M o d e l
Andrea Tassi - a.tassi@bristol.ac.uk
ˆθ (dB)
M
i=1P∗
i(W)
6.5 8.5 10.5 12.5 14.5 16.5 18.5 20.5
0
10
20
30
40
50
60
λBS = 0.1 · 10−5
λBS = 0.2 · 10−5
λBS = 0.3 · 10−5
λBS = 0.4 · 10−5
λBS = 0.5 · 10−5
λBS = 0.6 · 10−5
22. PA M o d e l
Andrea Tassi - a.tassi@bristol.ac.uk
λBS · 105
M
i=1P∗
i(W)
0.1 0.2 0.3 0.4 0.5 0.6
0
10
20
30
40
50
60
ˆθ = 6.3 dB
ˆθ = 8.3 dB
ˆθ = 10.3 dB
ˆθ = 12.3 dB
ˆθ = 14.3 dB
24. F i n a l R e m a r k s
• We characterised the performance of a SFN suitable for vehicular
emergencies
• We obtained performance guarantees of SFNs in terms of bounds on
outage probabilities using techniques from stochastic geometry.
• These bounds form a basis for optimizing the power allocation of each
base station in the SFN, which is important when these base stations rely
on off-grid power sources.
• In the considered scenarios, we have shown that the proposed PA model
can ensure and overall transmission power footprint that: (i) can be up to
20 times smaller than a static PA solution, and (ii) meets target SINR outage
constraints. Andrea Tassi - a.tassi@bristol.ac.uk
25. Wireless Vehicular Networks in
Emergencies:
A Single Frequency Network Approach
Andrea Tassi - a.tassi@bristol.ac.uk
Malcolm Egan - Université Blaise Pascal, Clermont-Ferrand, FR
Robert J. Piechocki and Andrew Nix - University of Bristol, Bristol, UK
Da Nang, Vietnam, 9th
January 2017
University of Bristol
Communication Systems and Network Group
SigTelCom 2017
Thanks for your attention!