Cellular Communications

Clarification: The term "Parasites" in this framework refers to parasitic-like disruption of cellular communication networks, encompassing actual parasites, chronic pathogens, toxins, and inflammatory processes that systematically undermine the three pillars of cellular coherence: gap junction communication, bioelectric coordination, and circadian synchronization. The mathematical framework and therapeutic protocols apply universally to any decoherence-inducing mechanism.

The performance of linear precoding schemes in downlink Massive MIMO systems is dealt with in this paper. Linear precoding schemes are incorporated with zero-forcing (ZF) and maximum ratio transmission (MRT), truncated polynomial expansion (TPE), regularized zero force (RZF) in Downlink massive MIMO systems. Massive MIMO downlink output is evaluated with linear precoding included. This paper expresses the performance of achievable sum-rate linear precoding with variable signal-to-noise (SNR) ratio and achievable sum rate and several transmitter-receiver antennas, such as imperfect CSI, less complex processing, and inter-user interference. The transmitter has complete state information on the channel. The information narrates how a signal propagates to the receiver from the transmitter and reflects, for example, the cumulative effect of distance scattering, fading, and power decay. They show that the performance analysis of two linear precoding techniques, i.e., Maximum Ratio Transmission (MRT) and Zero Forcing (ZF) for downlink mMIMO output network over a perfect chain. The results show the improved ZF precoding achievable sum rate compared to the MRT precoding schemes and compared the average achievable rate RZF and TPE. Index Terms-massive MIMO (mMIMO), precoding, zero-forcing, matched filter, truncated polynomial expansion, regularized zero-forcing, average achievable rate.

Search and Rescue (US&R) NY-TF1 In order to gather data in support of standards development for urban search and rescue robots, NIST is conducting a series of field tests to quantify the functionality and performance of various candidate robots. During these tests, manufacturers bring robots that may be appropriate for various urban search and rescue applications, and emergency responders put the robots through NIST-derived tests designed to measure their performance in key areas. During a set of field tests at the Montgomery County Fire Academy in Maryland in August 2006, members of the Electromagnetics Division and Intelligent Systems Division of NIST developed and carried out a uniform series of spectral analysis tests on each of the robots that participated in the event. We report here on results of this initial set of field tests of the wireless link.

The 5 th generation of cellular networks (5G) will provide high speed and high-availability wireless links for communication between mobile users. The usage of aerial platforms as base stations has been recently proposed to meet the above requirements, especially in densely-packed urban areas. To make an accurate prediction of the performance in such a communication system the availability of suitable channel models is a fundamental requirement. Here, we concentrate on a simple path loss and shadow fading channel model that is commonly used to describe the propagation between an aerial base station and a user on the ground. A commercial 3D raytracing simulator is used to extract the main parameters used in the model and the Line of Sight/Non Line of Sight probabilities as a function of the transmitter height and elevation angle. We consider three reference scenarios: Suburban, Urban and Urban High Rise generated according to ITU-R specifications. As a novel contribution, we also show simulation results for the spatial correlation of the received signal in the three considered scenarios.

Understanding cell-cell communication (CCC) pathw a y s from single-cell or spatial transcriptomic data is k e y to unra v eling biological processes. Recently, multiple CCC methods have been developed but primarily focus on refining ligand-receptor (L-R) interaction scores. A critical gap for a more comprehensive picture of cellular crosstalks lies in the integration of upstream and downstream intracellular pathways in the sender and receiver cells. We report here CausalCCC, https:// miic.curie.fr/ causalCCC.php , an interactive web server, which addresses this need by reconstructing gene-gene interaction pathw a y s across tw o or more interacting cell types from single-cell or spatial transcriptomic data. CausalCCC includes a graphical introduction and a demo dataset within the workbench page as well as a comprehensive tutorial. CausalCCC methodology integrates a robust and scalable causal network reconstruction method, multivariate information-based inductive causation, with internally computed L-R pairs using LIANA+ (including CellphoneDBv5, SingleCellSignalR, Connectome, NATMI, and Log2FC). Alternatively, user-defined L-R pairs from any CCC methods can also be uploaded. We sho w case here CausalCCC on different single-cell and spatial transcriptomic datasets from three original CCC methods (NicheNet, CellChat, and Misty). CausalCCC w eb serv er offers unique interactive visualization tools dedicated to single-cell data practitioners seeking to go be y ond L-R scores and explore extended CCC pathways across multiple interacting cell types.

For a cellular communication network, the loss in up-link bandwidth-efficiency resulting from power equalization is considered. Here power equalization refers to the operation of adjusting the transmit power of mobile units in such a way that the received power is the same for all units whereas bandwidth-efficiency is measured in terms of sum-rate per cell divided by the total system bandwidth. A single-cell system is considered first, and the bandwidth efficiency is determined with and without power equalization as well as with and without shadowing. The analysis is then extended to multi-cell-systems. It is found that in all cases power equalization severely penalizes the bandwidth-efficiency.

El uso de telecomunicaciones en diferentes aplicaciones del sector eléctrico, ha permitido verificar la evolución de su arquitectura, ya sea por tecnologías alámbricas o inalámbricas. El servicio prestado por cada una de las dos opciones no permiten el uso de una sola tendencia y en la actualidad se torna inminente el uso de soluciones híbridas, donde cohabitan varias tecnologías para cada etapa de una red inteligente. De igual manera los planes de negocios para implementar la infraestructura de medición inteligente requieren de diferentes soluciones tecnológicas; operadoras de red y fabricantes, siendo necesaria una gestión de las redes de elecomunicaciones para este tipo de servicio específico y que facilitan la creación de herramientas para la optimización del consumo de la energía eléctrica,incorporando nuevos servicios al consumidor - cliente, en relación a los que actualmente ofrece una empresa de distribución.

The success of cellular communications networks shows the interest of users in mobility. Host mobility support in IP networks is a first step in the adaptation of these networks to the needs of users in this field. But, there exists also the need of supporting the movement of a complete network that changes its point of attachment to the fixed infrastructure. This paper describes the architecture designed in the EU DAIDALOS II project to provide Internet access through moving networks. The designed moving networks architecture support the following main features: Route Optimisation, Multicast traffic delivery, security and authentication integration, end-to-end QoS and interaction with Localised Mobility Management solutions.

In the process of the transmission system, the signal is passed to a medium or channel to send the information from the transmitter to the receiver. In the communication system by using the channel, the information transmitted signal may experience interference (noise) which resulted an errors at the receiver side. To suppress the influence of noise, it can be used equalizer at the receiver side. Equalizer used in this design was the adaptive equalizer. The adaptive equalizer was the equalizer that automatically adjusted to the characteristics of the channel that always changing over time. This research designed a transmission system using Flat Fading channel with Phase Shift Keying modulation M-array (M-PSK), which was used in the receiver adaptive equalizer linier using Least Mean Square Algorithm (LMS). The test results of the BER performance of M-PSK transmission systems before and after using the equalizer in the range of Eb/No 0 of Up 40 dB showed improved system performance b...

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Abstrak Perkembangan teknologi informasi di era sekarang berkembang sangat pesat dikarenakan telah berubahnya seluruh informasi analog menjadi informasi digital, dan dengan berubahnya sistem analog ke sistem digital seluruh teknologi sangat memudahkan pengguna untuk mengaplikasikan teknologi tersebut karena sistem digital mempunyai banyak kelebihan dibandingankan sistem analog. Akan tetapi, dengan semakin canggihnya perubahan sistem informasi dan teknologi, akan ada kanal yang dilewati oleh sebuah sistem komunikasi. Kanal AWGN dan kanal Rayleigh adalah jenis kanal yang akan mempengaruhi proses modulasi yang ada. Selama ini belum ada simulator yang dapat memudahkan sistem pembelajaran pada mata kuliah sistem komunikasi sehingga menyebabkan kesulitan untuk dapat mempelajari banyak tentang ilmu yang ada di dalam sistem komunikasi terutama pada modulasi Quadrature Ampitude Modulation. Pada tugas akhir ini digunakan software matlab sebagai penunjang untuk melihat sebagaimana besar pengar...

Channel coding berfungsi untuk menjaga informasi atau data digital dari error yang mungkin terjadi selama proses transmisi dengan cara menambahkan bit redundansi (tambahan) ke dalam data yang akan dikirimkan. Pada penelitian ini, dilakukan simulasi dan analisa terhadap performansi teknik channel coding dan decoding menggunakan convolutional code dan algoritma viterbi pada kanal dengan AWGN (Additive White Gaussian Noise) menggunakan bahasa pemograman Matlab 7.1 serta menggunakan modulasi QPSK. Dalam simulasi diperoleh hasil perbandingan performansi antara sistem tanpa menggunakan channel coding dan decoding dengan sistem yang menggunakan teknik channel coding (convolutional code) dan decoding (algoritma viterbi). Hasil simulasi ditampilkan dalam bentuk grafik SNR (Signal to Noise Ratio) terhadap BER (Bit Error Rate). Standar BER yang digunakan adalah standar minimum untuk transmisi suara yaitu 10-3. Pada komunikasi tanpa covolutional code dan algoritma viterbi, sistem tidak dapat me...

ABSTRAK Teknologi Orthogonal Frequency Division Multiple Access (OFDMA) merupakan teknik akses jamak yang digunakan pada Long Term Evolution (LTE) kanal downlink . OFDMA memiliki suatu blok transmisi yang dinamakan dengan  resoure block, yang akan dialoksasikan kepada user . Diperlukannya skema pengalokasian daya resource block agar tiap resource block dapat bekerja secara optimal, sebagai contohnya skema alokasi daya waterfilling . Skema alokasi daya waterfilling mengalokasikan daya berdasarkan kondisi dari user , dimana user yang memiliki noise tinggi akan dialokasikan daya lebih tinggi dibandingkan dengan user yang memiliki nilai noise yang lebih rendah. Penelitian ini dilakukan secara simulasi dengan Matlab yang bertujuan untuk mengetahui pengaruh penggunaan skema alokasi daya waterfilling dibandingkan dengan skema equal power allocation (EPA) sebagai skema pengalokasian daya transmisi resource block. Parameter kinerja berdasarkan nilai BER data rate dan fairness . Hasil penelit...

Orthogonal Frequency Division Multiple Access (OFDMA) technology is a plural access technique used in the Long Term Evolution (LTE) downlink channel. OFDMA has a transmission block called resoure block, which will be assigned to the user. A scheme to allocate resource block power is needed so that each resource block can work optimally, for example the waterfilling power allocation scheme. The waterfilling power allocation scheme allocates power based on the condition of the user, users who have bad channel condition will be allocated higher power compared to users who have greatter channel condition. This research was conducted in simulation with Matlab which aims to determine the effect of using the waterfilling power allocation scheme compared to the equal power allocation (EPA) scheme as a scheme for allocating the power of resource block transmission. The usage performance analysis of the waterfilling power allocation scheme as a resource block power allocation scheme for OFDMA uses parameters from the BER value, data rate, and fairness. After doing the simulation, it was found that the use of the waterfilling power allocation scheme can increase the system fairness value and system BER compared to using the equal power allocation scheme but has a lower average data rate of user value. The use of waterfilling power allocation scheme has an increase in the system fairness value of an average of 16.625%. The average data rate value of the user using the waterfilling power allocation scheme decreases the value of 0.7081 Mbps. In the BER parameter, the system BER value using the waterfilling power allocation scheme is better in all scenarios compared to the equal power allocation scheme.

The success of cellular communications networks shows the interest of users in mobility. Host mobility support in IP networks is a first step in the adaptation of these networks to the needs of users in this field. But, there exists also the need of supporting the movement of a complete network that changes its point of attachment to the fixed infrastructure. This paper describes the architecture designed in the EU DAIDALOS II project to provide Internet access through moving networks. The designed moving networks architecture support the following main features: Route Optimisation, Multicast traffic delivery, security and authentication integration, end-to-end QoS and interaction with Localised Mobility Management solutions.

This study explores the construct validity of intrinsic sources of personal relevance (ISPR), an intra-individual source of (felt) involvement. Data relative to the internal consistency and the convergent, discriminant, and nomological validity of ISPR were generated in an experiment and tested using a structural equation methodology. Measures of ISPR were shown to achieve internal consistency and convergent validity, as well as discriminant validity with respect to measures of subjects' domain knowledge. Evidence for the nomological validity of ISPR was obtained by examining the relationships between three theoretically related constructs-ISPR, domain knowledge, and felt involvement.

Spektrum frekuensi pada jaringan komunikasi nirkabel bersifat terbatas. Oleh karena itu diperlukan solusi dalam mengoptimalkan penggunaan spektrum frekuensi, salah satunya adalah dengan penggunaan jaringan radio kognitif. Spektrum pada jaringan radio kognitif bersifat heterogen, yaitu terdiri dari Primary User (PU) dan Secondary User (SU). Pada jaringan radio kognitif, SU dapat menggunakan kanal yang sama dengan PU selama SU tidak menyebabkan interferensi yang dapat menurunkan unjuk kerja dari PU. Salah satu metode yang dapat digunakan untuk meminimalkan interferensi adalah dengan metode pemilihan kanal menggunakan pendekatan game theory. Dengan metode ini, interferensi SU terhadap PU dapat diminimalkan. Pada penelitian ini, dianalisis kinerja dari metode pemilihan kanal menggunakan pendekatan game theory. Unjuk kerja jaringan radio kogntif dapat ditingkatkan dengan dengan menggunakan pemilihan kanal dengan pendekatan game theory. Pada jaringan radio kognitif tanpa keberadaan PU, ni...

This thesis project allows us to analyze the behavior of the telecommunications network in urban areas; and thus warn the needed Medidores Volumen 20 bytes/M Volumen 40 bytes/M Volumen 60 bytes/M Volumen 80 bytes/M Volumen 100 bytes/M Volumen 120 bytes/M Volumen 140 bytes/M Volumen 160 bytes/M Volumen 180 bytes/M

frequencies between 100 GHz and 300 GHz are being considered as a key enabler for the sixthgeneration (6G) wireless communications due to the vast amounts of unused spectrum. The 3rd Generation Partnership Project (3GPP) included the indoor industrial environments as a scenario of interest since Release 15. This paper presents recent sub-THz channel measurements using directional horn antennas of 27 dBi gain at 142 GHz in a factory building, which hosts equipment manufacturing startups. Directional measurements with copolarized and cross-polarized antenna configurations were conducted over distances from 6 to 40 meters. Omnidirectional and directional path loss with two antenna polarization configurations produce the gross cross-polarization discrimination (XPD) with a mean of 27.7 dB, which suggests that dual-polarized antenna arrays can provide good multiplexing gain for sub-THz wireless systems. The measured power delay profile and power angular spectrum show the maximum root mean square (RMS) delay spread of 66.0 nanoseconds and the maximum RMS angular spread of 103.7 degrees using a 30 dB threshold, indicating the factory scenario is a rich-scattering environment due to a massive number of metal structures and objects. This work will facilitate emerging sub-THz applications such as super-resolution sensing and positioning for future smart factories.

This paper demonstrates how spectrum up to 1 THz will support mobile communications beyond 5G in the coming decades. Results of rooftop surrogate satellite/tower base station measurements at 140 GHz show the natural isolation between terrestrial networks and surrogate satellite systems, as well as between terrestrial mobile users and co-channel fixed backhaul links. These first-of-their-kind measurements and accompanying analysis show that by keeping the energy radiated by terrestrial emitters on the horizon (e.g., elevation angles ≤ 15°), there will not likely be interference in the same or adjacent bands between passive satellite sensors and terrestrial terminals, or between mobile links and terrestrial backhaul links at frequencies above 100 GHz.

A new method for measuring the intensity of turbulence in the planetary boundary layer was investigated, and showed high correlation with measurements from weather radar. This method takes measurements of cell phone signal strength and uses scintillation in the signal to estimate the strength of local turbulence. Using cell phone signals provides unique measurement advantages: it is a passive measurement method, it is not strongly affected by precipitation, and one device can potentially measure several paths at once. The measurements were taken using an Android cell phone running a custom built application. Turbulence was quantified using the index of refraction structure constant, C 2 n , which is related to the amount of energy in the turbulence. The goal of the investigation was to determine if C 2 n values calculated from the cell phone signal power show a relationship to C 2 n measurements taken over the communication path. Based on the strength of the agreement between measurements made by the new method and those done with an established method, it is concluded that turbulence changes can be measured using cell phone signals. The correlation of C 2 n values measured using the two methods was calculated for 42 periods of about 12 hours each. Correlation varied over the 42 periods, but was high and statistically significant in most measurements. The mean absolute value of peak Pearson correlation was 0.5865 with a mean p-value of 0.0251. Standard deviations of these values are 0.2311 and 0.0264, respectively. The standard deviations are relatively high due to two outliers where the correlation was particularly low. This thesis presents the experimental work that was done, the results of the work, the author's interpretation of the results, and suggestions for continued research.

Outdoor-to-indoor (OtI) signal propagation further challenges link budgets at millimeter-wave (mmWave). To gain insight into OtI mmWave at 28 GHz, we conducted an extensive measurement campaign consisting of over 2,000 link measurements in West Harlem, New York City, covering seven highly diverse buildings. A path loss model constructed over all links shows an average of 30 dB excess loss over free space at distances beyond 50 m. We find the type of glass to be the dominant factor in OtI loss, with 20 dB observed difference between clustered scenarios with low-and high-loss glass. Other factors, such as difference in floor height, are found to have an impact between 5ś10 dB. We show that for urban buildings with high-loss glass, OtI data rates up to 400 Mb/s are supported for 90% of indoor users by a base station (BS) up to 49 m away. For buildings with low-loss glass, such as our case study covering multiple classrooms of a public school, data rates over 2.8/1.4 Gb/s are possible from a BS 68/175 m away when a line-of-sight path is available. We expect these results to be useful for the deployment of OtI mmWave networks in dense urban environments and the development of scheduling and beam management algorithms. CCS CONCEPTS • General and reference → Measurement; • Networks → Network measurement; Wireless access networks; Physical links.

In 2001, Oregon State University (OSU) in collaboration with the Oregon Department of Transportation and the Road User Fee Task Force (RUFTF) began investigating a Vehicle Miles Travelled (VMT) based alternative to the fuel tax. The culminating phase of this five year effort is the execution of a pilot test involving approximately 280 volunteer drivers. A specific VMT-based technology, referred to as the Pilot Test Technology Configuration (PTTC) will be used in the pilot test. This paper discusses the lessons learned in the design and development of the PTTC, especially the challenges faced with the use of RFID technology to identify and collect VMT data from equipped vehicles.

Белорусский государственный университет информатики и радиоэлектроники, Республика Беларусь Поступила в редакцию 8 октября 2017 Аннотация. Приведены результаты сравнения оценок средней интенсивности электромагнитного фона, создаваемого базовыми станциями сотовой связи, с использованием предложенной автором методики, с опубликованными результатами измерений уровней электромагнитного фона в различных странах. Эти данные подтверждают адекватность предложенной методики и ее практическую значимость для оценки электромагнитной экологии территорий и электромагнитной безопасности населения. Ключевые слова: сотовая связь, электромагнитная нагрузка, электромагнитный фон, электромагнитная экология, электромагнитная безопасность. Abstract. Results of comparison estimations of average intensity of the electromagnetic background created by base stations of cellular communications, performed with use of the technique offered by the author, with the published results of measurements of levels of an electromagnetic background in the various countries, are presented. This data confirms of adequacy of the offered technique and its practical importance for an estimation of electromagnetic ecology of different areas and electromagnetic safety of the population.

The beam management is a procedure that properly selects the beams to overcome strong path loss attenuation. This procedure is specially important in 5G-NR (new radio) deployments that operate in millimeter waves frequencies. We propose a novel beam tracking solution that is based on a reinforcement learning framework. More specifically, using the Q-learning algorithm, the user equipments learn over time the best set of beams to maximize their own signal-to-noise to interference ratio. Our framework takes into account reference signals in the 5G technical specification and propose a measurement protocol to implement the Q-learning. The proposed method shows better spectral efficiency than the beam sweeping technique for the multiuser MIMO case.

Penulisan ini difokuskan pada salah satu teknik FEC DVB-T, yaitu Outer Coding (Reed Solomon code) dengan simbol pesan sebanyak 188, code word 204 simbol, dan errorcorrection 8 simbol. Untuk simulasi digunakan bahasa Visual Basic 6.0 dengan tampilan pada setiap proses encoding dan decodingnya. Proses simulasi yang dibuat ini menggunakan data input urut 1-188 dan jumlah error yang dapat dikoreksi sampai

All the contents of this work, except where otherwise noted, is licensed under a Creative Commons Attribution 4.0 International license. Todo o conteúdo deste trabalho, exceto quando houver ressalva, é publicado sob a licença Creative Commons Atribição 4.0. Todo el contenido de esta obra, excepto donde se indique lo contrario, está bajo licencia de la licencia Creative Commons Reconocimento 4.0.

This article proposes the optimal resource allocation of radio channels available in cellular networks for the transmission of data from the smart meters to information management systems. The model designed identifies and counts the subscribers of the electricity sector in a geographical area; through the kmeans algorithm the cellular radio bases are located. The optimal location of radio bases provides communication to all devices within its coverage radius. The communication channels available for data transmission are optimized using the Greedy algorithm, which set the time when smart meters must send their data through the disused communication channels

All the contents of this work, except where otherwise noted, is licensed under a Creative Commons Attribution 4.0 International license. Todo o conteúdo deste trabalho, exceto quando houver ressalva, é publicado sob a licença Creative Commons Atribição 4.0. Todo el contenido de esta obra, excepto donde se indique lo contrario, está bajo licencia de la licencia Creative Commons Reconocimento 4.0.

The objective of this research is to gather data for an urban area, evaluate, and assess the applicability of vehicle miles traveled (VMT) fee to replace or complement the gas tax, and mitigate the local transportation finance deficit. Vehicle data collected from three geographically distributed service stations in Charlotte, North Carolina were used to evaluate multiple VMT fee scenarios. The results indicate that charging 0.625 cents per each mile traveled or 1.00 cent per additional mile exceeding 5,000 miles per year, to complement the gas tax, could generate enough revenue to mitigate the transportation finance deficit estimated equal to $30 M to $35 M at the time of this research for the city of Charlotte, North Carolina. Furthermore, this research explored the gross vehicle weight (GVW) as a factor to account for pavement deterioration, emissions, and the effect of heavier vehicles on travel time and safety for charging vehicle owners. The cost to implement the recommended VMT fee is minimal, the driver's privacy is protected, and the VMT fee is less than $100 per year per vehicle for over 75% of the vehicle owners in the urban area.

Wireless technology is expected to undergo considerable transformation because of the numerous services offered by 6G communication networks, which virtually entirely encompass every part of everyday life and use a variety of devices. Channel modeling is an essential factor in designing 6G communication networks. To meet the channel requirements of future 6G communication networks, it is crucial to measure the channel to consider path loss, multi-band, fading, blocking effect, multipath clustering, transmitter, and receiver moving speed/direction/time. The goal of this paper is to design and evaluate a 6G communication network in Banda Aceh City using a statistical channel model. The channel model is associated with environmental conditions such as rainfall and humidity. The method is then based on computer simulation using the NYUSIM simulator to complete the channel modeling using an operating frequency of 95 GHz with a bandwidth of 800 MHz. In the simulator, the designed 6G chann...

Penggunaan sistem komunikasi cahaya tampak sebagai metode komunikasi alternatif selain RF didorong oleh beberapa faktor, salah satunya adalah penghematan energi karena sistem ini menggunakan satu devais yang sama untuk pencahayaan ruangan sekaligus komunikasi data yaitu LED. Penelitian ini bertujuan untuk memodelkan sistem komunikasi cahaya tampak berbasis multi-carrier modulation (yakni DCO-OFDM) dengan bantuan perangkat lunak MATLAB. Pada penelitian ini, sistem dimodelkan atas dua bagian yakni blok Digital Signal Processing (DSP) dan kanal optik. Blok DSP terdiri atas FFT, convolutional encoder, modulator-demodulator, interleaver-deinterleaver, dan synchronizer. Untuk error control coding (ECC) digunakan algoritma Viterbi decoder. Hasil penelitian menunjukkan bahwa frame DCO-OFDM telah berhasil didesain dan berdasarkan perhitungan matematis melalui pendekatan MATLAB, sistem VLC dapat bekerja dengan baik pada ruangan 5m x 5m x 3m, yakni BER = 0 untuk nilai minimum SNR = 10 dB, seme...

Single Carrier Frequency Division Multiple Access (SC-FDMA) merupakan bentuk modifikasi dari pendahulunya yaitu Orthogonal Frequency Division Multiple Access (OFDMA). Selektivitas frekuensi adalah kemampuan penerima untuk membedakan sumber-sumber sinyal yang dirancang untuk beroperasi pada frekuensi yang berbeda dan dalam rentang panjang gelombang tertentu. Analisis yang dilakukan adalah seberapa besar pengaruh selektivitas frekuensi terhadap penginterferensi pada Single Carrier Frequency Division Multiple Access (SC-FDMA). Semakin besar interferensi, maka performansi sistem akan semakin lemah

Single Carrier Frequency Division Multiple Access (SC-FDMA) merupakan bentuk modifikasi dari pendahulunya yaitu Orthogonal Frequency Division Multiple Access (OFDMA). Selektivitas frekuensi adalah kemampuan penerima untuk membedakan sumber-sumber sinyal yang dirancang untuk beroperasi pada frekuensi yang berbeda dan dalam rentang panjang gelombang tertentu. Analisis yang dilakukan adalah seberapa besar pengaruh selektivitas frekuensi terhadap penginterferensi pada Single Carrier Frequency Division Multiple Access (SC-FDMA). Semakin besar interferensi, maka performansi sistem akan semakin lemah

Personal mobility and vehicular transportation system are undergoing a shift towards more reactive and intelligent transport infrastructure. Wide range of applications and use cases have emerged in the vehicular environment facilitated by various wireless communication systems. These applications can be broadly classified into road safety, traffic efficiency and infotainment services, each with its own set of functional and performance requirements. Interoperability and coexistence of multiple radio access technologies provide opportunities to meet the application requirement by capitalising on the strengths of each technology. Two emerging Intelligent Transport System (ITS) technologies, namely Cellular Vehicle-to-Everything (C-V2X) and ITS-G5, are the focus of this work. A detailed qualitative comparison of the protocol stacks is provided along with performance evaluation of the standards. This work evaluates the performance of ITS-G5 and C-V2X for safety message application through simulation in a realistic highway scenario. The results indicate a superior performance by ITS-G5 in sparse vehicle density, delivering 80% of the beacons at a transmission frequency of 10 Hz. Moreover, ITS-G5 delivers beacons with less delay than C-V2X. C-V2X fares better for extremely dense networks in terms of delivering packets as well as inter reception time. It is inferred that appropriate resource allocation is vital in C-V2X to limit the transmission delay to within within 500 ms when delivering beacons to the destination node, without compromising on the packet reception ratio and inter reception time. ETSI's recently proposed co-channel coexistence methods for encouraging spectrum neutrality, that allows C-V2X and ITS-G5 to operate in the 5.9 GHz, leads to co-channel coexistence issues between the two technologies. This work provides the skeleton of a combined framework which can be used to further study the coexistence challenges. iv Sammanfattning Personlig rörlighet och fordonstransportsystem genomgår en förskjutning mot mer reaktiv och intelligent transportinfrastruktur. Ett brett spektrum av applikationer och användningsfall har dykt upp i fordonsmiljön underlättad av olika trådlösa kommunikationssystem. Dessa applikationer kan i stort sett klassificeras i trafiksäkerhet, trafikeffektivitet och infotainmenttjänster, var och en med sina egna uppsättningar av funktionskrav och prestandakrav. Interoperabilitet och samexistens av flera radioåtkomstteknologier ger möjligheter att uppfylla fordonets nätverksapplikationskrav genom att utnyttja styrkorna i varje teknik. Detta arbete fokuserar på två framväxande tekniker för intelligent transportsystem (ITS), nämligen 3rd Generation Partnership Project (3GPP) Cellular Vehicle-to-Everything C-V2X och ITS-G5. En detaljerad kvalitativ jämförelse av protokollstakarna tillhandahålls tillsammans med resultatutvärdering av standarderna. Detta arbete utvärderar prestanda för 802.11p och LTE-V2X för säkerhetsmeddelandetillämpning genom simulering i ett realistiskt motorvägscenario. Resultaten indikerar en överlägsen prestanda med IEEE 802.11p i gles fordonsdensitet, vilket levererar 80% av paketen med 10 Hz fyrfrekvens. Dessutom levererar ITS-G5 paket med mindre fördröjning än C-V2X. C-V2X presterar bättre för mycket tätt nätverk när det gäller att leverera paket samt intermottagningstid. Det dras slutsatsen att lämpliga resursallokeringar (resursblock och MCS) bör göras för att begränsa förseningen i att leverera paket till destinationsnoderna inom 500 ms utan att kompromissa med paketmottagningsförhållandet och intermottagningstiden, särskilt för mycket täta nätverk. ETSI: s nyligen föreslagna samexistensmetoder för samkanal för att uppmuntra spektrumneutralitet, som tillåter C-V2X och ITS-G5 att arbeta i 5,9 GHz, leder till samkanaliska samlivsfrågor mellan de två teknologierna. Detta arbete tillhandahåller skelettet i en kombinerad ram som kan användas för att ytterligare studera samexistensutmaningarna.

Orthogonal Frequency Division Multiplexing (OFDM) is a widely known modulation scheme used for high speed data transmission (like video) on multipath fading channels. The multipath components of these channels cause a frequency selective fading that seriously degrade the OFDM transmission, due to the erroneous exist on the received data. Time guard-interval is used to reduce intersymbol interference (ISI) and Intercarrier interference (ICI). Convolutional coding protects digital data from errors by selectively introducing redundancies in the transmitted data. In this paper a study of a combined use of Convolutional coding and OFDM technique is presented. The effect of coding rates and constraint lengths of the Convolutional code and the time guard interval of the OFDM symbols are studied under frequency selective environment through computer simulation. Recommendations for design issues are also discussed.

Ray launching (RL) algorithms are widely employed in indoor radio frequency (RF) design and planning, where a trade-off exists between the prediction accuracy and the computational cost. In this paper, a RL-based channel simulation is carried out in a simplified three-dimensional (3D) model of a typical classroom environment at the Ka-band. Channel measurements are conducted in a practical scenario to verify the accuracy of the simulations. The path loss and root mean square (RMS) delay spread of the propagation channel obtained from simulations and measurements are reported and compared, which show good agreements.

Penelitian ini mengusulkan desain program simulasi penerapan kode Bose Chaudhuri Hocquenghem (BCH) pada Direct Sequence Spread Specterum (DSSS) untuk mengetahui kinerja pengaruh DSSS dengan kanal flat fading dan AWGN tanpa pengkodean BCH (7,4) dengan penerapan kode BCH (7,4) pada DSSS dengan kanal flat fading dan AWGN. Simulasi ini terdiri dari simulasi BER penerapan kode BCH (7,4) pada DSSS dengan kanal flat fading dan AWGN, simulasi BER penerapan kode BCH (7,4) pada DSSS dengan kanal AWGN, simulasi pengaruh Eb/No terhadap varian noise pada sistem DSSS dan simulasi BER sebagai fungsi varian noise. Simulasi penerapan kode BCH (7,4) pada DSSS dengan kanal flat fading dan AWGN dianalisis berdasarkan Bit Error Rate (BER) berbanding Energy Bit per Noise (EbNo). Penerapan kode BCH (7,4) pada DSSS dengan kanal flat fading dan AWGN menghasilkan kinerja lebih baik dari DSSS dengan kanal flat fading dan AWGN tanpa pengkodean BCH (7,4). Pada nilai Eb/No 10 dB, simulasi penerapan kode BCH (7,4) pada DSSS dengan kanal flat fading dan AWGN menghaslikan nilai BER yang lebih mendekati 0 dengan nilai BER 0,0188, sedangkan simulasi DSSS dengan kanal flat fading dan AWGN tanpa pengkodean BCH (7,4) menghasilkan nilai BER 0,0228.

Activated microglia play a signi cant role in synaptic elimination during neuroin ammation, however, the events prior to the uptake of synaptic material by these cells remain elusive. Here, we performed in vivo two-photon imaging of microglia-synapse interactions in the context of systemic in ammation and Alzheimer´s disease. Both treatments induced microglial activation and decreased the basal surveillance of synapses by microglia. Focal synaptic stress was necessary to promote long-lasting microglia-neuron contacts and exacerbate spine elimination. The rate of spine elimination strongly correlated with the frequency of synaptic lopodia generation and microglial expression of phagocytic proteins. We show that activated microglia largely eliminate spines through phagocytosis rather than promoting their rapid retraction into dendrites. Moreover, we found that activated microglia induce the physical stretching of spines and their phagocytosis via the induction of spine head lopodia. Our real-time observations highlight key factors and decision points governing synaptic elimination by microglia during neuroin ammation.

Transmisi optik nirkabel dengan kecepatan tinggi memiliki berbagai potensi untuk aplikasi jarak pendek terutama untuk komunikasi di dalam ruangan. Tulisan ini memaparkan perbandingan kinerja transmisi FSO menggunakan beberapa variasi skema modulasi. Pengamatan unjuk kinerja terutama dilakukan menggunakan bit error rate (BER). Gangguan turbulensi atmorferik menjadi bagian dari pemodelan kanal log normal yang digunakan dalam simulasi. Modulasi dasar spasial yang digunakan adalah on-off keying sebagai teknik klasik FSO, beserta pulse position modulation yang merupakan variasi spasialnya. Menelaah penggunaan modulasi baseband untuk sistem optik, disimulasikan PSK 2, 4, 8, 16, serta QAM 4 dan 16. Simulasi dengan data ukuran kecil menghasilkan bahwa BPSK dan 4 QAM menunjukkan unjuk kerja terbaik dengan BER rata-rata sekitar 10-3 pada kondisi gangguan sedang sampai tinggi. Sementara tingkat error pada OOK dan PPM masih di atas 10-0.5 .

Achieving adequate coverage with high gain antennas is key to realizing the full promise of the wide bandwidth available at cm/mm bands. We report extensive outdoor measurements at 28 GHz in suburban residential areas in New Jersey and Chile, with over 2000 links measured for same-street link types (vegetation blocked LOS) from 13 streets and otherstreet link types (true NLOS) from 7 streets, using a specialized narrowband channel sounder at ranges reaching 200 m. The measurements, applicable to fixed wireless access, involved a 55 • transmit antenna placed on the exterior of a street-facing window and a 10 • receive horn antenna spinning on top of a van mast at 3 m height, emulating a lamppost-mounted base station. Measured path gain-distance dependence is well represented by power-law models, and azimuth gains at the base are degraded through scattering by more than 4.3 dB for 10% of links. It was found that, with 51 dBm EIRP at the base station and 11 dBi antenna at an outdoor mounted terminal, 1 Gbps downlink rate can be delivered up to 100 m from a base station deployed in the same street with 90% coverage guarantee.

Propagation measurements at 28 GHz were conducted in outdoor urban environments in New York City using four different transmitter locations and 83 receiver locations with distances of up to 500 m. A 400 mega-chip per second channel sounder with steerable 24.5 dBi horn antennas at the transmitter and receiver was used to measure the angular distributions of received multipath power over a wide range of propagation distances and urban settings. Measurements were also made to study the small-scale fading of closely-spaced power delay profiles recorded at halfwavelength (5.35 mm) increments along a small-scale linear track (10 wavelengths, or 107 mm) at two different receiver locations. Our measurements indicate that power levels for small-scale fading do not significantly fluctuate from the mean power level at a fixed angle of arrival. We propose here a new lobe modeling technique that can be used to create a statistical channel model for lobe path loss and shadow fading, and we provide many model statistics as a function of transmitterreceiver separation distance. Our work shows that New York City is a multipath-rich environment when using highly directional steerable horn antennas, and that an average of 2.5 signal lobes exists at any receiver location, where each lobe has an average total angle spread of 40.3° and an RMS angle spread of 7.8°. This work aims to create a 28 GHz statistical spatial channel model for future 5G cellular networks.

Omnidirectional path loss models are vital for radiosystem design in wireless communication systems, as they allow engineers to perform network simulations for systems with arbitrary antenna patterns. At millimeter-wave frequencies, channel measurements are frequently conducted using steerable highgain directional antennas at both the transmitter and receiver to make up for the significant increase in free space path loss at these frequencies compared to traditional cellular systems that operate at lower frequencies. The omnidirectional antenna pattern, and resulting omnidirectional received power must therefore be synthesized from many unique pointing angles, where the transmit and receive antennas are rotated over many different azimuth and elevation planes. In this paper, the equivalent omnidirectional antenna pattern and omnidirectional received power are synthesized by summing the received powers from all measured unique pointing angles obtained at antenna halfpower beamwidth step increments in the azimuth and elevation planes, and this method is validated by demonstrating that the synthesized omnidirectional received power and path loss are independent of antenna beamwidth, through theoretical analyses and millimeter-wave propagation measurements using antennas with different beamwidths. The method in this paper is shown to provide accurate results while enhancing the measurement range substantially through the use of directional antennas.

This article provides 28 GHz and 73 GHz urban omnidirectional propagation path loss data measured in downtown New York City during the summers of 2012 and 2013, and 38 GHz data measured in downtown Austin in the summer of 2011. The data provided herein may be used by antenna, propagation, and communications researchers for emerging mobile and/or backhaul millimeter-wave path loss models. This article also presents measurement layout maps with TX and RX locations and GPS coordinates, so that anyone may create similar or new measurements and models, or may perform further processing such as with ray-tracers and modeling tools, in addition to studying millimeter-wave system performance. Using the data provided herein, large-scale path loss models using a standard close-in free space reference distance are provided for each of the three frequency bands.

The objective of this research is to gather data for an urban area, evaluate, and assess the applicability of vehicle miles traveled (VMT) fee to replace or complement the gas tax, and mitigate the local transportation finance deficit. Vehicle data collected from three geographically distributed service stations in Charlotte, North Carolina were used to evaluate multiple VMT fee scenarios. The results indicate that charging 0.625 cents per each mile traveled or 1.00 cent per additional mile exceeding 5,000 miles per year, to complement the gas tax, could generate enough revenue to mitigate the transportation finance deficit estimated equal to $30 M to $35 M at the time of this research for the city of Charlotte, North Carolina. Furthermore, this research explored the gross vehicle weight (GVW) as a factor to account for pavement deterioration, emissions, and the effect of heavier vehicles on travel time and safety for charging vehicle owners. The cost to implement the recommended VMT fee is minimal, the driver's privacy is protected, and the VMT fee is less than $100 per year per vehicle for over 75% of the vehicle owners in the urban area.

The practical method of worst-case estimation of the total electromagnetic background near ground surface created by different radio systems is offered. This method takes into consideration heterogeneity of radioelectronic environment formed by the full set of stationary and mobile transmitters of different radio services, and peculiarities of radio wave propagation on different distances between transmitters and observation point, and of statistical features of electromagnetic fields in observation point generated by these transmitters. The presented method allow to estimate the fundamental upper bound of electromagnetic background total intensity created by heterogeneous radioelectronic environment, directly on the basis of estimation of the total electromagnetic loading on territory as the total equivalent isotropic radiated power of full set of transmitters of all services falling to the unit of the area of considered territory. The presented results ensure the facilities of EMC diagnostics and design of ultra wide band radio systems using nonsine radio waves, and cognitive radio systems using frequency bands on the secondary basis, and of support of the acceptable electromagnetic environmental conditions in populous areas. Keywords-electromagnetic background, electromagnetic loading, heterogeneous radioelectronic environment, cognitive radio, EMC diagnostics, cellular communications. I. ABBREVIATIONS CDF-cumulative distribution function. EMB-total electromagnetic background in observation point. EME-electromagnetic environment. EMF-electromagnetic field. EML-electromagnetic loading (on territory). EMR-electromagnetic radiation of radio transmitter. EIRP-equivalent isotropic radiated power. MPL-maximum permissible level. MTR-mobile transmitter. OP-observation point. PDF-probability density function. PFD-power flux density of EMF. REE-radioelectronic environment. RWP-radiowave propagation.

Поступила в редакцию 14 апреля 2011 Приведены оценки предельно допустимого объема радиочастотного ресурса, выделяемого сотовой радиосети стандарта GSM 900/1800, при котором обеспечиваются безопасные уровни электромагнитного излучения сотовых телефонов при различных чувствительности радиоприема в сети, размерности кластера частотного планирования и удельной интенсивности трафика.