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Comparison of WiMAX coverage at 450MHz and 3.5GHz Tomaz Javornik, Gorazd Kandus, Andrej Hrovat, Igor Ozimek Department of Communication Systems Jozef Stefan Institute, Jamova 39 Ljubljana, Slovenia tomazJavornikijssi, gorazd.kandus Abstract In this paper we calculate, analyze and compare area covered by radio signal based on WiMAX standard at two carrier frequencies, namely 450MHz and 3.5GHz in flat rural, hilly rural and urban environment. The channel model proposed by WiMAX forum has been applied as path loss model at 3.5GHz for cell coverage prediction, while at 450MHz the Longley-Rice model for rural areas and Okumura Hata channel models for urban area is used. The cell size prediction strongly suggests to limit the 3.5GHz frequency band to urban areas, where the higher system capacity is required, while in rural areas the 450MHz carrier frequency provide good compromise between coverage and system capacity. - the Index Terms- HPA, WiMAX, system capacity, calculation coverage INTRODUCTION T he provision of Internet access and broadband multimedia services to residential users via wireless communication systems attracted an increasing interest of the research community, service providers and the telecommunication industry. The WiMAX specifications , which are a subset of IEEE 802.16 standard, seems to be the winner for providing a wireless access in urban, suburban and rural environment with non line of sight (NLOS) propagation, thus in a harsh multipath propagation environment. The WiMAX specification proposes 256 orthogonal frequency division multiplex (OFDM) approach to cope with expected channel impairments. Among all subcarriers only 192 of them...
The performance of co-located WiMAX transmitter sites operating at 2.5 and 3.5GHz are compared, based on coverage assessments. The study showed that the 2.5GHz performed marginally better than the 3.5GHz under the same RF conditions and clutter environments. In general, the 2.5GHz was found to provide slightly better coverage at the edge of the cell, with an average of 2dB less loss at 1km from the transmitter location. Comparisons of the path loss difference between these two frequencies with various empirical propagation models (COST-Hata, ECC-33, WINNER II-Suburban, SUI Flat) were made, and differences from 2.9 dB to 6.2 dB are reported from these models, which are much larger than those reported here (around 2 dB for outdoor). These differences are also dependent on the distance to the site. Indoor penetration loss was found to be around 1 dB. • • Impact on site configuration Impact of local clutter Section 2 of this paper goes through the data collection methodology applied during the measurement campaign. Section 3 provides the results of the comprehensive data set collected during the surveys. In section 4, we summarise the results and attempt to give an indication of what the results translate to in terms of network infrastructure requirement.
Frequently Asked Questions Resources Educators are becoming increasingly aware of the beneﬁts of properly Q: How do districts make sure they have coverage everywhere? • K12Blueprint.com implemented online digital materials and tools. Not only are these more A: In general, coverage is not an issue if there is line-of-sight access • K12WiMAX.com current and engaging than their print and paper-and-pencil counterparts, they are more cost-effective at both the district and state level. However, to maximize their effectiveness, digital materials and tools must to a tower. Just as in cell phone networks, dead spots occur unless antennas are placed correctly and in sufﬁcient quantity. In rugged terrain or dense urban areas, this may not always be economically feasible. be available to students wherever and whenever they are needed. Q: How do districts ensure sufﬁcient network capacity? WiMAX* provides this capability, allowing students and families access to A: Capacity is related to coverage. Just as cell phone networks all the required educational resources anytime, anywhere, and contributing to a truly transformed learning system. “Always-on” Internet access is likely to introduce a powerful new paradigm into our education system, have dropped calls, if too many units try to access a single antenna there will be negative consequences. Additional towers, antenna segments, and Internet backhaul capacity can remedy this situation. just as the cell phone paradigm changed our society at large. Q: Which spectrum should districts use? Learning is no longer limited to the school and home, but can take place A: Districts that have an EBS licensee with available spectrum in the park, on the bus, or while waiting for a sibling at the soccer ﬁeld.
Abstract—WIMAX signal throughput and area coverage range are the most important factors that will affect the quality of broadband access services in mobile systems. This paper presents a comprehensive study of frequency analysis for path loss on mobile WIMAX presented to achieve large throughput and wide coverage to a big number of users. In this paper we have calculated the path loss values based on the variation of WIMAX standard frequency in the range of 2 to 6 GHz, and a fixed distance of 5 km from the transmit station to the receive station in urban, suburban, rural and free space environments. The paper discusses and implements Okumura, Hata, Cost-231, Ericsson, Erceg, Walfish, Ecc-33, Lee and the simplified free space path loss models. All the models applied in this paper are used to predict the propagation loss for WIMAX. ... In this paper we evaluate the path loss at various environments in WIMAX for frequencies 2 to 6 GHz, and fixed distance of 5 km. We characterize the variation in path loss over distance for various environments. In this study, since the transmission from the BS to the MS is small enough, so it will not be affected by the earth’s curvature. Link budget is used to find and estimate the coverage area of a cellular system cell. Path loss is used to calculate the link budget. Therefore link budget calculations could be performed using our results of WIMAX. In addition, path loss can be used to calculate and estimate the required number of BS’s for different environments.
Assalamu’alaikum Warahmatullahi Wabarakatuh Tiada kata-kata indah yang pantas diucapkan selain puji syukur Alhamdulillah, kepada Allah Subhanahuwata’ala, sebab dengan rahmat, nikamat dan karuniaNya penulis dapat menyelesaikan tulisan ini. Walaupun dalam bentuk dengan isi sederhana yang terangkum dalam tesis berjudul “Pengadaan Barang/Jasa Publik dalam Rangka Pelaksanaan Kerja Sama Daerah”, sebagai persyaratan untuk menyelesaikan studi Pasca Sarjana Program Studi Magister Kenotariatan Universitas Diponegoro Semarang Tahun 2008. Sebagai insane yang lemah tentunya banyak sekali kekurangan-kekurangan dan keterbatasan yang terdapat pada diri penulis tidak terkecuali pada penulisan tesis ini, oleh karena itu penulis sangat mengharapkan koreksi, kritik saran dan perbaikan dari berbagai pihak agar penulisan tesis ini lebih baik. Tidak sedikit bantuan dari berbagai pihak yang diberikan kepada penulis baik dari segi moril dan segi materiil. Oleh karena itu dengan segala ketulusan hati penulis mengucapkan beribu-ribu terima kasih atas segala bantuan dan dukungan yang selama ini penulis terima sehingga penulisan tesis ini dapat diselesaikan. Pada kesempatan yang ini, ijinkanlah penulis mengucapkan rasa terima kasih kepada : 1. Bapak H. Mulyadi,S.H.,M.S. selaku Ketua Program pada Program Studi Magister Kenotariatan Universitas Diponegoro Semarang, yang selalu memberikan motivasi dalam menyelesaikan tesis ini. 2. Bapak Dr.R.Benny,S.H.,C.N.,M.Hum., sebagai Dosen Pembimbing Utama dalam penulisan tesis ini yang telah banyak membantu memberikan bimbingan dalam menyelesaikan penulisan ini. 3. Bapak Yunanto,S.H.M.Hum., sebagai Sekretaris I Bidang Akademik, sekaligus sebagai Dosen Penguji di Program Kenotariatan Universitas Diponegoro. 4. Bapak Sonhaji,S.H.,M.S., dan Bapak Hendro Saptono,S.H.,M.Hum., sebagai Dosen Penguji di Program Kenotariatan Universitas Diponegoro. 5. Semua Narasumber selama kami melaksanakan penelitian, seperti Bapak Joko Pranowo,S.H.,M.H., Kepala Bappeda Kabupaten Pekalongan, Bapak Achmad Mas’udi,S.H.,.M.M., Kepala Dinas Pendapatan Daerah Kabupaten Pekalongan, Bapak Harry Suminto,S.H.,M.H., Kepala Bagian Hukum Setda Kabupaten Pekalongan, Bapak Drs.H. Abidin Noor Kepala Bagian Aset Daerah Kabupaten Pekalongan dan Bapak Ir.Agus Prijambodo, Kepala Bagian Program Setda Kabupaten Pekalongan, yang telah memberikan bimbingan dan arahan dalam penulisan tesis ini. 6. Teristimewa untuk suamiku Abdul Aziz Sutanto,S.Sos. dan anak-anakku tersayang Iftita Rakhma Ikrima dan Shoffarisna Ithma’anna atas doa dan dukungannya selama ini sehingga penulis dapat menyelesaikan pendidikan di magister Kenotariatan Universitas Diponegoro Semarang. 7. Sahabat-sahabatku dan rekan-rekan Mahasiswa Program Magister Kenotariatan Universitas Diponegoro Angkatan 2006. 8. Semua pihak yang belum sempat penulis sebutkan dan telah banyak membantu penyelesaian tesis ini. Akhirnya, semoga amal baik mereka mendapat imbalan dan pahala dari Allah SWT. Amien. Semarang, penulis April 2008
iBooks includes the iBookstore, where you can download for free as well as purchase books. Features include bookmarking, highlighting, annotating, and speak selection. Kindle gives users the ability to read Kindle books. You’ll have access to over 950,000* books in the Kindle Store, including best sellers and new releases. Overdrive allows users to borrow ebooks and audiobooks from your local library and read/listen to them on the iPad. You must have a local library card to use this app. Productivity Apps Bamboo Paper Dragon Dictation Explain Everything iBrainstorm inClass iStudiez Pro Bamboo Paper provides you with the ability to create virtual notebooks and share your ideas visually with handwritten notes, sketches or doodles. Dragon Dictation is an easy-to-use voice recognition application that allows you to speak and instantly see your text. Explain Everything is a design tool that lets you annotate, animate, and narrate explanations and presentations. Create interactive lessons, activities, assessments, and tutorials. iBrainstorm is a multi-device collaboration tool that gives up to four people the ability to create ideas on their iPhones and flick them over to the iPad. inClass allows students to organize their schedules, notebooks, courses, and tasks. Students can create video, audio , and photo notes. iStudiez Pro provides students a built-in planner to organize schedules and a section to keep track of homework and assignments. Notability Notability integrates handwriting, PDF annotation, typing, recording, and organizing your notes and share your annotations using email, dropbox, and more. Note Hub Note Hub allows you to create projects with unlimited Notes, Drawings, Task lists, web browsers, maps, and calculators.
This paper addresses the requirements for the semiconductor sensing circuitry and SCR crowbar devices used in DC power supply over/under voltage protection schemes. The Zener Sense Circuit The simplest way to protect against overvoltage is to use a Zener diode to sense the output voltage (Figure 1). When the Zener goes into avalanche, it triggers the SCR. There are problems with this kind of protection: 1. No threshold adjustment, except by selecting different Zener diodes. 2. Inability to ignore momentary transients. 3. Poor SCR reliability caused by inadequate trigger–current rise time when slowly varying voltage is sensed. INTRODUCTION It is uncommon now to find several hundred dollars worth of microprocessors and memory chips powered from a single low DC supply. If this supply on the board doesn’t have overvoltage or undervoltage protection, potentially large sums of money can literally go up in smoke due to component failure, or, for instance, a tool may be accidentally dropped across the supply buses of different voltages during testing or repair of the system.
When a control system is implemented in a distributed fashion, with multiple processors communicating over a network, both the communication delays associated with the network and the computation delays associated with the processing time can degrade the system’s performance. In this case, the performance of the system may depend not only on the performance of the individual components but also on their interaction and cooperation. The approach taken in this paper assumes that the control has been designed without taking into account the network architecture. A theoretical framework is presented which allows the eﬀect of time delays on the mechanical performance of the system to be precisely modeled, and these models are used to determine the optimal network architecture for the given control system. A design example of a two-axis contouring system is presented.
Advanced Process Control A complete suite of process optimization products ABB, as the world leading supplier in automation systems, offers a complete suite of solutions aimed at the optimization of industrial processes. With numerous installations in the oil and gas, pulp and paper, and power generation industries, APC has a proven success rate in squeezing more production at lower cost from complex and demanding processes. Process control from the global market leader For more than 30 years ABB’s application engineers have faced and tamed every possible control problem in just about every conceivable process control application. Over the decades we have provided thousands of advanced process control and optimization solutions, many of which are based on our powerful Advanced Process Control (APC) suite of control and optimization products. ABB brings a wealth of expertise and customer commitment to every control project. We have the world’s largest installed base of process automation systems, and we are consistently ranked the world leader in distributed control systems, both for the DCS market as a whole and in industry verticals like oil, gas, refining, petrochemical and chemical, pulp and paper, and minerals.
Abstract—By improvement of industries, the demand of using of feasible industrial control system (ICS) and optimizing the current method is growing. Distributed control system is one of the best and usual methods for controlling an industrial system. Simplicity, flexibility, extensibility, scalability, fault tolerance and accommodation are some of its features that caused this method outshine from the other methods and by using new technologies, new facilities can be added easily. Nowadays Information Technology (IT) science gives us various tools for optimization and better execution of DCS. This paper will introduce these tools and their usage and at the end a practical example including all of these tools will be presented.