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"The field of radio communications continues to change rapidly and the second edition of this outstanding book, based on a popular IEE Vacation School, has been fully updated to reflect the latest developments. The introduction of new services and the proliferation of mobile communications have produced a growing need for wider bandwidths and the consequent need for frequency reuse. This book introduces the basic concepts and mechanisms of radiowave propagation engineering in both the troposphere and ionosphere, and includes greater emphasis on the needs of digital technologies and new kinds of radio systems. The content reflects the wide experience of an exceptional group of authors and the emphasis throughout is on modelling and prediction methods and the relevant ITU Radiocommunication sector recommendations. Propagation of Radiowaves, 2nd Edition is essential reading for professionals involved in planning, designing and operating radio systems."

"ABSTRAKUntuk menilai performa dari sistem komunikasi tanpa kabel, salah satu yang sangat diperlukan adalah menghitung kemampuan dalam memperoleh informasi. Performa dari beberapa sistem ditentukan oleh kapasistas kanal dari sistem tersebut. Tentunya, semakin besar kapasitas kanal dari sebuah sistem akan semakin baik sistem tersebut dimana kemampuan untuk memperoleh informasi akan semakin besar. Kebutuhan akan kapasitas kanal yang maksimal tentunya sangat mendasar mengingat akan kebutuhan manusia akan komunikasi yang terus meningkat. Pada tesis dibahas tentang analisis kapasitas kanal menggunakan pengukuran propagasi gelombang pada frekuensi UHF- S Band dengan karakterisasi ketinggian. Analisis ini bertujuan untuk mengetahui besar kapasitas kanal pada beberapa ketinggian yang diukur. Perhitungan kapasitas kanal menggunakan persamaan yang merepresentasikan kapasitas kanal, yaitu teorema kapasitas kanal Shannon Shannon channel capacity theorem .Pengukuran dilakukan pada frekuensi 800 MHz, 1800 MHz, 2400 MHz dan 3300 MHz di lingkungan Fakultas Teknik Universitas Indonesia. Pengukuran dilakukan dengan meletakan antena penerima dengan ketinggian yang tetap yaitu 2 m sedangkan antena penerima diletakan pada ketinggian 1 m, 2 m, 5 m, 10 m, dan 15 m. Pada masing masing frekuensi dilakukan pengukuran dengan tiga kondisi yaitu dengan menghadapkan antena ke atas, ke tengah dan ke bawah.Hasil pengukuran kemudian diolah dan dianalisa untuk melihat pengaruh variasi ketinggian penempatan antena pengirim dan penerima terhadap kapasitas kanal. Dengan melihat keseluruhan hasil perhitungan kapasitas kanal dari hasil pengukuran pada masing masing frekuensi, dapat kita ketahui bahwa kapasitas kanal akan menurun ketika antena pengirim diletakan semakin tinggi dari permukaan tanah. Dengan kata lain, kapasitas kanal terbesar adalah ketika antena pengirim ditempatkan lebih dekat ke tanah.

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ABSTRACTTo assess the performance of a wireless system, one needs to quantify its ability to handle information. Typically, the performance of such systems is Characterized in terms of the channel capacity. Obviously, the greater the channel capacity of a system, the better the system where the ability to obtain information will be greater. The need for maximum channel capacity is certainly very fudamental, because the human need for communication is immediately increase. This thesis discusses about Analysis of Channel Capacity Through Wave Propagation Measurement in UHF S Band Frequency WIth High Characterization. This analysis aims to determine the capacity of the canal at some high measurement. Calculation of channel capacity uses an equation representing channel capacity, which is Shannon channel capacity theorem.The measurements are made at frequencies of 800 MHz, 1800 MHz, 2400 MHz and 3300 MHz in the Faculty of Engineering Universitas Indonesia. The measurement is done by placing the receiving antenna with a fixed height of 2 m while the receiving antenna is placed at 1 m, 2 m, 5 m, 10 m, and 15 m. At each frequency is measured with three conditions that is by facing the antenna up, to the middle and down.The results of these measurements will be processed and analyzed to see the effect of high variations in the placement of the transmitter and receiver antenna to channel capacity. By looking at the overall calculation of channel capacity from measurement results on each frequency, we can know that the channel capacity will decrease when the transmitter antenna is placed higher. In other words, the largest channel capacity is when the transmitter antenna is placed closer to the ground."

"Komunikasi bergerak adalah teknologi telekomunikasi yang banyak memberikan kemudahan kepada penggunanya dalam berkomunikasi. Perencanaan dalam penempatan Base Transceiver Station (BTS) harus direncanakan sebaik mungkin untuk memperkecil kemungkinan terdapatnya daerah lubang (blank-spot) pada daerah dimana BTS akan ditempatkan. Pendeteksian daerah lubang menggunakan komputer dapat mempermudah proses perencanaan penempatan BTS di daerah pegunungan. Di dalam penelitian ini, dirancang perangkat lunak untuk mendeteksi daerah lubang sesuai dengan spesifikasi BTS. Selain itu simulasi letak ponsel terhadap BTS juga dapat diperhitungkan agar diketahui apakah ponsel tersebut dapat mengirimkan sinyalnya kepada BTS. Pendeteksian daerah lubang dilakukan dengan menghitung besarnya kuat medan yang diterima oleh penerima dengan menggunakan metode UTD (Uniform Theory of Diffraction). Hasil perhitungan ditampilkan dalam peta dua dimensi daerah pegunungan dengan kawasan berwarna hitam sebagai indikasi daerah lubang dan warna putih sebagai daerah jangkauan komunikasi. Faktor yang memengaruhi luas daerah lubang adalah: nilai Effective Isotropic Radiated Power-EIRP berbanding terbalik dengan jumlah daerah lubang, sensitivitas antena berbanding lurus dengan jumlah daerah lubang. Sementara ketinggian antena BTS tidak terlalu signifikan pengaruhnya terhadap jumlah daerah lubang yang muncul.

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Mobile communication is a technology that makes communication easier. Network planning must be performed carefully to reduce the probability of blank spot in an area which Base Transceiver Station (BTS) is placed.

Detection of blank spots in mountainous area using computer simplifies the placement BTS in network planning. In this research, a simulation software is built to detect blank spots. The simulation covers blank spots detection in the BTS coverage and signal detection from mobile phone.

Blank spots was detected by calculating the field intensity received by the mobile phone using Modified UTD (Uniform Theory of Diffraction) method. The output of the simulation is an image consisted of two colours, black and white, which represented the blank spot and receiving areas, respectively. The larger antenna sensitivity, resulted in smaller area of blank spots, while EIRP and. While the height of BTS antenna was not so significant to determine the area of blank spots."

"Propagation engineering in wireless communications covers the basic principles needed for understanding of radiowaves propagation for common frequency bands used in radio-communications. This book includes descriptions of new achievements and new developements in propagation models for wireless communication. The book is intended to bridge the gap between the theoretical calculations and approaches to the applied procedures needed for radio links design in a proper manner. The authors intention is to emphasize propagation engineering by giving sufficient fundamental information and then going on to explain the use of basic principles together with technical achievements in this field."

"ABSTRAKKebutuhan akan komunikasi dan transfer data berkembang pesat di beberapa dekade terakhir. Untuk mendapatkan data transfer yang lebih tinggi, perlu ditentukan peletakan antena yang tepat pada suatu sistem nirkabel. Pada tulisan ini, kami melakukan pengukuran propagasi di lingkungan iklim tropis dan pada rentang UHF ndash; S Band dengan melakukan pengukuran variasi jarak dari 10 m ndash; 100 m pada frekuensi 800 MHz, 1.8 GHz, 2.4 GHz, dan 3.3 GHz.Hasil pengukuran dibandingkan dengan nilai perhitungan dengan model-model propagasi seperti Free-Space Loss, Okumura-Hata urban dan Okumura-Hata suburban. Kemudian dianalisa untuk mengetahui pengaruh jarak terhadap kuat medan yang diperoleh. Setelah dilakukan pengukuran dan perhitungan, nilai daya yang diterima menurun seiring dengan jarak yang bertambah dan hal ini berlaku pada setiap frekuensi. Terdapat beberapa penyimpangan saat pengukuran karena pengaruh dari lingkungan sekitar. Dari kuat medan yang diperoleh tersebut dilakukan perhitungan kapasitas kanal Shannon yang kemudian dianalisa untuk mengetahui pengaruh dari kuat medan terhadap kapasitas kanal. Nilai kapasitas kanal yang diperoleh menurun seiring dengan menurunnya nilai kuat medan yang diperoleh. Hasil ini dapat digunakan untuk mengetahui kapasitas kanal maksimum dengan memperhatikan konfigurasi antena terbaik berdasarkan daya yang diterima.

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ABSTRACTCommunication and data transfer demands are growing fast in last few decades. To obtain a higher data transfer, it is necessary to determine proper antenna placement in a wireless system. In this paper, we conduct a propagation measurements in tropical environments and UHF S Band frequency by conducting distance variation from 10 m ndash 100 m at frequency 800 MHz, 1.8 GHz, 2.4 GHz, and 3.3 GHz.The measurement results were compared with the calculation result which has been calculated using propagation models such as Free Space Loss, urban Okumura Hata and suburban Okumura Hata. The result were analyzed to determine the effect of distance to the field strength obtained. After measurement and calculation, the received power level decreases as the distances increases and this applies to every frequency. There are several deviations during measurement due to the influence of the surrounding environment. Shannon channel capacity were calculated using the field strength obtained. The result were analyzed to determine the effect of field strength to channel capacity. The value of obtained channel capacity decreases as the field strength value obtained decreases. This result can contribute to determine the maximum channel capacity by considering an optimum antenna configuration based on received power levels."

"ABSTRACTBeberapa tahun kebelakang ini telah terjadi pertumbuhan yang sangat cepat di bidang komunikasi radio dan teknologi nirkabel. Seiring munculnya layanan baru, divais nirkabel, dan peningkatan jumlah data yang ditransmisikan antara sesama pengguna divais nirkabel, maka optimasi sistem komunikasi nirkabel di suatu area geografis sangat dibutuhkan. Salah satu caranya adalah dengan membuat model propagasi gelombang. Skripsi ini membahas model propagasi gelombang radio pada lingkungan microcellular menggunakan metode ray tracing. Metode ray tracing yang berdasarkan geometrical optics GO dan uniform theory of diffraction UTD , digunakan untuk menghitung rugi-rugi lintasan sepanjang jalur tertentu pada lingkungan line-of-sight LOS maupun non-line-of-sight NLOS . Konfigurasi dan parameter yang digunakan bertujuan untuk mengetahui karakteristik propagasi gelombang berdasarkan material pemantul, tinggi antena, lebar jalan, frekuensi karir dan jenis polarisasi yang digunakan. Berdasarkan hasil simulasi diperoleh bahwa frekuensi karir yang digunakan memiliki pengaruh yang signifikan terhadap nilai rugi-rugi lintasan, kemudian ketika tinggi antennapemancar meningkat, makabreakpoint meningkat sehingga tingkat atenuasi daya berkurang. Diperoleh path loss exponent pada skenario urban canyon berkisar pada 1.1 hingga 2.1. Diperoleh pula hasil simulasi dengan metode ray tracing pada skenario yang spesifik memiliki kecocokan dengan urban microcellular UMi path loss model. Pada area Nihonbashi diperoleh nilaipath loss exponent pada kisaran 1.5 hingga 2.3 dan pada lingkungan Fakultas Teknik Universitas Indonesia pada kisaran 1.3 hingga 2.1.

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ABSTRACTIn the past few years there has been a very rapid growth in the field of radio communications and wireless technology. As new services emerge, wireless devices, and an increase in the amount of data transmitted between wireless device users, the optimization of wireless communications systems in a geographical area is needed. One way is to make wave propagation model. This thesis discusses radio wave propagation model in microcellular environment using ray tracing method. The ray tracing method based on geometrical optics GO and uniform theory of diffraction UTD , is used to calculate track losses along certain paths in line of sight LOS and non line of sight NLOS environments. The configuration and parameters used to find out the wave propagation characteristics based on reflector material, antenna height, road width, career frequency and type of polarization used. Based on the simulation result, it is found that the career frequency used has a significant influence on the path loss value, then when the transmitter height increases, the break point increases so that the power attenuation level decreases. It is obtained that the path loss exponent in the urban canyon scenario ranges from 1.1 to 2.1. The simulation results obtained by ray tracing method in a specific scenario have a compability with urban microcellular UMi path loss model. In the Nihonbashi area the path loss exponent value is obtained in the range 1.5 to 2.3 and in the environment of the Faculty of Engineering University of Indonesia in the range of 1.3 to 2.1."