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"This book describes the design and implementation of an electronic subsystem called the frequency synthesizer, which is a very important building block for any wireless transceiver. The discussion includes several new techniques for the design of such a subsystem which include the usage modes of the wireless device, including its support for several leading-edge wireless standards. "

"This book explains concepts behind fractional subsampling-based frequency synthesis that is re-shaping todays art in the field of low-noise LO generation. It covers advanced material, giving clear guidance for development of background-calibrated environments capable of spur-free synthesis and wideband phase modulation. It further expands the concepts into the field of subsampling polar transmission, where the newly developed architecture enables unprecedented spectral efficiency levels, unquestionably required by the upcoming generation of wireless standards.Guides development of DTC-based Fractional-N Subsampling PLL and Subsampling Polar Transmitters, covering material from fundamental theory, over system level considerations to building block IC implementation;Describes a fully background-calibrated environment that can used in general context of fractional frequency synthesis and/or phase/frequency modulation;Presents three IC implementations, showing system level analysis, design methodology, circuit details and measurement results."

"Spektrum frekuensi radio merupakan sumber daya alam terbatas yang dikuasai oleh negara yang bersifat strategis serta memiliki nilai ekonomis yang tinggi sehingga harus dikelola secara efektif dan efisien guna memperoleh manfaat yang optimal. Penggunaan spektrum frekuensi radio harus sesuai dengan peruntukannya serta tidak saling mengganggu mengingat sifat spektrum frekuensi radio yang dapat merambat ke segala arah. Dikarenakan masih banyaknya terdapat penggunaan frekuensi baik oleh masyarakat maupun penyelenggara, khususnya pada dinas siaran radio FM yang menggunakan frekuensi tidak dilengkapi dengan izin stasiun radio dan tidak sesuai dengan aturan alokasi frekuensi yang telah ditentukan serta juga penggunaan alat perangkat telekomunikasi yang tidak memiliki sertifikat, menyebabkan potensi terjadinya gangguan frekuensi yang merugikan atau harmful interference menjadi tinggi. Adapun kegiatan yang dilakukan meliputi kegiatan monitoring dan penertiban yang diawali dengan pengukuran frekuensi, identifikasi legalitas stasiun radio, deteksi sumber pancaran frekuensi, selanjutnya dilakukan inspeksi sebagai langkah penertiban terhadap pengguna frekuensi yang telah terbukti melakukan pelanggaran penggunaan frekuensi secara ilegal. Setiap tahapan kegiatan yang dilakukan telah menerapkan dan memperhatikan prinsip dan kaidah pokok ilmu keinsinyuran seperti profesionalisme, prinsip dasar kode etik dan etika profesi insinyur, serta unsur keselamatan kesehatan keamanan kerja dan lingkungan (K3L) sesuai dengan aturan perundang-undangan yang berlaku. Diharapkan dengan dilakukannya kegiatan pengawasan dan pengendalian spektrum frekuensi radio pada dinas siaran radio FM di wilayah layanan DKI Jakarta dapat menekan potensi terjadinya harmful interference, sehingga seluruh masyarakat pengguna frekuensi dapat memanfaatkan frekuensi dengan tertib, nyaman, dan aman dari gangguan-gangguan interferensi frekuensi yang merugikan.

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The radio frequency spectrum is a limited natural resource controlled by the state which is strategic in nature and has high economic value so it must be managed effectively and efficiently in order to obtain optimal benefits. The use of the radio frequency spectrum must be in accordance with its intended purpose and not interfere with each other considering that the nature of the radio frequency spectrum can propagate in all directions. Because there is still a lot of frequency use by both the public and organizers, especially in the FM radio broadcast service which uses frequencies that are not equipped with radio station permits and do not comply with predetermined frequency allocation rules and also the use of telecommunications equipment that does not have a certificate, causes the potential for harmful frequency interference or harmful interference becomes high. The activities carried out include monitoring and controlling activities starting with frequency measurements, identifying the legality of radio stations, detecting frequency emission sources, then carrying out inspections as a control measure against frequency users who have been proven to have committed illegal frequency use violations. Each stage of activity carried out has implemented the basic principles and rules of engineering science such as professionalism, basic principles of the code of ethics and professional ethics of engineers, as well as paying attention to elements of safety, health, occupational safety and the environment (K3L) in accordance with applicable laws and regulations. It is hoped that by carrying out activities to monitor and control the radio frequency spectrum in the FM radio broadcast service in the DKI Jakarta service area, it can reduce the potential for harmful interference, so that all frequency users can utilize the frequency in an orderly, comfortable and safe manner from harmful frequency interference."

"Konstruksi fisik transformator terdiri atas elemen-elemen bersifat resistif, induktif, dan kapasitif, yang susunannya memiliki respon frekuensi yang khas.Dengan mengamati respon frekuensi suatu transformator, dapat dideteksi kerusakan mekanik yang terjadi pada inti dan belitan transformator tersebut. Metode yang sedang dikembangkan untuk mendeteksi kerusakan mekanik dikenal dengan Sweep Frequeency Response Analysis (SFRA). Proses pengukuran dilakukan dengan menginjeksikan sinyal tegangan rendah dengan menyapu nilai frekuensi mulai dari 20 Hz hingga 2 MHz. Dasar dari pengukuran ini merupakan analisis fungsi alih yang mana hasil pengukuran perlu diinterpretasikan lebih lanjut, salah satu caranya yaitu dengan perhitungan statistik. Indikator statistik yang digunakan yaitu koefisien korelasi, simpangan baku, dan absolute sum of logarithmic error (ASLE). Skripsi ini membahas proses interpretasi hasil pengukuran SFRA pada transformator 4 MVA, 11,8/6,3 kV di PT ABC dan transformator 12 MVA, 70/6,3 kV di PT XYZ menggunakan perhitungan statistik. Hasil yang didapat yaitu tidak ada indikasi kerusakan pada transformator 4 MVA, 11,8/6,3 kV di PT ABC pada kedua sisi kumparan. Sedangkan pada transformator 12 MVA di PT XYZ ditemukan indikasi kerusakan di bagian ujung (lead) kumparan utama dan tap kumparan pada kumparan tegangan 70 kV, dan di bagian inti, kumparan utama, tap kumparan, ujung (lead) kumparan utama, dan ujung (lead) tap kumparan pada kumparan tegangan 6,3 kV.

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Physical construction of transformerconsists of resistive, inductive, and capacitive elements,the structurehas a typical frequency response. By observing the frequency response of a transformer, we can detect mechanical damage that oK Kurs in the transformer core and windings. Method sare being developed to detect mechanical damage known as Sweep Frequeency Response Analysis (SFRA). Measurement processis done by injecting a low voltage signal with the sweep frequency values ranging from 20Hz to 2MHz. The basis of this measurement is transfer function analysis that the measurement results need to be interpreted further, one way is by statistical calculations. Statistical indicator that used is correlation coefficient, standard deviation, and sum of absolute logarith micerror (ASLE).

This thesis discusses the process of interpreting SFRA measurements result on PT ABC transformer, 4 MVA, 11,8/6,3 kV and PT XYZ transformer, 12 MVA, 70/6,3 kV using statistical calculations. The results are no indication of damage to PT ABC transformer, 4 MVA, 11,8/6,3 kV on both sides of the windings. While in PT XYZ transformer, 12 MVA found indications of damage at main and tap winding leads on 70 kV windings, and indications of damage at the core, main and tap windings, main and tap winding leads on 6,3 kV windings."