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Abstrak :
This paper presents new carrier-based and carrier-less ultra-wideband (UWB) transmitter architectures and their CMOS implementation. The carrier-based transmitter designed using a 0.18-?m CMOS process adopts a double-stage switching to enhance RF-power efficiency, reduce dc-power consumption and circuit complexity, and increase switching speed and isolation. Measurement results show that the generated UWB signal can vary from 2 V peak-to-peak with 3-dB 4-ns pulse width to 1 V with 0.5 ns, covering 10-dB signal bandwidths from 0.5 to 4 GHz, respectively. The generated UWB signal can be tuned to cover the entire UWB frequency range of 3.1 to 10.6 GHz. The carrier-less transmitter integrates tuning delay circuit, square-wave generator, impulse-forming circuit, and pulse-shaping circuit in a single chip using a standard low-cost 0.25-?m CMOS process. It can generate monocycle pulse and Gaussian-type impulse (without the pulse-shaping circuitry) signals with tunable pulse duration. Measured results show that the carrier-less transmitter can produce 0.3–0.6 V peak-to-peak monocycle pulse with 140–350 ps tunable pulse-duration and 0.5–1.3 V peak-to-peak impulse signal with 100–300 ps tunable pulse-duration.

Abstrak :
Sistem catu daya pada BTS mempunyai peran yang sangat penting pada perangkat telekomunikasi. Biasanya untuk BTS sebagai non prioritas dan transmisi radio sebagai prioritas. Operator seluler cenderung lebih memilih transmisi radio tetap berjalan walaupun ada gangguan atau padamnya listrik. Baterai menjadi pilihan untuk menggantikan catu daya. Namun, sistem catu daya PRS 1000 masih menggunakan satu keluaran baik itu untuk prioritas dan non prioritas. Bila beban yang diberikan semakin besar pada sistem, maka perangkat transmisi radio akan semakin cepat padam. Dengan menggunakan sistem DLVBD, keluaran sistem PRS 1000 menjadi dua, yaitu prioritas dan non prioritas. Pada saat sumber daya listrik mengalir, system DLVBD mendapat catu daya dan baterai mendapat catu dayanya masing - masing.Pada saat PLN padam, baterai melepaskan energi pada BTS dan radio sesuai dengan prioritasnya secara terpisah. Di saat beban BTS tidak bekerja karena LVBD1 terbuka, baterai radio tetap melepaskan energi sampai LVBD2 terbuka. Baterai BTS dapat mensuplai baterai radio jika tegangannya lebih besar dibandingkan dengan baterai radio, tetapi baterai radio tidak melakukan hal yang sama pada baterai BTS karena fungsi dioda sebagai pembatas arus. Hingga akhirnya LVBD2 terbuka saat tegangan baterai radio 43,20 V. Durasi waktu pelepasan baterai menjadi lebih lama bila dibandingkan dengan sistem PRS 1000 tanpa menggunakan sistem DLVBD. Pembahasan pada tugas akhir ini lebih ditekankan pada bagian pelepasan baterai pada beban, meliputi penjelasan mengenai aliran arus, perbandingan dengan sistem PRS 1000, dan perancangan perangkat keras dari sistem DLVBD. Selain itu, dijelaskan tentang cara kerja sistem dan pemanfaatan sistem PRS 1000 setelah dimodifikasi.

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Power supply system on BTS has a important task in telecommunication equipment. Usually for BTS as a non priority and radio transmission as a priority. Cellular operator disposed better choose radio transmission still working even there is a disturbing or no electricity. Battery become a choice for exchange power. However, power supply PRS 1000 still has one output for priority and non priority. If load more become greater to a system then radio transmission equipment more faster become off. With using DLVBD system, the output for PRS 1000 system becoming two, that is priority and non priority. At moment the energy from PLN is flowing trough the system, DLVBD system get a energy and battery get energy each other. At moment PLN off, battery discharge for BTS and radio appropriate with its priority on separate. At moment BTS load not working because LVBD1 open, radio battery still discharge till LVBD2 open. BTS battery can supply radio battery if the voltage bigger than radio battery, but radio battery don't do the same as BTS radio because diode function as a current limit. Until the end LVBD2 open when battery voltage at 43,20 V. Discharge backup time become longer than PRS 1000 system without using DLVBD system. Research for this final duty more pressing on discharge battery for load, include explanation about current flow, equivalent with PRS 1000 system, and hardware design for DLVBD system. Beside that, it explain about how the system work and benefit PRS 1000 system after modified.

Abstrak :
Paper ini membahas analisis throughput slotted ALOGHA DS-CDMA dengan dual model path gain kanal fadling nakagami dengan capture effect. pada peneltian ini BER yang digunakan pada S-ALOHA CDMA dengan dua model path gain yang berbeda pada kanal fadling nakagami/nakagami dengan capture effect.

Abstrak :
Metode Controlled Source Audio Frequency Magnetotelluric (CSAMT) memanfaatkan sumber buatan guna mendapatkan sinyal yang stabil dengan cara menginjeksikan arus dari transmitter dan diterima oleh receiver. Menggunakan frekuensi yang telah diatur yaitu frekuensi 6400 Hz - 2 Hz dengan target kedalaman > 1 km dan lama waktu pengukuran 30 menit pada setiap titik pengukuran. Hasil pengukuran yang didapat berupa medan magnet dan medan listrik yang ditangkap oleh receiver kemudian dengan persamaan Cagniard diperoleh nilai resistivitas semu. Pengukuran dilakukan di daerah ?A? dengan sistem hidrotermal tipe epitermal. Dari data lapangan dilakukan proses editing dan smoothing menggunakan software CMTpro kemudian dilakukan inversi menggunakan Bostik Inversion pada software MTSoft2D Penggunaan metode CSAMT ini didukung dengan metode geofisika lain seperti IP, resistivity, dan magnetik. Metode CSAMT dapat memberikan gambaran bawah permukaan dengan penetrasi yang lebih dalam zona penyebaran emas serta didukung metode IP, resistivity dan magnetik untuk mendapatkan korelasi pada kedalaman yang lebih dangkal. Hasil pengolahan ditampilkan secara 2D dengan software surfer 9 dan 3D dengan software Geoslicer-X. Terdapat korelasi hasil CSAMT dengan respon resistivitas > 350 Ohm.m pada kedalaman 400 meter serta diperkuat dari data pendukung metode resistivity dengan resistivitas > 350 Ohm.m dengan respon profil magnetik yang berundulasi, dan nilai PFE tinggi > 4%, yang merupakan zona silifikasi pada lintasan 8 dan 9.

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Controlled Source Audio Frequency Magnetotelluric (CSAMT) method is using an artificial to obtain a stable signal by injecting current from the transmitter and received by the receiver. Using preset frequency is 6400 Hz frequency - 2 Hz with a target depth of> 1 km and a long measurement time of 30 minutes, in each point of measurement. The measurement results obtained a magnetic field and electric field. and then use the equation Cagniard to get an apparent resistivity values. Measurements were taken in the area ?A? with type epithermal hydrothermal system. From the field data editing and smoothing process is carried out using software CMTpro. For the inversion is using a Bostik Inversion method with MTsoft2D. CSAMT method is supported by other geophysical methods such as IP, resistivity and megntic. CSAMT method can provide subsurface with a deeper penetration of the gold zone, supported method for distributing IP, resistivity and magnetic fields to obtain the correlation in the lower depth. The processing results is present in 2D with surfer 9 and 3D software with software Geoslicer-X. There is a correlation of results with a response CSAMT resistivity > 350 Ohm.m at a depth of 400 meters and reinforced the supporting data with the resistivity method resistivity > 350 Ohm.m with an undulation magnetic response profile, and high PFE values > 4%, which is a silicified zone on lines 8 and line 9.

Abstrak :
This practical resource offers a thorough examination of RF transceiver design for MIMO communications. Offering a practical view on MIMO wireless systems, this book extends fundamental concepts on classic wireless transceiver design techniques to MIMO transceivers. This in-depth volume describes many theoretical and implementation challenges on MIMO transceivers and provides the practical solutions for these issues. This comprehensive book provides thorough descriptions of MIMO theoretical concepts, MIMO single carrier and OFDM modulation, RF transceiver design concepts, power amplifier, MIMO transmitter design techniques and their RF impairments, MIMO receiver design methods, RF impairments study including nonlinearity, DC-offset, I/Q imbalance and phase noise and their compensation in OFDM and MIMO techniques.

Abstrak :
ABSTRAK
Power amplifier merupakan salah satu subsistem dalam rangkaian transmitter yang sangat penting. Power amplifier berfungsi untuk menaikkan daya dari sinyal yang akan dikirimkan sehingga sinyal masih mampu dideteksi oleh rangkaian penerima. Power Amplifier yang dirancang diperuntukan sebagai bagian dari sistem transmitter Indonesian Inter University Satellite (Iinusat). Iinusat merupakan sebuah satelit berkriteria nano yang dikembangkan oleh beberapa perguruan tinggi di Indonesia. Power amplifier yang akan dirancang didisain sehingga memiliki Maximum Available Gain (MAG) > 17 dB pada frekuensi downlink 436.9 MHz dengan faktor kestabilan (K) > 1. Selain itu, parameter yang juga harus diperhatikan dari perancangan power amplifier ini adalah nilai Voltage Standing Wave Ratio (VSWR) yang memiliki nilai 1≤VSWR≤1.2, dimana hal ini merepresentasikan banyaknya nilai sinyal terpantul. Pada kedua port power amplifier, baik input maupun output, diberikan rangkaian matching agar nilainya menjadi konjugasi dari nilai impedansi sistem untuk memaksimalkan daya yang mampu diteruskan oleh divais. Proses perancangan dilakukan dengan menggunakan piranti lunak advanced design system (ADS). Berdasarkan simulasi, hasil akhir rangkaian adalah bandwidth sebesar 1.5 MHz, faktor kestabilan 1.187, dan nilai VSWR sebesar 1.147.

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ABSTRACT
Power amplfier is one of many subsystems in transmitting circuitry which can be considered very important. Power amplifier can boost signal?s power up in order to be able to be transmitted in a quite long distance and still can be well detected by the receiver?s circuit. This Power amplifier is designed as a part of transmitter system in Indonesian Inter University Satellite (Iinusat). Iinusat is a nanosatellite built by several Indonesian universities. The designed power amplifier has maximum available gain (MAG) >17 dB and stability factor (K)>1. other parameter that is being considered in the design is the Voltage Standing Wave Ratio (VSWR), which the value is 1≤VSWR≤1.2. A making of microstrip line as a path of the signal and a connector between two components is required in this project to obtain a better result in designing the power amplifier subsystem. Both in the input and output port of this power amplifier, there are matching networks which are used as matching system so that the input and output port values are the conjugation of the system impedance. Advanced design system (ADS) is used in the designing process. The simulation yields bandwidth of the signal 1.5 MHz, stability factor 1.187, and the VSWR 1.147.

Abstrak :
This book discusses a number of challenges faced by designers of wireless receivers, given complications caused by the shrinking of electronic and mobile devices circuitry into ever-smaller sizes and the resulting complications on the manufacturability, production yield, and the end price of the products. The authors describe the impact of process technology on the performance of the end product and equip RF designers with countermeasures to cope with such problems. The mechanisms by which these problems arise are analyzed in detail and novel solutions are provided, including design guidelines for receivers with robustness to process variations and details of circuit blocks that obtain the required performance level.