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"Cognitive radio merupakan teknologi telekomunikasi yang memberikan solusi untuk masalah keterbatasan ketersediaan sumber daya spektrum frekuensi dan rendahnya efisiensi penggunaan spektrum yang ada. Skripsi ini membahas rancang bangun antena yang sesuai untuk aplikasi cognitive radio yang dapat digunakan pada alokasi frekuensi 1,8 GHz dan 2,35 GHz. Rancang bangun antena terdiri dari dua antena printed monopole di atas substrat FR4 dengan menggunakan ground sebagian. Antena pertama berfungsi sebagai sensing antenna dengan karakteristik wideband dan memiliki pola radiasi omnidirectional. Antena kedua merupakan communicating antenna dimana pada struktur antena diberi switch sehingga antena ini dapat merekonfigurasi frekuensi kerja. Hasil pengukuran menunjukkan sensing antenna memiliki impedance bandwidth 5,197 GHz pada kondisi switch OFF dan impedance bandwidth 10,328 GHz pada kondisi switch ON yang diukur pada batas RL ≤ -10 dB. Sedangkan reconfigurable communicating antenna memiliki frekuensi kerja 2,35 GHz pada kondisi switch OFF dan frekuensi kerja 1,8 GHz pada kondisi switch ON.

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Cognitive radio is technology developed nowadays to be the solution for limited frequency spectrum resource and inefficiency spectrum utilization issues. Design of antenna for cognitive radio application is proposed in this final project. The antenna is designed to work at 1.8 GHz and 2.35 GHz frequency allocation. The design consists of two printed monopole antenna printed over FR4 substrate sharing a common partial ground. The first antenna is the sensing antenna for spectrum sensing, having wideband characteristic and omnidirectional radiation pattern. The second one is the communicating antenna which is a frequency reconfigurable antenna with the existing switch on the antenna's structure so that the antenna will have two different working frequencies. The measurement shows that the sensing antenna has 5.197 GHz impedance bandwidth when the switch is OFF and 10.328 GHz impedance bandwidth when the switch is ON which is measured at return loss below -10 dB. While, the reconfigurable communicating antenna is working at 2.35 GHz when the switch is OFF and it is working at 1.8 GHz when the switch is ON."

"Cognitive radio merupakan teknologi telekomunikasi yang sedang dikembangkan dalam rangka mengatasi terbatasnya sumber daya spektrum frekuensi dan rendahnya efisiensi penggunaan spektrum yang ada. Skripsi ini membahas rancang bangun antena yang sesuai untuk aplikasi cognitive radio yang dapat bekerja pada frekuensi CDMA 1,9 GHz , WCDMA 2,1 GHz dan WiMAX 2,3 GHz untuk divais elektronik. Rancang bangun antena terdiri dari dua antena yaitu printed monopole antenna untuk pemindai dan Z-shape slot microstrip antenna untuk reconfigurable antenna. Dua antena tersebut di fabrikasi pada substrat FR4 dengan ground yang umum pada lapisan atasnya. Antena pemindai bertujuan sebagai pemindai spektrum dengan karakteristik pita lebar (1,0 GHz sampai 2,4 GHz). Reconfigurable antenna bertujuan untuk menghasilkan frekuensi resonansi dengan mengatur switch pada antenna yang memungkinkan antena memiliki tiga frekuensi resonansi yang berbeda. Hasil pengukuran menunjukkan sensing antenna memiliki impedance bandwidth 1,4 GHz (VSWR ≤ 2) dengan pola radiasi yang baik jika dibandingkan dengan hasil simulasi. Sedangkan reconfigurable antenna dapat bekerja dengan baik CDMA 1,9 GHz , WCDMA 2,1 GHz dan WiMAX 2,3 GHz sebagai prediksi pada hasil simulasi.

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Cognitive radio is technology that is developed as a solution for limited frequency spectrum resources and inefficiency spectrum utilization issues. This thesis discusses the design of antenna for cognitive radio applications applied into electronic device which can perform at CDMA, WCDMA and WiMAX frequency.

The design consists of two antennas, namely a printed monopole antenna for sensing and Z-shape slot microstrip antenna for reconfigurable antenna. Two antennas are fabricated on FR4 substrate with common ground on the top layer.

The sensing antenna is aimed at spectrum sensing, which has wideband characteristics (1.0 GHz to 2.4 GHz) and omnidirectional radiation pattern. The reconfigurable antenna is designed for generating the desired resonant frequency by adjusting the switch position on the antenna structure allowing for the antenna to have three different resonant frequencies.

The measurement results show that the sensing antenna has 1.4 GHz impedance bandwidth (VSWR ≤ 2) with good agreement of the radiation pattern compared to the simulation results. Moreover, reconfigurable antenna can work well at CDMA 1.9 GHz, WCDMA 2.1 GHz dan WiMAX 2.3 GHz as predicted in the simulation results."

"This book provides the most up-to-date research advances and theories in cognitive radio technology, from cognitive radio principles and theory to cognitive radio standards and systems, from fundamental limits of cognitive radio channels to cognitive radio networks, from the current cognitive radio practices and examples to future 5G cognitive cellular networks. The book will include some emerging applications of cognitive radio in areas such as smart grid, internet-of-things, big data, small cell/heterogeneous networks, and in 5G. The potential readers include postgraduate students, academic staff, telecommunications engineering, spectrum policy makers, and industry entrepreneurs."

"Cognitive radio networks (CRN) will be widely deployed in the near future, and this SpringerBrief covers some important aspects of it, as well as highlighting optimization strategies in Resource Allocation and Spectrum Sensing in CRNs. The cognitive approach in radio access is introduced in the first part of this SpringerBrief, and then next the benefits of cooperative spectrum sensing are highlighted and a framework for studying it under realistic channel conditions is described. New exact closed-form expressions for average false alarm probability and average detection probability are derived in this scenario. A novel approximation to alleviate the computational complexity of the proposed models are also discussed.Once the spectrum opportunities are identified, efficient and systematic resource allocation (RA) shall be performed. The second part of this SpringerBrief describes the taxonomy for the RA process in CRN. A comprehensive overview of the optimization strategies of the CRN RA is also provided. The device-to-device (D2D) communication scenario is discussed, then as a case study and various optimization strategies for the application of the CR technology in the D2D realm is studied. The application of advanced geometric water-filling (GWF) approach in CRN D2D environment for optimum resource allocation is presented in detail. Numerical results provide more insight quantitatively. Overall, this book is suitable for a wide audience that include students, faculty and researchers in wireless communication area and professionals in the wireless service industry."

"This major reference work provides the most up-to-date research advances and theories in cognitive radio technology, from cognitive radio principles and theory to cognitive radio standards and systems, from fundamental limits of cognitive radio channels to cognitive radio networks, from the current cognitive radio practices and examples to future 5G cognitive cellular networks. This handbook will include some emerging applications of cognitive radio in areas such as smart grid, internet-of-things, big data, small cell/heterogeneous networks, and in 5G. The potential readers include postgraduate students, academic staff, telecommunications engineering, spectrum policy makers, and industry entrepreneurs."

"Skripsi ini membahas rancang bangun antena reconfigurable untuk aplikasi cognitive radio pada alokasi spektrum 1,8 GHz, 2,1 GHz uplink, 2,1 GHz downlink, dan 2,35 GHz. Rancang bangun antena terdiri dari dua antena yaitu antena sensing dan antena communicating yang digabungkan dalam satu divais. Antena sensing memiliki karakteristik ultrawideband dari 1,65 GHz - 3,75 GHz (bandwidth = 2,1 GHz) dan antena communicating memiliki karakteristik narrowband pada frekuensi 1.8 GHz, 2.1 GHz uplink, 2.1 GHz downlink, dan 2.35 GHz. Hasil validasi dengan pengukuran diperoleh hasil yang sesuai dengan rancangan simulasi, terutama meliputi parameter return loss, pola radiasi, dan gain.

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This bachelor thesis discusses a design and fabrication of reconfigurable antenna for cognitive radio applications, especially for allocation of spectrum 1.8 GHz, 2.1 GHz Uplink, 2.1 GHz Downlink, and 2.35 GHz. The antenna design consists of two antennas which sensing antenna and communicating antenna. The sensing antenna has ultrawideband characteristics from 1.65 GHz - 3.75 GHz (the bandwidth about 2.1 GHz) and the communicating antenna has narrowband characteristics at the center frequency 1.8 GHz, 2.1 GHz uplink, 2.1 GHz downlink, and 2.35 GHz. The validation has been conducted by the measurement, where it agrees with the simulation result, in particular for the parameter of return loss, radiation pattern and gain of the antenna."

"This book provides a broad introduction to Cognitive radio, which attempts to mimic human cognition and reasoning applied to software defined radio and reconfigurable radio over wireless networks. It provides readers with significant technical and practical insights into different aspects of Cognitive radio, starting from a basic background, the principle behind the technology, the inter-related technologies and application to cellular and vehicular networks, the technical challenges, implementation and future trends. The discussion balances theoretical concepts and practical implementation. Wherever feasible, the different concepts explained are linked to application of the corresponding scheme in a particular wireless standard."

"Radio-Frequency Identification (RFID) telah menjadi salah satu segmen teknologi yang memiliki pertumbuhan pesat pada industri pengumpulan data dan identifikasi otomatis. Salah satu bagian terpenting dari sistem RFID adalah power amplifier yang memungkinkan terjadinya transfer daya antara reader dengan transponder untuk melakukan identifikasi. Pada penelitian ini diusulkan power amplifier kelas E untuk aplikasi RFID yang bekerja pada frekuensi 13.56 MHz. Power amplifier pertama kali disimulasikan dengan menggunakan software Advance Desain System (ADS) dan kemudian hasil simulasi difabrikasi. Power amplifier kelas E yang dirancang memiliki kestabilan K sebesar 1.758, return loss masukan (S11) sebesar -23.587 dB, return loss keluaran (S22) sebesar -19.123 dB, gain (S21) sebesar 22.742 dB, VSWR sebesar 1.142, dan PAE maksimal 79.331% pada frekuensi 13.56 MHz. Sedangkan power amplifier hasil fabrikasi memiliki performansi yang cukup berbeda dengan hasil simulasi dimana hasil fabrikasi memiliki return loss masukan (S11) sebesar -14.926 dB, return loss keluaran (S22) sebesar -12.812 dB, dan gain (S21) sebesar 0.852 pada frekuensi 13.56 MHz.

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Radio-Frequency Identification (RFID) has become a technology segment that growth rapidly in data collecting industry and automatic identification. One of the most important part of RFID system is power amplifier that enable power transfer between reader and transponder for identification purpose.

This research propose power amplifier class E for RFID application at 13.56 MHz frequency’s. The power amplifier is simulated with Advanced Design System (ADS) software then the simulation design is fabricated.

The simulation result of class E power amplifier has stability factor K of 1.758, input return loss (S11) of -23.587 dB, output return loss (S22) of -19.123 dB, gain (S21) of 22.472 dB, VSWR of 1.142, and maximum PAE of 79.331% on frequency of 13.56 MHz.

The fabrication result of power amplifier has a difference performance to the simulation result where the fabrication result has input return loss (S11) of -14.926 dB, output return loss (S22) of -14.926 dB, gain (S21) of 0.852 dB on frequency of 13.56 MHz."

"Gelombang radio dapat sampai ke penerima dengan cara langsung, merambat dekat permukaan bumi, dan melalui pemantulan ionosfer. Cara perambatan yang terakhir inilah yang digunakan untuk komunikasi jarak jauh, menggunakan frekuensi tinggi (HF: 3 – 30 MHz), dengan memanfaatkan pemantulan lapisan ionosfer. Antena yang umum digunakan dalam komunikasi radio HF adalah antena dipole setengah panjang gelombang (½ λ). Tiga komponen yang menentukan keberhasilan komunikasi dengan gelombang antariksa adalah frekuensi, sudut elevasi, dan daya pancar. Frekuensi berkaitan dengan kerapatan elektron di lapisan ionosfer, sudut elevasi ditentukan oleh jarak komunikasi dan ketinggian lapisan ionosfer, dan menentukan ke arah mana gelombang radio harus dipancarkan, sedangkan daya pancar menunjukkan besarnya energi gelombang radio yang dipancarkan. Ketinggian antena menentukan pola radiasinya, yaitu distribusi energi gelombang radio yang dipancarkan, oleh karena itu berperan dalam menentukan sampainya gelombang radio di tujuan komunikasi."