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"We explore full-duplex technique in wireless communication particularly for relay networks. We consider the relay to operate in full-duplex, which transmission and reception are conducted in the same channel. We investigate potential benefits of full-duplex technique in relay networks, which uses multiple antennas for transmission and reception combined with Amplify-Forward (AF) scenario. We study the effects of multiple antennas in terms of relay capacity. We derive an ergodic capacity expression using Tracy-Widom distribution. Using Singular Value Decomposition (SVD) and perfect Channel State Information (CSI), we investigate three scenarios: First, we consider the relay to have antenna larger than that of both source and destination. Second, we consider both relay and destination to have antenna larger than that of source. Third, we consider both relay and source to have antenna larger than that of destination. We show the results that the capacity of relay with full-duplex technique is almost twice the capacity of half-duplex. We show that increasing the number of destination antennas is not help much when one of source antennas is small. Moreover, the capacity decreases due to channel hardening effect, when the number of destination antennas is larger than that of source."

"Efisiensi penggunaan sumber daya spektrum frekuensi yang terbatas merupakan target utama dari sistem komunikasi nirkabel. Keterbatasan spektrum frekuensi ini, telah mendorong para peneliti untuk mengembangkan komunikasi nirkabel full-duplex. Pada penelitian ini penulis mengusulkan skema optimasi penggunaan daya pada kanal MIMO full-duplex yang telah dilengkapi dengan teknik selfinterference cancellation pada domain propagasi.Pada penelitian ini diturunkan dan dianalisis persamaan mencari daya optimum dari sebuah kanal MIMO fullduplex yang akan menghasilkan kapasitas maksimum dengan menggunakan metode optimasi konveks. Berdasarkan hasil perhitungan terhadap kanal yang telah dioptimasi dapat dibuktikan bahwa kapasitas kanal meningkat sebesar 9 % pada penggunaan daya total sebesar 4 dB dan N=4 dibandingkan kapasitas kanal tanpa optimasi.

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Improving spectral efficiency driven by the limited frequency resources is a key target of the wireless communication system. The limitation of the frequency spectrum has led researchers to develop a full-duplex wireless communication. In this research, author proposes a power optimization scheme of full-duplex MIMO channel that has been equipped with self-interference cancellation techniques in the propagation domain.

In this research, by using convex optimization method, the expression of the optimum power scheme to achieve the maximum capacity of full-duplex MIMO channel is derived and analyzed. Calculation result shows that the capacity of the optimized channel increase 9 % at the total power 4 dB and N=4 compare with channel without optimization."

"ABSTRAKPada tugas akhir ini, saya menganalisa probabilitas outage dari teknologi full-duplex dengan menggunkan sistem MIMO (2x2) dengan memperhatikan faktor dari self-interference. Faktor self-interference pada tugas akhir ini diasumsikan telah ditekan dengan menggunakan active dan passive cancellation. Diasumsikan kanal yang dilalui sinyal antar 2 node merupakan kanal Rayleigh dan kanal yang dilalui sinyal interferensi merupakan kanal Rician. Selanjutnya, akan diperhatikan nilai dari probabilitas outage akibat dampak dari perubahan faktor K, 𝛾̅ɑ adalah SINR (Signal to Interference plus Noise Ratio), threshold rate (R) dan jumlah antena (N). Pada hasil perhitungan dengan nilai dari K = 35 dB atau lebih serta SINR = 70 dB dan R = 10 bps/Hz, probabilitas outage bernilai lebih dari 10-2 namun, dengan nilai SINR = 70 dB dan R = 10 bps/Hz, probabilitas outage bernilai lebih kecil dari 10-4 untuk nilai K = 15 dB atau kurang, maka didapat bahwa probabilitas outage meningkat jika nilai K meningkat. Selanjutnya, dengan nilai K = 10 dB didapat nilai dari probabilitas outage sebesar 10-4 ketika nilai SINR = 60 dB dan probabilitas outage sebesar 10-6 ketika nilai SINR = 70 dB, maka didapat probabilitas outage menurun jika nilai SINR meningkat. Hasil perhitungan lainnya dengan nilai K = 10 dB, didapat nilai dari probabilitas outage lebih dari 0,2 ketika nilai R = 6 bps/Hz dan probabilitas outage sebesar 0,8 ketika nilai R = 8 bps/Hz, didapatkan Probabilitas outage meningkat jika nilai R meningkat. Selanjutnya, dengan nilai K = 15 dB dan R = 20 bps/Hz, didapatkan nilai probabilitas outage sebesar 0,4, namun ketika nilai dari K = 15 dB dan R = 20 bps/Hz, nilai dari probabilitas outage dibawah 0,1, maka probabilitas outage menurun jika nilai N meningkat.

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ABSTRACTIn this report, I analyze an outage probability in bidirectional nirkabel communication using full-duplex MIMO system with consider effect of self-interference. The self-interference in this report is mitigated by active and passive cancellation, yet there is still interference happens in this system, called residual interference. Assumed, transmit information signal (channel between node-1 and node-2) using Rayleigh fading channel and express interference signal stream using Rician fading channel. I derive a closed-form solution of outage probability towards effect of Rician factor (K), γ̅ɑ is SINR (Signal to Interference plus Noise Ratio), threshold rate (R) and number of antenna (N). With SINR is 70 dB and R is 10 bps/Hz, value of outage probability is more than 10-2, yet with SINR is 70 dB and R is 10 bps/Hz, we get value of probability is below 10-2 for value of K is 15 dB or below, we obtain that value of outage probability increases when we increasing value of K. At value of K is 10 dB, we get outage probability is 10-4 when SINR is 60 dB and outage probability is 10-6 when SINR is 70 dB, from the result we conclude that for certain value of R, as SINR increases outage probability decreases for given K. Furthermore, at value of K is 10 dB, we get outage probability is more than 0.2 when R is 6 bps/Hz and outage probability is 0.8 when R is 8 bps/Hz. We get that as threshold rate increases outage probability increases for given SINR. Moreover, at value of K is 15 dB and R is 20 bps/Hz, we get outage probability is 0.4 but when value of K is 15 dB and R is 20 bps/Hz, we get outage probability is below 0.1. We obtain that increases number of antenna will decreases value of outage probability."

"Teknologi Full Duplex merupakan teknologi yang saat ini sedang berkembang karena mampu untuk meningkatkan transfer rate dan mendapatkan efisiensi spektral yang tinggi. Teknologi Full Duplex memungkinkan untuk menggunakan pita frekuensi yang sama untuk melakukan pengiriman sinyal informasi dan penerimaan sinyal informasi dalam waktu yang bersamaan, namun mode ini memiliki permasalahan yaitu, adanya self-interference antara antena pengirim dan penerima, yang mengakibatkan sinyal yang diterima pada antena penerima tidak hanya sinyal informasi dari sumber namun juga sinyal pengganggu yang berasal dari antena pengirim self-interference.Pada tugas akhir ini, saya menganalisa Probabilitas Sukses jaringan Full-Duplex dimana pada infrastruktur jaringan Full-Duplex disertakan relai. Relai disini berfungsi sebagai penguat sinyal, guna meminimalisir efek dari self-interference. Langkah awal penulis adalah memodelkan jaringan FullDuplex Relaying beserta dengan parameter-parameter yang mempengaruhinya. Kemudian memformulakan parameter tersebut ke dalam persamaan matematis menggunakan teknik Rayleigh Fading Assumption.Hasil dari formula ini kemudian dijabarkan ke dalam bentuk Probabilitas Sukses dengan batasan parameter pembanding threshold ? , noise n , dan jarak R . Langkah berikutnya memverifikasikan formula ke dalam simulasi Monte Carlo. Perbedaan metode Probabilitas Sukses dengan Monte Carlo terletak pada 2 hal, yang pertama pada Monte Carlo parameter random akan diubah-ubah nilainya, dalam hal ini adalah noise. Perbedaan kedua pada metode Monte Carlo dilakukan pengulangan simulasi, hal ini mengakibatkan grafik yang dihasilkan lebih presisi dibandingkan metode Probabilitas Sukses biasa. Dalam skripsi ini, penulis mensimulasikan metode Monte Carlo dengan pengulangan simulasi sebanyak 5000 kali.Hasilnya, penulis mendapatkan grafik probabilitas sukses dengan pola eksponensial, sesuai dengan persamaan matematis. Dimana probabilitas maksimum jaringan relai full-duple x nirkabel sebesar 0,7 pada saat threshold atau ? bernilai 0 dB.

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Full Duplex technology is a technology that is currently being developed for being able to increase the transfer rate and obtain high spectral efficiency. Full Duplex allows to use the same frequency band to perform signal transmission information and reception information signal at the same time, but this mode has a problem, namely, the self interference between the transmitting antenna and receiver, resulting in the received signal at the receiving antenna is not only signals from a source of information but also a bully signal originating from the transmitting antenna selfinterference.

In this report, I analyze success probability of Full Duplex network where the network infrastructure Full Duplex included relai. Relai here serves as a signal amplifier, in order to minimize the effects of self interference. The initial step is to model the Full Duplex Relaying network along with the parameters that influence it. Then formulated these parameters into a mathematical equation using the Rayleigh Fading Assumption technique.

The results of this formula are further described in the form Probability of Success with restrictions comparator threshold parameters, noise n, and distance R . The next step is describe the formula into Monte Carlo simulation. Difference methods between Monte Carlo and probability of success lies in two things, the first is in Monte Carlo random parameter value will be changed, in this case the noise. The second difference in the method of Monte Carlo simulation is there are repetition, this has resulted in the resulting graph is more precise than the usual method of Success Probability.

In this report, the authors simulate Monte Carlo method to simulate as much as 5000 times repetition.The result is, author get a success probability graph with exponential line, verified the formula. Where maximum success probability value of full duplex relaying wireless network is 0,7 when threshold or 0 dB. "

"Skema Multiple Input Multiple Output (MIMO) menjadi topik penelitian penting dalam bidang telekomunikasi nirkabel, karena memiliki kapasitas tinggi tanpa memerlukan tambahan bandwidth serta ketahanannya terhadap multipath fading. Permasalahan yang timbul pada MIMO adalah diperlukannya suatu skema agar setiap antena pemancar dapat digunakan untuk mengirimkan aliran data yang berbeda pada saat bersamaan, dan aliran data yang berbeda-beda tersebut dapat dipisahkan secara tepat di bagian penerima. Permasalahan lain pada sistem MIMO adalah pengkodean yang tepat untuk aliran data jamak sehingga data dapat diterima secara handal.Untuk mengatasi permasalahan tersebut, pada penelitian ini diajukan penggabungan arsitektur berlapis Vertical Bell Laboratories Space-Time Multiple Input Multiple Output (V-BLAST MIMO) serta pengkodean Rate Compatible Punctured Convolutional (RCPC). Penggunaan V-BLAST memungkinkan pengiriman data yang berbeda pada setiap antena, dan kode RCPC memberikan proteksi terhadap kesalahan kanal. Untuk mempermudah perhitungan parameter kode RCPC, digunakan kode konvolusional ekivalen. Kriteria Zero Forcing (ZF) dan Minimum Mean Squared Error (MMSE) digunakan untuk mengekstrak setiap sub-aliran informasi yang tiba di penerima.Penelitian ini menghasilkan kode RCPC menggunakan kode konvolusional ekivalen dengan periode puncturing Pc = 2 hingga 6, serta kode RCPC tanpa kode konvolusional ekivalen dengan periode puncturing Pc = 6. Hasil lainnya adalah persamaan BER untuk RCPC V-BLAST MIMO pada kanal fading Nakagami-m. Kanal fading Nakagami-m digunakan karena memiliki karakteristik empiris yang sesuai dengan pola fading secara general. Persamaan BER sistem dinyatakan dalam persamaan matematis yang modular, yang terdiri atas kinerja BER subsistem modulasi M-QAM multikanal, subsistem V-BLAST MIMO, dan subsistem RCPC dengan modulasi M-QAM dan kanal Nakagami-m.Simulasi numerik yang dilakukan menunjukkan bahwa peningkatan periode puncturing Pc akan meningkatkan jarak bebas kode dfree, sehingga memperbaiki BER sistem. Peningkatan dfree juga dapat dicapai dengan meletakkan bit yang di-puncture pada satu kolom dalam matriks puncturing, tanpa mengubah Pc. BER sistem juga akan semakin baik dengan penambahan jumlah antena, dimana penambahan jumlah antena penerima akan meningkatkan BER dengan lebih signifikan dibandingkan dengan penambahan jumlah antena pemancar. Semakin tinggi Pc yang digunakan, perbaikan BER yang dihasilkan oleh penambahan antena akan semakin kecil. Penggunaan deteksi berbasis MMSE akan meningkatkan BER sistem pada kisaran 0,5 hingga 1 dB dibandingkan deteksi berbasis ZF.

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The Multiple Input Multiple Output (MIMO) system has been the subject of rigorous research in the wireless telecommunication field, due to its ability to increase capacity without necessitating extra bandwidth and its robustness against multipath fading. There are two main problems arising in this system. The first is the need to find a scheme to send different information symbols simultaneously using multiple transmit antennas, as well as enabling the extraction of those symbols in the receiver. The second problem is finding a correct coding type for multiple information streams to provide robustness against channel errors.

To solve these problems, this research proposes the integration of Vertical Bell Laboratories Space-Time Multiple Input Multiple Output (V-BLAST MIMO) scheme and Rate Compatible Punctured Convolutional (RCPC) encoding. The use of V-BLAST scheme will enable the transmission of different data streams simultaneously using the multiple transmit antennas, while RCPC codes protect the data against channel errors. To simplify the calculation of RCPC code parameters, equivalent convolutional codes are used. Zero Forcing (ZF) and Minimum Mean Squared Error (MMSE) criteria are used to extract the different data streams arriving in the receiver.

In this research RCPC codes using equivalent convolutional codes which puncturing periods are Pc = 2 to 6, and an RCPC code without equivalent convolutional code which Pc = 6 are obtained. A mathematical formulation of BER for RCPC V-BLAST in Nakagami-m fading channel is derived and numerically simulated. The Nakagami-m model is used as its empirical characteristics match those of general fading pattern. The mathematical BER of the system is stated as a modular equation, consisting of the subsystems BER.

The numerical simulations results show that the increase of Pc will increase the free distance of the codes dfree, which in turn will increase the system BER. The increase of dfree can also be obtained by placing the punctured bits in one column of the puncturing matrix, without changing the Pc. Increasing the number of antennas will also improve the system BER. The increased number of receive antennas will contribute more significantly to the BER improvement compared to the increase of transmit antennas. The larger the Pc used, the BER improvement yielded by increasing the antenna numbers will be more insignificant. The use of MMSE-based detection will improve the system BER by 0.5-1 dB compared to the ZF-based detection."

"This book covers the design and optimization of hybrid RF-baseband precoding for massive multiple-input multiple-output (MIMO)-enabled cloud radio access networks (RANs), where use cases such as millimeter-wave wireless backhauling, fully-loaded cellular networks are of interest. The suitability and practical implementation of the proposed precoding solutions for the Cloud RAN architecture are also discussed.Novel techniques are examined for RF precoding optimization in combination with nonlinear precoding at baseband, and the superiority of joint RF-baseband design is verified. Moreover, the efficacy of hybrid RF-baseband precoding to combat intercell interference in a multi-cell environment with universal frequency reuse is investigated, which is concluded to be a promising enabler for the dense deployment of base stations. This book mainly targets researchers and engineers interested in the challenges, optimization, and implementation of massive MIMO precoding in 5G Cloud RAN. Graduate students in electrical engineering and computer science interested in the application of mathematical optimization to model and solve precoding problems in massive MIMO cellular systems will also be interested in this book."

"A combination between MIMO (Multiple-input multiple-output) and OFDM is expected to become a solution to increase data rate in wireless communication...."

"Skripsi ini membahas mengenai serangan Man in the Middle yang dikombinasikan dengan SSLstrip. Tipe serangan ini adalah jenis serangan yang hanya bisa dilakukan dalam satu jaringan dengan korbannya. Serangan ini secara umum bertujuan untuk mengambil data-data penting dari korbannya, seperti username, password, dan data-data penting lainnya yang bersifat rahasia. Metode serangan ini tentu sangat berbahanya mengingat data-data yang diambil sifatnya sangatlah penting. Analisis serangan MitM dan SSLstrip dilakukan untuk mengetahui tingkat bahaya dari serangan ini. Variasi-variasi skenario dilakukan untuk mengetahui secara detail teknik serangan ini. Dari hasil penelitian ini didapatkan bahwa untuk melakukan serangan ini tidak dibutuhkan spesifikasi komputer yang tinggi. Hanya dibutuhkan waktu kurang dari 0.2 detik dampak sudah bisa dirasakan oleh target. Akibat dari serangan ini adalah meningkatnya waktu yang dibutuhkan untuk mengakses halaman web. Terjadi peningkatan waktu hingga sebesar 381,7 % ketika penyerangan terjadi.

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This final project discussing about Man in the Middle attack combined with SSLstrip. The type of the attack only can be done in the same network with the victim. Generally this attack is intended to steal any important data from the victim, like username, password and the other important datas. The kind of the attack is absolutely dangerous because the purpose its self is for stealing the privacy of the victim. Analysis MitM attack and SSLStrip conducted to determine the danger level of these attacks. Variations scenarios conducted to determine the details of this attack technique. From the results of this study found that this attack is not high specification computer needed. It took less than 0.2 second impact could be felt by the target. The result of this attack is the increased time needed to access web pages. An increase of time up to 381.7% when the attack occurred."

"Channel estimation memiliki definisi untuk memperkirakan koefisien filter melalui sinyal yang diterima dan informasi lain yang dikenal. Ada beberapa metode channel estimation yang dapat diguanakan seperti minimum mean square error, least square, zero-force, maximum likelihood. Dalam penelitian ini, least square dan zero-force akan dibahas lebih lanjut. Kedua jenis ini dikenal umum sebagai jenis yang paling sederhana dan paling mudah untuk diterapkan di dalam komunikasi nirkabel. Meskipun metode lain seperti minimum mean square error atau maximum likelihood telah dikenal secara luas untuk memperkirakan kanal, metode tersebut terbukti sangat kompleks untuk diimplementasikan.Penelitian ini bertujuan untuk memahami efek dan membandingkan kinerja channel estimation dengan menggunakan kapasitas multi antenna seperti Single-Input Single Output (SISO), Multiple-Input Single-Output (MISO), Single-Input Multiple-Output (SIMO) dan Multiple-Input Multiple-Output (MIMO). Least square dan metode estimasi zero-force telah digunakan dengan memakai modulasi Binary Phase Shift Keying (BPSK), hal ini dikarenakan BPSK adalah metode phase shift keying yang paling sederhana untuk di implementasikan di dalam penelitian ini. Pertama-tama, segala parameter perlu dikonfigurasi terlebih dahulu untuk digunakan di dalam simulasi. Kemudian, data dalam sistem pilot dikirim ke penerima menggunakan modulasi BPSK di setiap sistem multi antenna dengan menggunakan saluran nirkabel yang berbeda. Lalu, Alamouti encoder dieksekusi khusus untuk sistem MIMO dan MISO. Setelah itu, least square dan zero-force diterapkan dan tingkat kesalahan bit atau dengan nama lain bit error rate (BER) dapat dicapai dengan menyamakan sinyal yang ditransmisikan. Kemudian, analisa hasil data dengan membandingkan kinerja least square dan zero-force dapat dicapai. Pada akhirnya, hasil yang telah ditemukan menunjukkan bahwa least square melakukan performa lebih baik daripada metode estimasi zero force yang berlaku pada kinerja tingkat kesalahan bit dengan sinyal terhadap noise atau dengan nama lain signal to noise ratio (SNR).

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Channel estimation has a definition to estimate the filter coefficient through received signal and other known information. There are many methods that channel estimation can be used such as minimum mean square error, least square, zero-force, maximum likelihood. In this research, least square and zero force will be discussed further. These two types are commonly known as the simplest and easiest type to implement in the wireless communication. Even though other methods like minimum mean square error or maximum likelihood have been widely known to estimate channel, such methods are proven very complex to implement.

The aimed of this research is to understand the effect and compare the performance of the channel estimation method with the capacity of multiple antennas such as Single-Input Single-Output (SISO), Multiple-Input Single-Output (MISO), Single-Input Multiple-Output (SIMO) and Multiple-Input Multiple-Output (MIMO). Least square and zero force estimation method were being used with BPSK modulation, this is due to BPSK is the simplest phase shift keying.

First, the parameters need to be configured in simulation software. Then, the data within pilots system transmitted to receiver using BPSK modulation in each of the wireless antenna systems with different wireless channels. Space time block coding of Alamouti encoder were executed for MIMO and MISO system. After that, least square and zero force method were implemented and bit error rate (BER) performance can be achieved by equalizing the transmitted signal. Analysing the result by comparing the performance of least square and zero force were accomplished.

In the recent result, it was shown that the least square performs better than zero force estimation method for the performance of bit error rate with signal to noise ratio."