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"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."

"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."

"Penelitian ini bertujuan untuk mendesain dan menganalisa unjuk kerja trellis coded TC 2 x 4PSK pada kanal fading Nakagami. Desain kode TC multidimensi dilakukan berdasarkan konsep trellis coded modulation pada kanal fading yaitu dengan memperbesar effective code length (ECL) dan product of distance (PD). Untuk mendapatkan performansi yang lebih baik, dilakukan pemilihan kode-kode sinyal dari kombinasi kode yang ada untuk meminimalkan korelasi dari pasangan kode sinyal sehingga diperoleh independensi. Pemilihan kode sinyal dilakukan dengan memilih 8 dari 16 kombinasi pasangan kode sinyal yang mempunyai jarak Euclidean yang lebih besar. Analisa performansi TCM multidimensi pada kanal fading dilihat dari besarnya Probabilitas Error (Pe) yang terjadi. Hasil penelitian memperlihatkan bahwa TC 2 x 4PSK dengan pemilihan pasangan kode sinyal (expurgated phase code) mempunyai unjuk kerja BER yang lebih baik dari TC 2 x 4PSK bila seluruh pasangan kode sinyal digunakan (full code) baik pada A WGN maupun pada kanal fading Nakagami. Penerapan TC 2 x 4PSK dengan expurgated phase code memberikan coding gain sebesar 0,125 dB pada AWGN serta meningkatkan performansi sebesar 4 dB pada kanal fading Nakagami untuk m = 2 pada BER = w-5 , dibandingkan dengan TC 2 X 4PSK denganfull code.

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The purpose of this theses is to design and analize the performance of trellis coded TC 2 x 4PSK on Nakagami fading channel. The code design is based on maximizing the effective code length (ECL) and product of distance (PD). To give better performance, expurgated phase code is used instead of complete code by selecting 8 from all 16 code combinations which have larger Euclidean distance to minimize the maximum correlation between any pair of signals. BER performance TC 2 x 4PSK with expurgated phase code on Nakagami fading channel for various Nakagami fading pameters m are calculated and analized. The result shows that TC 2 x 4PSK with expurgated phase code gives better performance than TC 2 x 4PSK with full code on both A WGN and Nakagami fading channel. It is shown that by using TC 2 x 4PSK with expurgated phase code, coding gain is achieved 0.125 dB in A WGN and gives performance improvement 4 dB in Nakagami fading channel, compared to TC 2 x 4PSK with full code. As comparison, the BER performance of TC QPSK and TC 8PSK are also presented."

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

"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."

"The book presents a comprehensive view of channel degradation arising from fading and shadowing. Various statistical models including simple, hybrid, compound, complex and cascaded ones are presented with detailed derivations along with measures to quantify the deterioration such as the amount of fading, error rates and outage probabilities. The models range from the Rayleigh and Rician through Suzuki, generalized K, cascaded and alpha-mu and similar ones. This is followed by the analysis of mitigation of fading and shadowing through diversity (simple, hybrid, micro- and macro- level) and combining algorithms. The density and distribution functions, error rates and outages are derived and results analyzed to quantify the improvements. The effects of co-channel interference before and after the implementation of diversity are also analyzed. To facilitate easy understanding of the models and analysis, the background information in terms of probability and random variables is presented with relevant derivations of densities of linear and nonlinear transformation of random variables, the sums, products, ratios as well as order statistics of random variables of all types. The book also provides material on digital modems of interest in wireless systems. Thus, the book with 1100+ equations and 350+ Matlab generated figures and tables is an ideal source for students, educators, researchers and professionals in wireless communications allowing access to information currently unavailable."

"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."

"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."

"Konsep Orthogonal Frequency Division Multiplexing ( OFDM) adalah membagi aliran data input serial ke dalam sejumlah aliran data paralel dan mengirimkan aliran data paralel dengan rate rendah tersebut secara bersamaan. Salah satu keuntungan penggunaan OFDM dibandingkan dengan jenis modulasi lain adalah penggunaan lebar pita yang tersedia dengan lebih efisien.Simulasi dan analisa dilakukan terhadap performansi sistem OFDM pada beberapa mapper modulasi 16-my pada kondisi kanal AWGN dan kanal fading lambat. Jenis konstelasi yang digunakan adalah 16-QAM rektangular, 16-QAM star dan 16-PSK.Hasil pada kondisi kanal AWGN memperlihatkan bahwa sistem OFDM yang menggunakan 16-QAM rektangular memberikan performansi BER terbaik dibandingkan penggunaan 16-QAM star atau 16-PSK.Performansi OFDM pada kanal fading multipath dianalisa menggunakan respons impuls kanal statik. Hasil pada kedua model kanal fading multipath yang digunakan menunjukkan performansi yang relatif buruk. Algoritma forward error correction atau estimasi kanal perlu digunakan untuk mengurangi probabilitas kesalahan bit.Hasil akhir pada penggunaan kedua algoritma tersebut membuktikan bahwa pengaruh fading kanal multipath dapat dihilangkan sehingga meningkatkan performansi BER sistem OFDM.

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The concept of OFDM is to divide the serial input data stream into a number of parallel streams and to transmit these low-rate parallel streams simultaneously. One advantage of using OFDM compared to other types of modulation is better use of the available bandwidth.

The performance of the OFDM system under various 16-ary modulation mappers in AWGN and slowly fading channels are analyzed. It considers three candidate constellations : 16 rectangular-QAM, 16 star-QAM and 16-PSK.

The results for AWGN channel shows that the OFDM system using 16 rectangular-QAM gives the best BER performance compared to the same system using 16 star-QAM or 16-PSK mapper.

The performance of OFDM on multipath fading channels is analyzed using static channel impulse responses. The results of system in the two models of multipath fading channels indicate a relatively poor performance. Forward error-correcting or channel estimation algorithm is necessary to reduce the bit error probability.

The final results obtained after the use of both algorithms : convolutional coding and channel estimation, prove that fading effects can be removed, reducing almost totally the effects of the multipath channel."

"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."