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"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...."

"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."

"Untuk pengiriman informasi yang bersifat rahasia diperlukan jaringan yang memiliki tingkat keamanan yang cukup tinggi, salah satu caranya dengan membangun Virtual Private Network (VPN). Pada teknologi VPN, aliran data di enkripsi untuk membungkus protokol-protokol jaringan serta dapat mengamankan jalur yang digunakan. Pada skripsi ini akan dibuat sistem bernama Hybrid VPN yang dirancang untuk menciptakan sebuah jaringan dengan tingkat keamanan cukup tinggi dengan menggabungkan dua buah metode VPN yang memiliki kelemahan dan kelebihan masing-masing. Untuk mengetahui performansi dari jaringan ini akan diukur beberapa parameter Quality of Service (QoS) untuk video streaming seperti throughput, delay, jitter, dan packet loss. Hasil Pengukuran membuktikan bahwa jaringan Hybrid VPN memiliki standar QoS yang baik untuk video dengan bitrate 1200 Kbps dengan nilai throughput sebesar 873.92 Kbps, Delay sebesar 40.51 ms, Jitter sebesar 59.62 ms, dan Packet Loss sebesar 12.62%.

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For delivering some confidential information, network must have a high level of security, such as implementing a Virtual Private Network (VPN). On VPN technology, the flow of data is encrypted to encapsulate network protocols and can be used to securing the path. A system called Hybrid VPN is designed to create a network with a high level of security by combining two methods of VPN that has the advantages and disadvantages each other. To determine the performance of these networks, it will be measured several parameters of Quality of Service (QoS) for video streaming such as throughput, delay, jitter, and packet loss. The results prove that the network with a Hybrid VPN has a good QoS for video streaming on 1200 Kbps of video bitrate with 873.92 Kbps of throughput, 40.51 ms of Delay, 59.62 ms of Jitter and 12.62% of Packet Loss."

"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."

"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."

"Salah satu tantangan utama dalam dunia telekomunikasi adalah menyediakan jasa Iayanan data berkecepatan tinggi. Kondisi keadaan pada saat ini, dengan teknologi broadband wireless yang ada dapat memberikan suatu cakupan area yang luas serta mampu dalam layanan data berkecepatan tinggi yang mengaplikaslkan multimedia.Salah salu upaya untuk menyediakan jasa layanan data berkecepatan tinggi adalah dengan melakukan teknik diversitas Dimana dalam hal ini adalah teknik diversitas yang dilakukan adalah teknik divertisitas ruang (Space diversity technique).Dalam tesis ini dilakukan simulasl teknik Space Time Block Coding (STBC) dan Space Frequency Block Coding (SFBC). Simulasi yang dilakukan adalah dengan memakai teknik pemancar tunggal clan pemancar ganda serta teknik penerima tunggal dan ganda.Hasil pengujian menunjukkan bahwa teknik space time coding dan space frequency block coding dengan memakai teknik pemancar dan penerima ganda memiliki perfomansi yang balk dibandinkan memakai teknik pemancar tunggal penerima ganda atau sebaliknya.

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One of the main challenge in telecommunication is to provide high speed data services. ln this recent condition, the broadband wireless technology could provide high scope coverage area and able to provide high speed data services using multimedia applications.One of the efforts to proved high speed data services is to diversity technique, which means that we use space diversity technique.ln this theses, we would use technique simulation space time block coding (STBC) and space frequency block coding (SFBC). ln this simulation we use single transmitter technique and multiple transmitter technique; we also use single receiver and multiple receiver technique.This test result showed that using double transmitter and receiver technique in space time block coding technique and space frequency block coding will have a better performance compare to using single transmitter technique multiple receiver or on the contrary."

"Dalam beberapa tahun ini, minat dalam pencapaian pengkodean suara toll-quality pada data laju kurang atau sama dengan 4 kbps makin meningkat. Penerapan speech coding yang semakin meluas, seperti pada jaringan nirkabel ketiga dalam sistem LEO (Low Earth Orbit), mendorong dilakukannya penelitian-penelitian. Kualitas pengkodean suara berbasis CELP (Code Excited Linier Prediction) menurun dengan cepat pada laju data 6 kbps, sehingga kurang sesuai untuk memenuhi kebutuhan tersebut. ITU (International Telecommunication Union) juga belum menetapkan standar pengkode suara untuk data 4 kbps dengan kualitas toll, sehingga penelitian di bidang ini masih terbuka. Salah satu kandidat pengkode suara untuk memenuhi kebutuhan di atas ialah Wave Interpolation Coder (WIC/Pengkode Interpolasi Gelombang). Pengkode ini pertama kali dikembangkan di AT&T pada tahun 80-an.Tujuan utama tesis ini ialah untuk meningkatkan kinerja pengkode WI dengan meningkatkan kineija pitch estimator. Pada tesis ini akan diujikan pitch estimator usulan yang dikembangkan dari pitch estimator rekornendasi ITU-T G.729 dan EVRC. Kinerja pengkode WI disimulasikan dengan menggunakan bahasapemprograman Matlab. Simulasi yang dilakukan meliputi pengukuran level SQNR, level segSNR dan rekonstruksi sinyal suara. Pada level SQNR didapatkan harga rata-rata negatip dan level segSNR menpunyai harga kurang dari 5 db , hal ini menunjukkan kinelja WIC lebih ditentukan oleh periodesitas sinyal. Rekonstruksi sinyal menunjukkan hasil yang lebih baik dengan menggunakan filter pitch. Hasil simulasi dengan menggunakan estimator pitch rata-rata menunjukkan peningkatan meskipun tidak signifikan.

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Recently the interest of speech code achievement of near-toll-quality at rates of 4 kbps or below increases. The application of speech coding, such as third generation wireless network and Low Earth Orbit (LEO) as well has encouraged the motivation research in this field. In fact, the Quality based on Code Excited Linear Prediction (CELP) ,decreasing at rates 6 kbps and not appropriate with this need. Speech coding standard for the rates of4 kbps and below hasn't obtained recommend ITU-T, and the research in this field is still open. One of the candidates to fulfill that Waveform Interpolation (WI) coder, the code was developed at the first time by AT & T in l980.The primary objective of this research is to increase of WI code by developing pitch estimator performance. In this research will test the proposed of pitch estimator which developed by from pitch estimator recommended by ITU-T G.729 and EVRC. Simulation performance WIC used MATLAB program, and will be measure SQNR level , segSNR level, and speech reconstruction is analyze. The result of SQNR level giving average negative value and segSNR level have less than 5 dB, this is proved that WIC performance more depend of signal periods not power level.Signal reconstruction used pitch estimator which proposed and pitch filter look more better than another both pitch estimator."