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"Multiplexing is meant to record a number of different information in a piece of film. The multiplexing is conducted by giving a code to each information prior to the recording. In this research the multiplexing is done with the theta modulation technique, i.e. using a rotated grating so that each information is coded by a certain angular direction of the spatial frequency of the grating. To recover the original information, the demultiplexing is done by filtering the Fourier transform of the multiplexed recording. A spatial filter in the form of a properly oriented slit is located at the Fourier plane to transmit the diffraction pattern of a single information. The limitations to the number of information which could be recorded are the information extent within each object and the linearity characteristics of the film used. The experiment has been conducted using a diffraction grating with a spatial frequency of 14.2 lp/mm. For an exposure speed of 1/1000 second for each information and a grating rotation angle of 1.50, a number of eleven (11) information can be multiplexed. For an exposure speed of 1/2000 second, and a grating rotation angle of 50, eighteen (18) information can be multiplexed."

"Sinyal yang diterima dari kanal komunikasi dengan modulasi M-QAM dapat berubah karena munculnya sejumlah bit yang salah (error). penyebab terjadinya bit error dapat berupa interferensi, seperti Rayleigh fading serta noise, seperti additive white gaussian noise (AWGN). pengurangan bit error pada modulasi M-QAM dapat digunakan dengan teknik spatial multiplexing disisi pengirim dan metode pendeteksian dan penerimaan sinyal di sisi penerima. terdapat beberapa penelitian yang dilakukan sebelumnya mengenai penerapan spatial multiplexing di sisi pengirim dan metode pendeteksian dan penerimaan sinyal di sisi penerima, seperti penelitian pada komunikasi CDMA dengan metode OSIC, ZF dan Maximum Likelihood. selain itu, terdapat penelitian tentang MMSE dan penelitian mengenai penerapan metode ZF-SIC pada modulasi BPSK. Permasalahan yang kemudian dihadapi dan menjadi pokok bahasan dalam penulisan tesis ini adalah bagaimana memaksimalkan pengurangan bit error hingga 10-4 atau mendekati 0 agar sinyal yang diterima dapat Mediterranean kembali dengan benar. untuk itu dalam tesis ini diusulkan penggunaan teknik spatial multiplexing dengan metode pembatalan atau penekanan terus menerus sinyal interferensi yang terdapat pada sinyal yang diterima yang diistilahkan dengan succesisive interference cancellation (SIC) pada metode ZF, MMSE, dan maximum likelihood serta lebih dimaksimalkan dengan menambahkan metode pemilihan sinyal gangguan terberat MRC.

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The signal received from the communication channel with M-QAM modulation can change due to the appearance of a number of wrong bits (error). the cause of bit error can be interference, such as Rayleigh fading and noise, such as additive white gaussian noise (AWGN). bit error reduction in M-QAM modulation can be used with the spatial multiplexing technique on the sending side and the method of detecting and receiving signals on the receiving side. There have been several studies conducted previously regarding the application of spatial multiplexing on the sending side and the method of detecting and receiving signals on the receiving side, such as research on CDMA communication with OSIC, ZF and Maximum Likelihood methods. In addition, there are research on MMSE and research on the application of the ZF-SIC method on BPSK modulation.

The problem that is then faced and the subject of the discussion in writing this thesis is how to maximize the reduction of bit error up to 10-4 or close to 0 so that the signal received by Mediterranean can return correctly. Therefore, this thesis proposes the use of spatial multiplexing techniques by continuously canceling or suppressing the interference signals found on signals received which are termed as successful interference cancellation (SIC) in the ZF, MMSE, and maximum likelihood methods and more maximized by adding selection methods. MRC's heaviest signal interference."

"OFDM (Orthogonal Frequency Division Multiplexing) adalah suatu teknik multicarrier, dimana membagi spektrum dalam beberapa pembawa. OFDM merupakan bentuk khusus dari Frequency Division Multiplexing (FDM), yang menggunakan spektrum lebih kecil dan terbagi ke dalam beberapa pembawa dengan mengambil jarak antar Frekuensi yang bersebelahan, sehingga penggunaan bandwidth akan lebih efektif OFDM memiliki efisiensi pada pemakaian frekuensi yang jauh lebih baik dibanding dengan teknik FDM (Frequency Division Multnnlexing) multicarrier biasa, akan tetapi OFDM juga tidak lepas dari interferensi yaitu phase error dan ICI (Inter- carrier Interference). Hal ini dapat mengakibatkan penurunan pada QoS (Quality Service Support) dalam sistem OFDM.Metoda perhitungan EKF (Extended Kalman Filtering) adalah metoda yang dapat dipergmmakan pada sistem Iinier dan non-Iinier, sehingga metoda ini merupakan suatu implementasi yang kompleks dengan penggunaan yang sederhana. Metoda extended kalman filter juga memiliki basil pengukuran yang lebih baik dibanding metoda seMcanceIlation dan ML-estimation. Pada perhitungan jrequency ojket dari penerimaan suatu sinyal, extended kalman filter memiliki performansi yang baik dalam memperoleh perhitungan yang cepat. Sehingga dengan penggunaan metoda extended kalman fitter akan mengurangi ICI (Inter-carrier Intewrence) pada suatu sistem OFDM (Orthogonal Frequency Division Mulmvlexing).Tesis ini menganalisa ICI (Inter-Carrier Interjérence). Simulasi dan analisa dilakukan dalam sistem OFDM dan EKF-OFDM pada tiga jenis kanal yaitu AWGN (Additive White Gaussian Noise), multymth 1 order, multipath 2 order dan multipath 3 order.Hasil analisa simulasi pada extended kalman filter-OFDM (EKF-OFDM) yang menggunakan proses koreksi CPE dalam kanal AWGN (Additive White Gaussian Noise), multipath 1 order, multipath 2 order dan multipath 3 order memiliki hasil yang baik, terutama jika keadaan phase noise tidak terlalu besar. Sehingga dengan menggunkan metoda extended kalman filter dapat mengurangi phase error dalam suatu transmisi komunikasi dari sistem OFDM.

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Orthogonal Frequency Division Multiplexing (OFDM) is multicarrier transmission technique, which divides the available spectrum into many carriers, each one being modulated by a low rate data stream. OFDM was represents the FDM (Frequency Division Multiplexing) special formula. However, OFDM uses the spectrum much more efficiently by spacing the channels much closer together. In OFDM communications system using smaller spectrum then divided into sub-carrier with smaller space at frequency distance, so that in OFDM bandwidth enable a more effective.OFDM was found to perform very well compared with FDM (Frequency Division Multiplexing) multicarrier teclmique. But OFDM has never been get out at the interference, such as phase error and ICI (Inter-can-ier Interference). This enables a more degradation at Qos (Quality Service Support) in OFDM communications system.EKF (Extended Kalman Filtering) method has done at linear and non-linier system, so that Extended Kalman Filtering method represents the complex implementation with modestly usage. Extended kalman filter method was efficient estimation algorithm to suppression ICI in OFDM communication system compared with self-cancellation and ML-estimation methods.This thesis has analysis the ICI (Inter-Carrier Interference) on extended kalman filter method of OFDM communication system. This analysis has done at theAWGN (Additive White Gaussian Noise) channel, multipath l order channel, multipath 2 order channel and multipath 3 order channel.The analysis results are showm of extended kalman filter method on OFDM which demonstrate the effectiveness of the AWGN (Additive White Gaussian Noise) channel, multipath l order channel, multipath 2 order channel and multipath 3 order channel, especially when low phase noise are required. So that, extended kalman filter method to suppress influence of phase error in OFDM communications system."

"Pentransmisian gambar pada jaringan telekomunikasi umum (public telecommunication network) merupakan hal yang sulit untuk dilakukan. Hal ini disebabkan karena selain dibutuhkan kapasitas yang sangat besar, laju bit pada gambar merupakan nilai yang berubah-ubah (VBR), sehingga sulit untuk menjaga efisiensi saluran komunikasi dengan tetap memelihara kualitas keluaran di sisi penerima. ATDM merupakan metode multipleksing yang setiap saat mendefinisikan kembali panjang frame-nya, sehingga cocok digunakan untuk media yang bersifat VBR.Tugas skripsi ini adalah untuk menganalisis unjuk kerja ATDM pada pentransmisian gambar. Hal pertama yang dilakukan adalah memodelkan suatu bentuk si Val gambar yang telah dikodekan, untuk menentukan parameter-parameter ATDM. Setelah itu baru dapat dibuat perhitungan antrian untuk mendapatkan unjuk kerja ATDM yang berupa nilai kemungkinan loss berbanding dengan ukuran bufer."

"Teknologi dalam bidang komunikasi nirkabel dalam kurun waktu terakhir menunjukkan perkembangan yang sangat pesat. Perkembangan tersebut mengarah kepada pemenuhan akan kebutuhan kapasitas yang tinggi, serta penggunaan bandwidth yang efisien dan kemampuan dalam menghadapi gangguan selama transmisi yang berujung pada minimnya eror selama pentransmisian data. Salah satu teknologi yang dapat memenuhi semua kebutuhan diatas adalah teknologi MIMO OFDM. Pada skripsi ini, disimulasikan dan dianalisis teknik MIMO OFDM dengan menggunakan teknik Spatial Multiplexing dalam pentransmisian datanya. Pemodelan kanal yang digunakan dalam simulasi ini berbasiskan operasi Singular Value Decomposition. Performansi sistem dalam simulasi ini dinyatakan dengan korespondensi Bit Error Rate (BER), Kapasitas Kanal dan Throughput terhadap Eb/No. Performansi sistem dilihat dengan tiga jenis modulasi, yaitu QPSK, 16 QAM dan 64 QAM. Unjuk kerja keseluruhan system divariasikan dengan jenis Error Control Coding (ECC) yang digunakan, dimana pada simulasi ini, terdapat tiga jenis ECC dengan coderate yang berbeda-beda. Selain itu, user dalam simulasi ini terdiri atas dua keadaan, yaitu user diam (v = 0 m/s) dan user bergerak (v = 10 m/s). Hasil simulasi menunjukkan bahwa unjuk kerja sistem makin baik dengan menggunakan Eb/No yang tinggi. Hal ini dilihat dari grafik BER, Kapasitas kanal, throughput dan juga sinyal konstelasi yang dihasilkan. Selain itu, dari hasil simulasi, diketahui unjuk kerja sistem paling baik didapatkan dengan menggunakan coderate 1/3.

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In recent years, wireless technology development shown rapid increasing. The development lead to fulfilled high capacity needs, using efficiently of bandwidth and ability to protect data from noise and minimizing error. Technology that suited with such conditions is MIMO OFDM.

In this undergraduate thesis, simulation and analysis of spatial multiplexing MIMO OFDM technique is proposed. Channel modeling that used in this simulation based on Singular Value Decomposition. The evaluation of system performance is proposed to Bit Error Rate (BER), Channel Capacity and Throughput parameter toward Eb/No value. Three type of modulation, that are QPSK, 16-QAM and 64-QAM are used in this simulation. For whole system performance, three type Error Control Coding is used in this simulation with different coderate value. Beside that, there are two user condition in this simulation, that are idle user (v = 0 m/s) and mobile user (v = 10 m/s).

The simulation results show that system performance with high Eb/No value is most better. This condition is shown for BER, channel capacity, throughput and signal space graph. In addition, we can see the performance with coderate 1/3 is also better than other coderate values."

"A novel encryption method for volume holographic storage using phase - coded multiplexing is presented...."

"One of service demand in wireless communication through air is service that base on multimedia with big capacity, high velocity, flexible , and small error. Nevertheless , known that the availability of bandwidth is limited, besides, the big bandwith can cause selective fading. Adaptive MIMO Switch (AMS) and adaptive Modulation (AM) technique are implemented to handle this problem. The principle of AMS technique is switching between Space Time Block Code (STBC) and Spatial Multiplexing (SM). While adaptive modulation is to change signal constellation (mapper) that used. AMS technique and adaptive modulation works due to feedback contains Channel State Information that represented with EB/No parameter. Coalition from both adaptive technique, hopefully can upgrade data rate with guarantee the qualities is still well-kept. In this research, AMS technique and adaptive modulation implemented in MIMO-OFDM mobile WiMAX (IEEE 802, 16e) system. The result of this research, MIMO OFDM system use AM+AMS give the performance improvement equal to kurang lebih 0,5 (data rate) and kurang lebih 1,5 dB (gain) to AM or AMS."

"Modeling, simulation, design and engineering of WDM systems and networks provides readers with the basic skills, concepts, and design techniques used to begin design and engineering of optical communication systems and networks at various layers. The latest semi-analytical system simulation techniques are applied to optical WDM systems and networks, and a review of the various current areas of optical communications is presented. Simulation is mixed with experimental verification and engineering to present the industry as well as state-of-the-art research. This contributed volume is divided into three parts. The first part of the book presents modeling approaches and simulation tools mainly for the physical layer including transmission effects, devices, subsystems, and systems), whereas the second part features more engineering/design issues for various types of optical systems including ULH, access, and in-building systems. The third part of the book covers networking issues related to the design of provisioning and survivability algorithms for impairment-aware and multi-domain networks."