Finding Non-liner Register on Binary M-Sequence Generating Binary Multiplication Sequence

In the current time there is an important problem that is for a received linear or nonlinear binary sequence {zn} how we can find the nonlinear feedback shift register and its linear equivalent which generate this sequence. The linear orthogonal sequences, special M-Sequences, play a big role in these methods for solving this problem. In the current research trying give illuminations about the methods which are very useful for solving this problem under short sequences, and study these methods for finding the nonlinear feedback shift register of a multiplication sequence and its linear equivalent feedback shift register of a received multiplication binary sequence{zn} where the multiplication on h degrees of a binary linear sequence {an}, or finding the equivalent linear feedback shift register of {zn}, where the sequence {zn}of the form M-sequence, and these methods are very effectively. We can extend these methods for the large sequences using programming and modern computers with large memory.

Generalization of Multiplication M-Sequences over Fp and Its Reciprocal Sequences

Mp-Sequences or M-Sequence over Fp not used so much in current time as binary M-Sequences and it is pending with the difficult to construct there coders and decoders of Mp-Sequences further these reasons there is expensive values to construct them but the progress in the technical methods will be lead to fast using these sequences in different life’s ways, and these sequences give more collection of information and distribution them on the input and output links of the communication channels, building new systems with more complexity, larger period, and security. In current article we will study the construction of the multiplication Mp-Sequence {zn}and its linear equivalent, this sequences are as multiple two sequences, the first sequence{Sn}is an arbitrary Mp-Sequence and the second sequence {ζn} reciprocal sequence of the first sequence {Sn}, length of the sequence {zn}, period, orthogonal and the relations between the coefficients and roots of the characteristic polynomial of f(x) and it’s reciprocal polynomial g(x) and compare these properties with corresponding properties in M-Sequences.

Performance Analysis of Bipolar Optical Code Division Multiple Access with Dual Electro-Optical Modulator Scheme for Free-Space Optical Communication

In this study, the performance of bipolar optical code division multiple access (OCDMA) with dual electro-optical modulator (EOM) scheme for multi-user scenario was tested and analyzed with OptiSystem version 10. The performance measurement was implemented for free-space optical (FSO) communication and includes the common noises in optical communication. Two different channels were used in the measurement, i.e., additive white Gaussian noise (AWGN) and fading channel. Two extreme weather conditions, strong rain and storm, were considered in the simulation. The performance between three spectral amplitude coding (SAC) codes, i.e., Modified M-Sequence code, Walsh-Hadamard code, and random diagonal (RD) code were measured and compared. The simulation results indicate that Modified M-Sequence code had the highest BER while RD code achieved the lowest BER in the short-range and Walsh-Hadamard code got the lowest BER for the medium-range of FSO, both for AWGN only and AWGN with fading channel. In strong turbulence condition, the performance of all codes become comparable after 500 m of FSO range. Modified M-Sequence suffered the lowest performance degradation while RD code endured the highest performance deterioration in all-weather condition. The results show that Modified M-Sequence can be applied for medium to long-range FSO.

Performance analysis of hybrid Fi-Wi network employing OCDMA based NG-PON

Fiber-Wireless (Fi-Wi) networks play a crucial role in broadband wireless communication. A hybrid Fi-Wi architecture integrating Optical Code Division Multiple Access (OCDMA) based Next-Generation Passive Optical Network (NGPON) with Long Term Evolution (LTE) is proposed that can provide a higher capacity to the mobile end users, thereby achieving scalability and mobility. Maximal length sequence (M-sequence) codes of code length 31 used can support six users. A simulation study is carried out for the proposed integrated architecture considering multiple users and multiple services, and the performance is analyzed in terms of the received Bit Error Rate (BER) and Error Vector Magnitude (EVM) values. A high capacity of 160 Gbps and a spectral efficiency of 2–4 bps/Hz are achieved for the multi-user and multi-service links with six users.

Study the Multiplication M-sequences and Its Reciprocal Sequences

M-Sequences play a big important role, as the other binary orthogonalsequences, for collection the information on the input links and distributionthese information on the output links of the communication channelsand for building new systems with more complexity, larger period, andsecurity, through multiplication these sequences. In our article we try tostudy the construction of the multiplication sequence {zn}and its linearequivalent, this multiplication sequence is as multiple two sequences, thefirst sequence{an}is an arbitrary M-sequence and the second sequence{bn}is not completely different but is the reciprocal sequence of the firstsequence {an} that is the reciprocal sequence has characteristic polynomialg(x) is reciprocal of f(x), which is the characteristic polynomial of the firstsequence {an}, also we will study the linear equivalent of the multiplicationsequence {zn}and we will see that the length of the linear equivalent of {zn}is equal to ((deg f(x))2 - deg(f(x)).

Design and Analysis of Three-dimensional M-sequence Bipolar OCDMA Spectral Amplitude Code

This paper has been focused to utilize the m-sequence code in spectral/time/spatial OCDMA domain in a bipolar mode (Three Dimensional modes). The scheme has elegantly incorporated the design of an encoder and a decoder such that the system efficiently generates the code in three-dimensional bipolar mode. The decoder design is such that it effectively suppresses the multiple user interference (MUI) of three-dimensional code. System analyses are carried for defining the BER performance variation with users acceptability and received power. The observed results demonstrate that the cardinality of m-sequence three-dimensioanl bipolar code is larger than the existing 3D Pascal code, 2D -MDW,3D -PDC, 2D-PDC, 1D-CWH and 1D-MS codes. The received power in proposed system is -5.8dBm is lesser than the 3D Pascal Code at 10 -18 similarly the users adoption in system more than 210% can be accomplished as compared to 3D Pascal code.