Codes for Optical CDMA

Omrani, Reza; Kumar, P. Vijay

doi:10.1007/11863854_4

Cited by 16 publications

(13 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…So, the constructions of 2-D OOCs are important. Recently many researchers have been working on the design and construction of 2-D OOCs (see, e.g., [9,28,33,34,36,[39][40][41][42][44][45][46]). Most of these constructions are for λ = 1, 2, where either cross one type of sequence with another to improve the cardinality and correlation properties (see, e.g., [28,41,42]), or convert 1-D sequences to 2-D sequences to reduce the "timelike" property (see, e.g., [33,34,44]).…”

Section: (The Auto-correlation Property)mentioning

confidence: 99%

“…In such codes, the length of the codewords increases rapidly when the number of users or the weight of the code is increased, which means large bandwidth expansion is required if a large number of codewords are needed. As the length of the spreading code increases, ultrashort pulse have to be used, which are prone for nonlinear effects (see, e.g., [36,38,39]). To overcome this problem, several two-dimensional (2-D) codes have been proposed.…”

mentioning

confidence: 99%

See 1 more Smart Citation

On constructions for optimal two-dimensional optical orthogonal codes

Wang¹,

Shan

Yin³

2009

Des. Codes Cryptogr.

View full text Add to dashboard Cite

Two-dimensional optical orthogonal codes (2-D OOCs) are of current practical interest in fiber-optic code-division multiple-access networks as they enable optical communication at lower chip rate to overcome the drawbacks of nonlinear effects in large spreading sequences of one-dimensional codes. A 2-D OOC is said to be optimal if its cardinality is the largest possible. In this paper, we develop some constructions for optimal 2-D OOCs using combinatorial design theory. As an application, these constructions are used to construct an infinite family of new optimal 2-D OOCs with auto-correlation 1 and cross-correlation 1.

show abstract

Section: (The Auto-correlation Property)mentioning

confidence: 99%

mentioning

confidence: 99%

On constructions for optimal two-dimensional optical orthogonal codes

Wang¹,

Shan

Yin³

2009

Des. Codes Cryptogr.

View full text Add to dashboard Cite

show abstract

“…It is obvious that an (n × m, k, ρ) OPPW 2-D OOC is a special (n × m, k, ρ) AM-OPPW 2-D OOC with n = k. Let (n × m, k, ρ) denote the largest possible size of an (n × m, k, ρ) AM-OPPW 2-D OOC. The following upper bound for the value of (n ×m, k, ρ) can be found in [23,24,28]. An (n × m, k, ρ) AM-OPPW 2-D OOC is said to be optimal if its size is (n × m, k, ρ).…”

Section: An Applicationmentioning

confidence: 98%

“…Since the code length is necessarily large in practice, one drawback of 1-D OOCs is the requirement of an excessively high chip rate. For related details on 1-D OOCs, the interested reader may refer to [10,23,25].…”

Section: An Applicationmentioning

confidence: 99%

Semicyclic 4-GDDs and related two-dimensional optical orthogonal codes

Wang

2011

Des. Codes Cryptogr.

View full text Add to dashboard Cite

The existence problem for a semicyclic group divisible design (SCGDD) of type m n with block size 4 and index unity, denoted by 4-SCGDD, has been studied for any odd integer m to construct a kind of two-dimensional optical orthogonal codes (2-D OOCs) with the AM-OPPW (at most one-pulse per wavelength) restriction. In this paper, the existence of a 4-SCGDD of type m n is determined for any even integer m, with some possible exceptions. A complete asymptotic existence result for k-SCGDDs of type m n is also obtained for all larger k and odd integer m. All these SCGDDs are used to derive new 2-D OOCs with the AM-OPPW restriction, which are optimal in the sense of their sizes.

show abstract

“…The maximum number of optical orthogonal codes, Z, is given by the following Johnson bounds [1,2]. Johnson's bound A is,…”

Section: For These Codesmentioning

confidence: 99%

A general algorithm to design sets of all possible one dimensional unipolar orthogonal codes of same code length and weight

Chauhan¹,

Asthana²,

Singh

2010

2010 IEEE International Conference on Computational Intelligence and Computing Research

View full text Add to dashboard Cite

This paper describe a general scheme to design all the uni-polar codes characterized by parameter (n, w). The binary sequence of length 'n' ('n' bits) and weight 'w' (number of bit '1's in the sequence) with its n-1 circular shifted versions represent the same code. These codes can be further put in different subsets characterized by (n, w, c a λ λ , ), where a λ and c λ are auto-correlation and crosscorrelation constraint respectively. All the codes within a set are called orthogonal to each other. In reality, they are pseudo orthogonal as cross-correlation is non-zero. With parameter (n, w, c a λ λ , ), there can be many sets each containing a number of orthogonal codes. All the codes in one set are always orthogonal to each other but not necessarily orthogonal to the codes in other sets. The code design scheme presented in this paper, can design all possible sets of codes. Users can select the code set as per their requirements. These uni-polar one dimensional orthogonal codes have their application in incoherent optical code division multiple access systems. The uni-polar optical orthogonal code can be generated by putting a single optical pulse at every position of bit '1' and no pulses at the positions of bit '0's in the sequence.

show abstract

Codes for Optical CDMA

Cited by 16 publications

References 47 publications

On constructions for optimal two-dimensional optical orthogonal codes

On constructions for optimal two-dimensional optical orthogonal codes

Semicyclic 4-GDDs and related two-dimensional optical orthogonal codes

A general algorithm to design sets of all possible one dimensional unipolar orthogonal codes of same code length and weight

Contact Info

Product

Resources

About