Playing with Blocks: A New Combination of Block Transmission and the CDMA Multiple Access Technique

Arevalo, Leonel; Medina, César A.; Sampaio‐Neto, Raimundo

doi:10.1109/vtcspring.2015.7146018

Cited by 4 publications

(14 citation statements)

References 10 publications

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“…To mitigate the MAI effects in DS-CDMA when the transmission is performed in frequency selective transmission channel, the CS-CDMA (Chip -Spread Code Division Multiple Access) has been proposed [5]. This technique combines the single carrier block transmission and an inversion between chips and information symbols in the traditional block CDMA.…”

Section: Introductionmentioning

confidence: 99%

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Chip-Spread CDMA Transmission: A Comparative Analysis

Pereira¹,

Arevalo²,

David³

et al. 2016

Anais De XXXIV Simpósio Brasileiro De Telecomunicações

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In this paper a detailed study of an efficient transmission technique, recently proposed, which combines the single carrier (SC) block transmission, and the code division multiple access (CDMA), referred to as chip spread CDMA (CS-CDMA), is performed. The main feature of CS-CDMA is that, unlike the tradicional direct sequence (DS-CDMA) transmission system, the code orthogonality between users is maintained even when the transmissions, are made through a multipath frequency selective time-invariant channels. Thus, CS-CDMA allows the decoupling of user signals at the reception side. However, existing comparisons between CS-CDMA and DS-CDMA only consider the up-link scenario and particular conditions, which include orthogonal user codes and time invariant channels. In this scenario the CS-CDMA technique has shown a significant superiority when compared with the traditional DS-CDMA transmission. A detailed analisys of the CS-CDMA techique in more general conditions is presented in this work. We consider different environments such as, time invariant and time varying transmission channels, both orthogonal and non-orthogonal users' codes and up-link and down-link scenarios. We adopt frequency domain equalization with MMSE (Minimum Mean Squared Error) detection. Numerical results with performance comparisons indicate that, despite the effects of non-ideal conditions, CS-CDMA maintains a clear superiority over the DS-CDMA transmission.

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Section: Introductionmentioning

confidence: 99%

“…This technique combines the single carrier block transmission and an inversion between chips and information symbols in the traditional block CDMA. Studies have demonstrated that CS-CDMA can eliminate the MAI even when the transmission is made through frequency selective multipath channels, assumed time-invariant [5].…”

Section: Introductionmentioning

confidence: 99%

Chip-Spread CDMA Transmission: A Comparative Analysis

Pereira¹,

Arevalo²,

David³

et al. 2016

Anais De XXXIV Simpósio Brasileiro De Telecomunicações

Self Cite

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“…The continuous transmission of CP-OFDM symbols and the channel action induce a superposition between the received OFDM symbols. Then, the i-th observation with dimension G × 1 can be expressed by [7] (2)(3)(4) where the matrix H is a G × G Toeplitz matrix that represents the channel behavior. Its first column is given by [h 0 h 1 ... h…”

Section: Ofdma Matrix Model Of Transmission and Receptionmentioning

confidence: 99%

“…These systems are affected by the inter-block interference (IBI), which can be avoided by the insertion of a guard interval [7]. The insertion of an appropriate guard interval also allows a significant simplification of the channel estimation and equalization process [2]. After insertion of the guard interval, the resulting symbol block can be transmitted using a multicarrier or single-carrier scheme.…”

Section: Introductionmentioning

confidence: 99%

“…This dissertation focuses on the study of two multiple access techniques proposed for using in block transmission systems. One combines single carrier block transmission using the CDMA multiplexing technique, known as Chip Spread Code Division Multiple Access (CS-CDMA) [2]. The other multiple access technique discussed is known as Orthogonal Frequency Division Multiple Access (OFDMA) [14].…”

Section: Introductionmentioning

confidence: 99%

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Orthogonal Multiple Access Schemes in Linear and Non-Linear Channels

HERNANDEZ¹

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Wireless communications are one of the pillars of the development of the new generations of mobile communications. Each generation has used some multiple access technique to take advantage of the channel's resources. This dissertation presents an analysis of two orthogonal multiplexing techniques. Both techniques implement block transmission, where one is combined with the Code Division Multiple Access (CDMA) approach, while the other uses the multicarrier transmission technique Orthogonal Frequency Division Multiplexing (OFDM). The performance and spectral occupation of both techniques and their advantages are analyzed. Analytical expressions for the Power Spectral Density of the signals were obtained, which allowed establishing comparisons between both methods. The study of these multiplexing techniques is carried out in different propagation channels to evaluate the behavior of both systems in general. The three types of channels evaluated in this work are linear and time-invariant, linear and time-variant and, finally, non-linear and time-invariant. Each type of channel was modeled in matrix form for both systems independently. The simulations consider the Zero Forcing and Minimum Mean Squared Error equalizers, assuming a known channel.

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Nonassisted adaptive algorithm for data fusion in distributed detection systems [Correspondence]

Sampaio‐Neto

Medina

2016

IEEE Trans. Aerosp. Electron. Syst.

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Playing with Blocks: A New Combination of Block Transmission and the CDMA Multiple Access Technique

Cited by 4 publications

References 10 publications

Chip-Spread CDMA Transmission: A Comparative Analysis

Chip-Spread CDMA Transmission: A Comparative Analysis

Orthogonal Multiple Access Schemes in Linear and Non-Linear Channels

Nonassisted adaptive algorithm for data fusion in distributed detection systems [Correspondence]

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