Performance evaluation of MC-CDMA over hybrid satellite/underwater acoustic channel

Trivedi, Vinay Kumar; Agarwal, Akash; Kumar, Preetam

doi:10.1109/icics.2015.7459971

Cited by 8 publications

(3 citation statements)

References 15 publications

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“…The direct implementation of CI matrix needs approximately (2 M 2 − 3 M − 1) operations for large M , which can be reduced using efficient FFT/inverse fast fourier transform (IFFT) implementation to 1.5 M .log 2 M operations. However, unlike others, CI codes can be generated for any value of M and can also support overloading of users to increase capacity at the expense of minor BER degradation . For a fair comparison, the transmit power after inverse transform utilizing each precoding technique here must be normalized to the same value.…”

Section: System and Signal Modelmentioning

confidence: 99%

Trigonometric transforms and precoding strategies for OFDM‐based uplink hybrid multi‐carrier nonorthogonal multiple access

Trivedi

Ramadan

Kumar

et al. 2019

Trans Emerging Tel Tech

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An uplink hybrid nonorthogonal multiple access (h-NOMA) scheme utilizing power domain multiplexing is adopted in this paper for orthogonal frequencydivision multiplexing (OFDM)-based systems. The OFDM-based NOMA systems can achieve high spectral efficiency with resilience to wireless multipath fading. The h-NOMA maintains a low interference level per resource block or low complexity of multiuser detection (MUD) implementation at the receiver and also achieves consistent fairness performance by restricting the maximum number of users per resource block. An improved user clustering algorithm for OFDM-based h-NOMA system under the assumption of user's distinct data rate requirement is presented here. The proposed algorithm takes into consideration both the channel gain of all activated users and the different data rate requirements of weak channel gain users. High peak-to-average power ratio (PAPR) and performance degradation due to strict frequency synchronization requirements are the main drawbacks of such an OFDM-based uplink h-NOMA system. High PAPR of multicarrier NOMA is addressed here with precoding techniques. An enhanced minimum mean square error (MMSE) receiver performing joint equalization and carrier frequency offset (CFO) compensation using low-complexity banded-matrix implementation is proposed to cancel interference in the frequency domain. The MUD is implemented with low-complexity successive interference cancellation (SIC) using bandedmatrix approximation of the interference matrix in the presence of CFO. Moreover, the possibility of utilizing efficient trigonometric transforms to implement OFDM-based NOMA is studied with CFO and estimation errors. For OFDM-based h-NOMA system, an efficient combination of different trigonometric transform configurations to constitute the multicarrier basis for OFDM with a suitable precoding strategy for PAPR reduction is studied.Trans Emerging Tel Tech. 2019;30:e3694.wileyonlinelibrary.com/journal/ett

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Section: System and Signal Modelmentioning

confidence: 99%

Trigonometric transforms and precoding strategies for OFDM‐based uplink hybrid multi‐carrier nonorthogonal multiple access

Trivedi

Ramadan

Kumar

et al. 2019

Trans Emerging Tel Tech

Self Cite

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“…The preliminary results of simulation and pool testing indicate that MC-CDMA is a feasible method for designing the physical layer of UASNs. VK Trivedi et al 20 present the performance analysis of full-load and overload MC-CDMA transmission scheme over underwater acoustic channel. The authors use Walsh–Hadamard and carrier interferometry (CI) spread codes for the full-load case and use pseudo orthogonal (PO)-CI code for the overload case.…”

Section: Related Workmentioning

confidence: 99%

Convex optimization–based multi-user detection in underwater acoustic sensor networks

Wang

Zhang

Chen

et al. 2018

International Journal of Distributed Sensor Networks

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Multi-carrier code-division multiple access is an important technical means for high-performance underwater acoustic sensor networks. Nevertheless, severe multiple access interference is a huge challenge. As the core technology, multiuser detection is used to eliminate multiple access interference. The traditional optimal detection algorithms (e.g. maximum likelihood) have very high computational complexity, and the performances of suboptimal detection methods (i.e. zero forcing, minimum mean square error, etc.) are poor. Therefore, taking into account the characteristics of underwater acoustic sensor networks, it is of great significance to design multiuser detection algorithms for achieving a tradeoff between the detection performance and the computational complexity in multi-carrier code-division multiple access systems. In this article, we design a transmitter model of underwater multi-carrier code-division multiple access system and then implement a multiuser detection algorithm based on convex optimization, which is named convex optimization-based algorithm. Next, we conduct the detection performance and computational complexity comparisons of maximum likelihood, zero forcing, minimum mean square error, and convex optimization-based algorithm. The results show that the performance of convex optimization-based algorithm is close to that of maximum likelihood, and the complexity is close to that of zero forcing. Therefore, a tradeoff between the computational complexity and the detection performance is realized in convex optimization-based algorithm. It means that convex optimization-based algorithm is suitable for the multiuser detection in multi-carrier code-division multiple access systems of underwater acoustic sensor networks.

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“…In [10], authors have proposed an asymmetric satellite-UOWC system based on a decode-and-forward (DF) relay for oceanic monitoring purposes, where the UWOC was based on cascaded independent non-identically distributed Gamma-Gamma channel coefficients and the satellite link was a Shadowed-Rician distribution. A hybrid satellite-underwater acoustic was presented in [11]. The authors in [12], have evaluated the average bit error rate'sclosed-form expression for a satellite-UOWC system that used EGG distribution for the UWOC link.…”

Section: Introductionmentioning

confidence: 99%

Reliability of Spectrum-Efficient Mixed Satellite-Underwater Systems

Gamal

Elsayed

Samir

et al. 2022

IEEE Open J. Commun. Soc.

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The combination of radio-frequency (RF) communication and underwater optical wireless communication (UOWC) plays a vital role in the underwater Internet of things (UIoT). This correspondence proposes a dual-hop hybrid satellite underwater system that exploits non-orthogonal multiple access (NOMA) as a spectrum-efficient access technique. The RF link from the satellite to the relay on an oil platform is presumptively subject to a Shadowed-Rician (SR) fading, while the UOWC channels from the relay to the underwater destinations are suggested to follow Exponential-Generalized Gamma (EGG) distributions. The reliability of the system is characterized in terms of both underwater destinations and system outage probabilities (OPs). We derive new closed-form expressions for the OPs under imperfect successive interference cancellation (SIC) conditions. Furthermore, the asymptotic OP and the diversity order (DO) are obtained to learn more about the system's performance. The results are verified through an extensive representative Monte-Carlo simulation. Also, we investigate the performance against the turbulence of the salty water, air bubbles level (BL), temperature gradients (TG), shadowing parameters, and satellite pointing errors due to satellite motion, even if the beam is pointed at the center of the directive antenna relay, the beam will randomly oscillate. Finally, we contrast our approach with the conventional orthogonal multiple access (OMA) scheme to demonstrate its superiority.INDEX TERMS Satellite, underwater optical wireless communication, non-orthogonal multiple access, outage probability.

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Performance evaluation of MC-CDMA over hybrid satellite/underwater acoustic channel

Cited by 8 publications

References 15 publications

Trigonometric transforms and precoding strategies for OFDM‐based uplink hybrid multi‐carrier nonorthogonal multiple access

Trigonometric transforms and precoding strategies for OFDM‐based uplink hybrid multi‐carrier nonorthogonal multiple access

Convex optimization–based multi-user detection in underwater acoustic sensor networks

Reliability of Spectrum-Efficient Mixed Satellite-Underwater Systems

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