Cooperative non-orthogonal multiple access for wireless communication networks by exploiting the EXIT chart analysis

AbstractIn the next generation of mobile communication networks, unprecedented challenges are required to be met, such as much higher data rates and spectrum efficiency, lower latency, and massive connectivity. Non-orthogonal multiple access (NOMA) has recently been proposed as a promising technology to achieve much superior spectral efficiency compared to conventional orthogonal multiple access techniques employed in present communication systems. A salient feature of NOMA is its use of successive interference cancellation (SIC) to decode users’ information when multiple users are allowed to transmit in same time/frequency/code domain. In this paper, we aim to exploit an aspect of SIC, namely the availability of other users’ data to realize a cooperative NOMA system. EXtrinsic information transfer (EXIT) charts are utilized to examine the performance of proposed system in terms of user fairness while employing IRregular convolutional codes (IRCC)s. The EXIT chart using IRCC evaluates the convergence analysis for the proposed system. Further, to evaluate the system performances in cooperative NOMA system, we have derived the expressions for the achievable rates which are obtained independently and utilized them in evaluating the experimental data for the proposed NOMA model.

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Sparse code multiple access on the generalized frequency division multiplexing

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-020-01832-z ◽

2020 ◽

Vol 2020 (1) ◽

Author(s):

Guilherme P. Aquino ◽

Luciano L. Mendes

Keyword(s):

Communication Systems ◽

Orthogonal Frequency Division Multiplexing ◽

Multiple Access ◽

Physical Layer ◽

Spectrum Efficiency ◽

Sparse Code ◽

Frequency Division Multiplexing ◽

Frequency Division ◽

Time Frequency ◽

Performance Loss

Abstract Recent advances in the communication systems culminated in a new class of multiple access schemes, named non-orthogonal multiple access (NOMA), where the main goal is to increase the spectrum efficiency by overlapping data from different users in a single time-frequency resource used by the physical layer. NOMA receivers can resolve the interference among data symbols from different users, increasing the overall system spectrum efficiency without introducing symbol error rate (SER) performance loss, which makes this class of multiple access techniques interesting for future mobile communication systems. This paper analyzes one promising NOMA technique, called sparse code multiple access (SCMA), where C users can share U<C time-frequency resources from the physical layer. Initially, the SCMA and orthogonal frequency division multiplexing (OFDM) integration is considered, defining a benchmark for the overall SER performance for the multiple access technique. Furthermore, this paper proposes the SCMA and generalized frequency division multiplexing (GFDM) integration. Since GFDM is a highly flexible non-orthogonal waveform that can mimic several other waveforms as corner cases, it is an interesting candidate for future wireless communication systems. This paper proposes two approaches for combining SCMA and GFDM. The first one combines a soft equalizer, called block expectation propagation (BEP), and a multi-user detection (MUD) scheme based on the sum-product algorithm (SPA). This approach achieves the best SER performance, but with the significant increment of the complexity at the receiver. In the second approach, BEP is integrated with a simplified MUD, which is an original contribution of this paper, aiming for reducing the receiver’s complexity at the cost of SER performance loss. The solutions proposed in this paper show that SCMA-GFDM can be an interesting solution for future mobile networks.

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Performance Analysis of OFDMA vs. NOMA in Cognitive Radio Network

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.34751 ◽

2021 ◽

Vol 9 (VI) ◽

pp. 2483-2488

Author(s):

E. Alwin Richard

Keyword(s):

Communication Systems ◽

Orthogonal Frequency Division Multiplexing ◽

Multiple Access ◽

Spectrum Efficiency ◽

Frequency Division Multiplexing ◽

Frequency Division ◽

Time Frequency ◽

New Class ◽

Overlapping Data ◽

Multiple Access Schemes

Recent advancements in communication systems have resulted in a new class of multiple access schemes known as non-orthogonal multiple access (NOMA), the primary goal of which is to increase spectrum efficiency by overlapping data from different users in a single time-frequency resource used by the physical layer. NOMA receivers can resolve interference between data symbols from various users, hence increasing throughput. Initially, the combination of SCMA and orthogonal frequency division multiplexing (OFDM) is addressed, establishing a baseline for the overall SER performance of the multiple access strategy. Furthermore, this work suggests the merging of SCMA with generalised frequency division multiplexing (GFDM).GFDM is an intriguing possibility for future wireless communication systems since it is a very flexible non-orthogonal waveform that can imitate various different waveforms as corner cases. This research suggests two methods for integrating SCMA with GFDM.

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A Novel User Grouping Algorithm for Downlink NOMA

10.21203/rs.3.rs-413432/v1 ◽

2021 ◽

Author(s):

Navideh Ghafouri Jeshvaghani ◽

Naser Movahhedinia ◽

Mohammad Reza Khayyambashi

Keyword(s):

Interference Cancellation ◽

Multiple Access ◽

Spectrum Efficiency ◽

System Capacity ◽

Substantial Impact ◽

User Grouping ◽

Radio Access ◽

Power Domain ◽

Rate Maximization ◽

Sum Rate

Abstract Non-orthogonal multiple access (NOMA) is one of the promising radio access techniques for resource allocation improvement in the 5th generation of cellular networks. Compared to orthogonal multiple access techniques (OMA), NOMA offers extra benefits, including greater spectrum efficiency which is provided through multiplexing users in the transmission power domain while using the same spectrum resources non-orthogonally. Even though NOMA uses Successive Interference Cancellation (SIC) to repeal the interference among users, user grouping has shown to have a substantial impact on its performance. This prformance improvement can appear in different parameters such as system capacity, rate, or the power consumption. In this paper, we propose a novel user grouping scheme for sum-rate maximization which increases the sum-rate up to 25 percent in comparison with two authenticated recent works. In addition to being matrix-based and having a polynomial time complexity, the proposed method is also able to cope with users experiencing different channel gains and powers in different sub-bands.

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Doubly Orthogonal Wavelet Packets for Multi-Users Indoor Visible Light Communication Systems

Photonics ◽

10.3390/photonics6030085 ◽

2019 ◽

Vol 6 (3) ◽

pp. 85 ◽

Cited By ~ 1

Author(s):

Arslan Khalid ◽

Hafiz Muhammad Asif ◽

Konstantin I. Kostromitin ◽

Sattam Al-Otaibi ◽

Kazi Mohammed Saidul Huq ◽

...

Keyword(s):

Visible Light ◽

Communication Systems ◽

Multiple Access ◽

Visible Light Communication ◽

Wavelet Packets ◽

Easy Access ◽

Line Of Sight ◽

Detection Scheme ◽

Time Frequency ◽

Code Division Multiple

Visible Light Communication (VLC) is a data communication technology that modulates the intensity of the light to transmit the information mostly by means of Light Emitting Diodes (LEDs). The data rate is mainly throttled by the limited bandwidth of the LEDs. To combat, Multi-carrier Code Division Multiple Access (MC-CDMA) is a favorable technique for achieving higher data rates along with reduced Inter-Symbol Interference (ISI) and easy access to multi-users at the cost of slightly reduced compromised spectral efficiency and Multiple Access Interference (MAI). In this article, a multi-user VLC system is designed using a Discrete Wavelet Transform (DWT) that eradicates the use of cyclic prefix due to the good orthogonality and time-frequency localization properties of wavelets. Moreover, the design also comprises suitable signature codes, which are generated by employing double orthogonality depending upon Walsh codes and Wavelet Packets. The proposed multi-user system is simulated in MATLAB software and its overall performance is assessed using line-of-sight (LoS) and non-line-of-sight (NLoS) configurations. Furthermore, two sub-optimum multi-users detection schemes such as zero forcing (ZF) and minimum-mean-square-error (MMSE) are also used at the receiver. The simulated results illustrate that the doubly orthogonal signature waveform-based DWT-MC-CDMA with MMSE detection scheme outperforms the Walsh code-based multi-user system.

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Performance of M-Ary/ Spread Spectrum Multiple Access Communication Systems Using Co-Channel Interference Cancellation Techniques

10.1109/isssta.1992.665640 ◽

2005 ◽

Cited By ~ 5

Author(s):

S. Tachikawa

Keyword(s):

Spread Spectrum ◽

Interference Cancellation ◽

Communication Systems ◽

Multiple Access ◽

Channel Interference

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PERFORMANCE ANALYSIS OF MULTIPLE ACCESS CHAOTIC-SEQUENCE SPREAD-SPECTRUM COMMUNICATION SYSTEMS USING PARALLEL INTERFERENCE CANCELLATION RECEIVERS

International Journal of Bifurcation and Chaos ◽

10.1142/s0218127404011545 ◽

2004 ◽

Vol 14 (10) ◽

pp. 3633-3646 ◽

Cited By ~ 2

Author(s):

WAI M. TAM ◽

FRANCIS C. M. LAU ◽

CHI K. TSE

Keyword(s):

Spread Spectrum ◽

Interference Cancellation ◽

Communication Systems ◽

Multiple Access ◽

Minimum Mean Square Error ◽

Chaotic Sequence ◽

Spread Spectrum Communication ◽

Parallel Interference Cancellation ◽

Decorrelating Detector ◽

Error Detector

In this Letter, we apply combined linear detector/parallel interference cancellation (PIC) detectors to jointly decode symbols in a multiple access chaotic-sequence spread-spectrum communication system. In particular, three different types of linear detectors, namely single-user detector, decorrelating detector and minimum mean-square-error detector, are used to estimate the transmitted symbols at the first stage of the PIC detector. The technique for deriving the approximate bit error rate (BER) is described and computer simulations are performed to verify the analytical BERs.

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Intelligent reflected surfaces assisted code domain non-orthogonal multiple access scheme

Journal of Electrical Engineering ◽

10.2478/jee-2021-0048 ◽

2021 ◽

Vol 72 (5) ◽

pp. 343-347

Author(s):

Aasheesh Shukla

Keyword(s):

Communication Networks ◽

Information Transfer ◽

Multiple Access ◽

Wireless Communication Networks ◽

Radio Waves ◽

Reflection And Refraction ◽

Access Scheme ◽

Code Domain ◽

Efficient Code ◽

Phase Amplitude

Abstract The propagation medium plays a crucial role in any wireless communication networks, the channel between the transmitter and the receiver, deteriorate the quality of the received signal due to the uncontrollable interactions such as scattering, reflection, and refraction in the channel with the surrounding objects. To overcome this challenge, the recent advent of recongurable intelligent surfaces can be helpful, in which the network operators can control the radio waves, eg, the phase, amplitude, frequency, and even polarization, of the impinging signals without the need of complex decoding, encoding, and radio frequency processing operations. On the other hand, few research papers reported an efficient code domain non orthogonal multiple access (NOMA) such as Interleave division multiple access (IDMA) system for wireless information transfer. Persuaded by the capability of this arising RIS technology, the present article is aimed to provide the modified framework of IDMA (code-domain NOMA) communication system based on RIS technology. Simulation results demonstrate that the proposed system achieves better SNR performance than the conventional IDMA framework.

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Self-Interference Cancellation: A Comprehensive Review from Circuits and Fields Perspectives

Electronics ◽

10.3390/electronics11020172 ◽

2022 ◽

Vol 11 (2) ◽

pp. 172

Author(s):

Jiahao Zhang ◽

Fangmin He ◽

Wei Li ◽

Yi Li ◽

Qing Wang ◽

...

Keyword(s):

Interference Cancellation ◽

Communication Systems ◽

Base Station ◽

The Self ◽

Spectrum Efficiency ◽

Full Duplex ◽

Interference Signal ◽

Comprehensive Review ◽

To Come ◽

Transmitting Antenna

Increased demand for higher spectrum efficiency, especially in the space-limited chip, base station, and vehicle environments, has spawned the development of full-duplex communications, which enable the transmitting and receiving to occur simultaneously at the same frequency. The key challenge in this full-duplex communication paradigm is to reduce the self-interference as much as possible, ideally, down to the noise floor. This paper provides a comprehensive review of the self-interference cancellation (SIC) techniques for co-located communication systems from a circuits and fields perspective. The self-interference occurs when the transmitting antenna and the receiving antenna are co-located, which significantly degrade the system performance of the receiver, in terms of the receiver desensitization, signal masking, or even damage of hardwares. By introducing the SIC techniques, the self-interference can be suppressed and the weak desired signal from the remote transmitter can be recovered. This, therefore, enables the full-duplex communications to come into the picture. The SIC techniques are classified into two main categories: the traditional circuit-domain SICs and the novel field-domain SICs, according to the method of how to rebuild and subtract the self-interference signal. In this review paper, the field-domain SIC method is systematically summarized for the first time, including the theoretical analysis and the application remarks. Some typical SIC approaches are presented and the future works are outlooked.

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