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In this paper, the detection algorithms of two generalized spatial modulation (GSM) schemes in a multiple-input multiple-output (MIMO) visible light communication (VLC) system are developed and analyzed. The considered optical GSM schemes are GSM with Transmit Diversity (GSM-TD) and GSM with Multi-Stream (GSM-MS). By allowing each activated LED to transmit independent temporal symbols simultaneously, GSM-MS benefits from higher bits per channel use (bpcu) than the GSM-TD scheme. Existing maximum likelihood (ML) detection algorithm is computationally prohibitive; hence, we develop a two-stage (identification followed by detection) receiver that decodes the spatial and temporal symbols in a sequential manner. In the first stage, we propose two algorithms, namely subspace tracking and spatial matched filtering (SMF), to identify the indices of activated LEDs, while in the second stage, effective matched filter (EMF) and decorrelating detector are employed to extract temporal symbols for GSM-TD and GSM-MS scheme, respectively. The performance assessment, including the computation load, correct identification probability and the average symbol error rate (SER), is comprehensively evaluated by computation simulation. It is shown that the complexity of the proposed two detection algorithms is extensively reduced compared with the ML algorithm. It is also demonstrated that ML detector offers the best SER performance; nevertheless, SER of the proposed algorithms approaches ML detector in high signal-to-noise ratio (SNR) or large receiver array size scenarios. [ABSTRACT FROM AUTHOR]

In this paper, we propose a hybrid decode-and-forward and soft information relaying (HDFSIR) strategy to mitigate error propagation in coded cooperative communications. In the HDFSIR approach, the relay operates in decode-and-forward (DF) mode when it successfully decodes the received message; otherwise, it switches to soft information relaying (SIR) mode. The benefits of the DF and SIR forwarding strategies are combined to achieve better performance than deploying the DF or SIR strategy alone. Closed-form expressions for the outage probability and symbol error rate (SER) are derived for coded cooperative communication with HDFSIR and energy-harvesting relays. Additionally, we introduce a novel normalized log-likelihood-ratio based soft estimation symbol (NL-SES) mapping technique, which enhances soft symbol accuracy for higher-order modulation, and propose a model characterizing the relationship between the estimated complex soft symbol and the actual high-order modulated symbol. Furthermore, the hybrid DF-SIR strategy is extended to a distributed Alamouti space-time-coded cooperative network. To evaluate the~performance of the proposed HDFSIR strategy, we implement extensive Monte Carlo simulations under varying channel conditions. Results demonstrate significant improvements with the hybrid technique outperforming individual DF and SIR strategies in both conventional and distributed Alamouti space-time coded cooperative networks. Moreover, at a SER of 10 − 3 , the proposed NL-SES mapping demonstrated a 3.5 dB performance gain over the conventional averaging one, highlighting its superior accuracy in estimating soft symbols for quadrature phase-shift keying modulation. [ABSTRACT FROM AUTHOR]

In this paper, we propose a multiple-input multiple-output receiver with deep learning. To obtain the high performance of the maximum likelihood receiver while maintaining the low computational complexity of the linear receiver, we apply a signal-to-noise ratio-based receiver-type decision method. Specifically, the criterion and threshold, which are based on the ratio between the symbol error probabilities of both receivers, to decide the receiver type are presented. For this, we analyze the signal-to-noise ratio gain of the zero-forcing receiver and exploit it as an input feature of the DNN. The simulation results demonstrate that the proposed receiver achieves a symbol error rate performance nearly identical to that of the maximum likelihood receiver with low computational complexity. [ABSTRACT FROM AUTHOR]

In this paper, we present a comprehensive investigation on security-reliability trade-off (SRT) in cooperative wireless networks in which full-duplex intermediate nodes act as jammer and/or relay. Various cooperative schemes named as opportunistic relay selection (ORS), opportunistic jammer selection (OJS), hybrid relay-jammer selection (HRJS), and joint relay-jammer selection (JRJS) are considered. In these schemes, relay and jammer sets are distinguished by comparing the instantaneous and average fading properties of the main and wiretap links, respectively. So that, one or two helpers from these sets are opportunistically employed for cooperation regarding the applied scheme. We analyze the outage and intercept probabilities and derive closed-form expressions for the SRT of the considered schemes. The results show that the cooperative schemes deliver different behaviors by varying parameters such as number of helpers, link quality and data rate. In details, ORS outperforms the other schemes for high main to eavesdropper ratio (MER), whereas JRJS delivers better performance for lower MERs. By improving the relay-to-destination link compared to source-to-destination, both HRJS and JRJS outperform the ORS while HRJS delivers better SRT than JRJS. Moreover, HRJS outperforms JRJS at higher data rates. The results also indicate that SRT of all schemes is improved by increasing the number of helpers. [ABSTRACT FROM AUTHOR]

For communication in space, information transmission lines are critical for reaching the whole world. A long delay and a poor data transfer rates have been observed in radio frequency (RF) communication and therefore inter-satellite communication has become more common in recent years and optical wireless communication has advanced dramatically. Owing to its multiple advantages, including large channel bandwidth, high-speed connectivity and economical operations, IsOWC technology is becoming popular among researchers. Uniphase modulations such as NRZ modulation does not have efficient spectrum for high speed inter-satellite communication. PDM-256-QAM at 160 Gbps over IsOWC channel is demonstrated in this work using matched filter and DSP. Proposed system is investigated for PDM-256-QAM at 850 and 1550 nm wavelength and results analyzed in terms of Q factor, log symbol error rate (SER) and error vector magnitude (EVM). [ABSTRACT FROM AUTHOR]

The paper analyzes the error performance of a basic satellite‐terrestrial communication system, which uses a satellite as a source and receiver at the earth station as a destination. The system model accounts for an independent channel of fading and applies the theory of non‐orthogonal multiple access (NOMA) to provide fair resource sharing and better connectivity among multiple users. The paper investigates the transmission characteristics and derives the expressions for the total symbol error rate (SER) of the proposed system model. Furthermore, it examines the transmission efficiency with the help of the elevation angle between the source and the destination. The paper also explores the impact of different fading environments on SER. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: In wireless communication, impulsive noise often degrades channel quality, which poses challenges for equalizers. Although robust equalization methods offer some effectiveness, the occurrence of impulsive noise after training significantly impacts the symbol error rate (SER). To mitigate this issue, we propose a method that involves denoising the received signal using robust wavelet decomposition before equalization. This approach combines the discrete wavelet transform with median and morphological filters to reduce impulsive noise. A pre‐impulsive noise detection mechanism triggers denoising only when impulsive noise is detected. We evaluate the SER performance of the proposed technique using simulations of a 16‐QAM orthogonal frequency division multiplexing (OFDM) system with kernel interpolation‐based frequency domain equalization (FDE) in a Rayleigh fading channel with impulsive noise. Results show that our approach achieves SER levels comparable to conventional methods in Gaussian noise scenarios, demonstrating its effectiveness in challenging wireless communication environments. The simulation results demonstrate that the proposed technique in non‐Gaussian noise gives the SER on par with the FDE in a Gaussian noise environment. [ABSTRACT FROM AUTHOR]

Summary: This paper considers multiuser downlink transmission and detection in a multiple input‐multiple output (MIMO) visible light communication (VLC) system. We combine two promising techniques: space‐shift keying (SSK) and optical orthogonal codes (OOCs). Multiuser downlink transmission is realized by allowing each activated LED to transmit user‐specific OOC simultaneously. An OOC despreader is implemented at the front end of each user terminal (UT) to extract the desired signal and mitigate multiuser interference (MUI). The second part of UT receiver aims to extract the index of the corresponding active LED based on maximum likelihood (ML) or zero‐forcing (ZF) algorithm. The figure of merit we used to access the performance of the proposed downlink multiuser SSK system is the average symbol error rate (SER). Comprehensive Monte Carlo simulations have been undertaken for different system setup to evaluate SER at UT receiver. It is demonstrated that for a specified SER, the required SNR for ML‐based detection algorithm is 3 dB less than the ZF detector in the MUI‐free scenario. On the other hand, the ZF detector outperforms ML detector in the case with residual MUI and limited channel state information (CSI). Both algorithms are computationally attractive, hence can be put into practice in multiuser VLC MIMO system. [ABSTRACT FROM AUTHOR]

This paper studies the interference impact on the performance of reconfigurable intelligent surface (RIS)-equipped decode-and-forward (DF) relay networks, where RIS is used as internal part of both the source and relay nodes. For that purpose, approximate closed-form expression is derived for the system outage probability assuming Rayleigh fading channels and opportunistic relaying scheme. Furthermore, to get more insights at the system performance, an approximate but accurate expression is achieved for the outage probability at the high signal-to-noise ratio (SNR) regime, where the system diversity order and coding gain are obtained and analyzed. The findings show that the system can achieve a diversity order of G d = min (N 1 , N 2) K , where N 1 and N 2 are the numbers of reflecting elements at the source and relays, respectively, and K is the number of relays. Additionally, results illustrate that for the same diversity order, utilizing one relay with multiple reflecting elements gives better performance than utilizing multiple relays each with a single reflecting element. Moreover, findings show that the number of relays not only affects the system diversity order, but also the coding gain of the first hop when it is dominating the system performance. Furthermore, results illustrate that when N 1 = N 2 , the system performance is dominated by the largest interference at either the relay node or the destination. With unequal interference powers, changing number of interferers at the node where interference is larger affects the performance, whereas changing number of interferers at the other node has no effect on the system behavior. On the other hand, when both nodes have the same interference power, changing number of interferers at either node by the same amount results in the same effect on the system performance. [ABSTRACT FROM AUTHOR]

Generalized frequency division multiplexing (GFDM) is a flexible block‐structured multi‐carrier scheme recently proposed for next‐generation wireless communication systems. There are various approaches suggested for its analysis and implementation via simulations but testing in real‐time environments is not heavily investigated. This paper carries out the real‐time implementation of the GFDM system utilizing software‐defined radio (SDR) by emphasizing mainly channel estimation and synchronization. Symbol timing, frequency offset, and channel estimate algorithms are applied using a windowed preamble with two identical halves to satisfy low egress noise requirements. Time and frequency estimation is evaluated in terms of residual offsets along with symbol error rate over frequency selective channels. This algorithm is extended to a preamble composed of multiple identical parts. This facilitates a large frequency estimation range at the cost of complexity. For practical validation of the above concepts, the National Instruments (NI) universal software radio peripheral (USRP) 2953R is employed as hardware and it is interfaced with LabVIEW. [ABSTRACT FROM AUTHOR]

Nowadays, especially with the developments in the automotive industry, it has become a highly popular topic for radar and communication systems to operate on the same platform and perform joint tasks to increase situational awareness. Sharing the hardware of the radar and communication systems and using a joint waveform for both functions eliminate interference problems between the systems, increasing the effectiveness of the joint task. In studies where radar signals are utilised for communication functions, continuous wave frequency modulation or intra‐pulse frequency modulation is generally employed to transmit communication signals. There are a few studies in the literature on joint radar and communication waveforms using phase modulation. In these studies, phase modulation is not employed directly for both functions. As a contribution to the literature, this study evaluates the usage of joint radar and communications waveforms, such as Barker sequences and Zadoff–Chu sequences as opposed to linear frequency modulation. We compare these waveforms terms of range‐speed detection and symbol error rate. [ABSTRACT FROM AUTHOR]

The utilization of fiber systems for transmitting millimeter-wave (MMW) signals has gained significant traction in recent years, particularly for advanced wireless communication applications such as 5G and beyond. This paper explores the integration of wireless and optical networks to enhance performance by reducing the error vector magnitude (EVM) and symbol error rate (SER). The proposed system employs a 2×2 multiple-input multiple-output (MIMO) configuration, which improves coverage and increases capacity through spatial multiplexing. MIMO systems are critical to modern wireless networks, providing superior spectrum and energy efficiency compared to earlier single-input-single-output systems. Following MIMO processing, a millimeter-wave signal is modulated onto the subcarrier using a Mach-Zehnder modulator (MZM). The signal is sent across a (50 and 70)-kilometer optical cable, which boosts data rate and frequency but introduces errors. The proposed method uses a convolutional neural network (CNN) correction to lower these errors and equalize to balance the SER and EVM. VPIphotonics and Python programming are utilized to put the system into practice. The proposed system has a bandwidth of 17 GHz and a data rate of 56.656 Gb/s; the center frequency is 160 GHz with EVM ≈ 3% at the 50 km distance and ≈ 4% at the 70 km fiber channel length. [ABSTRACT FROM AUTHOR]

This study proposes a covert communication system, in which a non-zero-mean normally distributed random process is used as a carrier, and its mean is modulated by a Walsh code carrying M covert bits. The number of combinations is so huge that it is difficult for malicious parties to decode the covert information, even if they are aware of the existence of the transmitting signal. The received signal is multiplied at the receiving end with eachWalsh code, and the mean value is computed. The Walsh code corresponding to the largest mean value is the transmitter's modulation code, thus recovering the transmitted covert bits. The system's theoretical symbol error rate and bit error rate are derived under additive white Gaussian noise and quasi-static fading channels, respectively. Simulation results are very consistent with the theoretical derivation. Compared with other existing schemes, the proposed scheme has good security, flexibility, and BER performance, and is very suitable for IoT devices with limited resources and low transmission rate but high concealability requirements. [ABSTRACT FROM AUTHOR]

We aim to improve both the energy harvesting efficiency and communication reliability of overlay networks powered by harvested energy. To this end, multiple antennas are considered to collect energy efficiently and perform reliable decoding by selecting the transmitting antenna and applying maximum‐ratio combining. To further improve communication reliability, nonorthogonal multiple access (NOMA)‐relied decoding is applied to the secondary receiver. For performance evaluation, exact formulas for the secondary/primary outage probability are derived in a closed form. The evaluation results show that the proposed method substantially outperforms a baseline without the NOMA‐relied decoding in all the system settings. The performance of the proposed method is determined by multiple specifications and optimized by allocating the times for energy harvesting and information processing. [ABSTRACT FROM AUTHOR]

In the 6G mobile networks, ensuring low latency and low energy consumption is paramount. This study explores a novel approach for addressing these issues in a backscatter communication (BC) - based multiple user unmanned aerial vehicle (UAV) - enabled mobile edge computing (MEC) Internet of Things (IoT) network. Our proposed framework incorporates a partial offloading strategy, a time division multiple access (TDMA) scheme, and a radio frequency energy harvesting mechanism. We use the channel gains statistical characteristics to derive approximate closed-form expressions for the successful computation and energy outage probabilities. Using these benchmarks, we investigate the impact of critical parameters such as transmit power, number of sensor nodes, task division ratio, the altitude of the UAV, and threshold tolerance. We validate our analysis through computer simulations and provide results to support our findings. The study reveals that selecting an optimal UAV altitude can significantly improve latency and energy consumption performance. [ABSTRACT FROM AUTHOR]

In this paper, we present the evaluation of network parameters for the unmanned aerial vehicle (UAV)-enabled triple-hop mixed RF/FSO-based wireless communication system, where one relay is a fixed relay and the second relay is a UAV which acts as decode-and-forward relay for communication from the base station (B) to the multiple mobile users (M i) ,   i ∈ { 1 , 2 ⋯ N } . The first hop from B to fixed relay (R1) is the radio frequency (RF) link modeled using α − κ − μ fading distribution, the second hop from the relay R1 to the UAV relay (R2) is a free space optics (FSO) link modeled using Gamma-Gamma fading, and the third hop from R2 to the M i is, again, an RF link modeled using the Rayleigh fading model. The direct communication between the B and the M i is not feasible due to the very large distance. We derive the closed form analytical expression for the outage probability of the proposed system and find the effect of the base system parameters on the performance of the system. We also analyze the outage probability of the system at high SNR values to get further insights of the system performance. In addition, altitude optimization of UAV is carried out to know the optimal elevation angle in correspondence with UAV's optimal altitude in order to maximize performance of the system. [ABSTRACT FROM AUTHOR]

In this work, we consider Terahertz (THz) communications with low-resolution uniform quantization and spatial oversampling at the receiver side, corresponding to a single-input multiple-output (SIMO) transmission. We fairly compare different analog-to-digital converter (ADC) parametrizations by keeping the ADC power consumption constant. Here, 1-, 2-, and 3-bit quantization is investigated with different oversampling factors. We analytically compute the statistics of the detection variable, and we propose the optimal and several suboptimal detection schemes for arbitrary quantization resolutions. Then, we evaluate the symbol error rate (SER) of the different detectors for 16- and 64-ary quadrature amplitude modulation (QAM). The results indicate that there is a noticeable performance degradation of the suboptimal detectors compared to the optimal detector when the constellation size is larger than the number of quantization levels. Furthermore, at low signal-to-noise ratios (SNRs), 1-bit quantization outperforms 2- and 3-bit quantization, respectively, even when employing higher-order constellations. We confirm our analytical results by Monte Carlo simulations. Both a pure line-of-sight (LoS) and a more realistically modeled indoor THz channel are considered. Then, we optimize the input signal constellation with respect to SER for 1- and 2-bit quantization. The results give insights for optimizing higher-order constellations for arbitrary quantization resolutions and show that the minimum SER can be lowered significantly by appropriately placing the constellation points.

ABSTRACT In this paper, a passive reflective intelligent surface (RIS) assisted bidirectional full‐duplex (FD) wireless system in a realistic Nakagami‐m$$ m $$ fading with N$$ N $$ reflective elements and two source nodes is proposed. The source nodes are equipped with dual antennas for FD mode transmission and reception. The primary cause of degradation in the performance of the FD system is self‐interference, which can be reduced by increasing the number of reflective elements on the meta‐surface. Analytical expressions have been derived for the proposed RIS‐aided bidirectional FD wireless systems in terms of outage probability and bit error rate (BER). Numerical results show that doubling the number of reflecting elements considerably improves the outage performance of the proposed system in terms of signal‐to‐noise ratio (SNR) compared with RIS‐assisted half‐duplex (HD) mode. Additionally, different modulation schemes have been employed to evaluate the BER performance of the proposed system. The accuracy of analytical expressions is validated by matching Monte Carlo with analytical simulations. [ABSTRACT FROM AUTHOR]

Cooperative MIMO communication systems play an important role in the development of future sixth-generation (6G) wireless systems incorporating new technologies such as massive MIMO relay systems, dual-polarized antenna arrays, millimeter-wave communications, and, more recently, communications assisted using intelligent reflecting surfaces (IRSs), and unmanned aerial vehicles (UAVs). In a companion paper, we provided an overview of cooperative communication systems from a tensor modeling perspective. The objective of the present paper is to provide a comprehensive tutorial on semi-blind receivers for MIMO one-way two-hop relay systems, allowing the joint estimation of transmitted symbols and individual communication channels with only a few pilot symbols. After a reminder of some tensor prerequisites, we present an overview of tensor models, with a detailed, unified, and original description of two classes of tensor decomposition frequently used in the design of relay systems, namely nested CPD/PARAFAC and nested Tucker decomposition (TD). Some new variants of nested models are introduced. Uniqueness and identifiability conditions, depending on the algorithm used to estimate the parameters of these models, are established. Two families of algorithms are presented: iterative algorithms based on alternating least squares (ALS) and closed-form solutions using Khatri–Rao and Kronecker factorization methods, which consist of SVD-based rank-one matrix or tensor approximations. In a second part of the paper, the overview of cooperative communication systems is completed before presenting several two-hop relay systems using different codings and configurations in terms of relaying protocol (AF/DF) and channel modeling. The aim of this presentation is firstly to show how these choices lead to different nested tensor models for the signals received at destination. Then, by capitalizing on these models and their correspondence with the generic models studied in the first part, we derive semi-blind receivers to jointly estimate the transmitted symbols and the individual communication channels for each relay system considered. In a third part, extensive Monte Carlo simulation results are presented to compare the performance of relay systems and associated semi-blind receivers in terms of the symbol error rate (SER) and channel estimate normalized mean-square error (NMSE). Their computation time is also compared. Finally, some perspectives are drawn for future research work. [ABSTRACT FROM AUTHOR]

The Orthogonal Frequency Division Multiplexing (OFDM) is a widely used transmission technique that allows feasible modulation and demodulation in wireless communication. In the OFDM system, the high Peak-to-Average Power Ratio (PAPR) is a complex task when finding the optimum phase factor. Therefore, this research proposed a Partial Transmit Sequence-Nonlinear variation convergence factor with Spotted Hyena Optimization (PTS-NSHO) for reducing PAPR in OFDM. The PTS-NSHO finds the optimum phase factor by recognizing other possible local areas in global space through precise and quick convergence. For signal encoding and decoding in OFDM, the Low-Density Parity-Check (LDPC) and Space Time Block Code (STBC) are applied. The Quadrate Amplitude Modulation (QAM-16) is used for signal modulation and demodulation. The PTS is used for PAPR reduction in which the phase factor is optimized through the proposed PTS-NSHO algorithm. The Additive White Gaussian Noise (AWGN) channel is used to transmit signals from transmitter to receiver. The Symbol Error Rate (SER), Bit Error Rate (BER) and Complementary Cumulative Distribution Function (CCDF) are used to estimate the PTS-NSHO performance. The PTS-NSHO achieved less PAPR of 3.8dB for CCDF=10-3 which is better than existing optimization such as Partial Transmit Sequence-Chaotic Sand Cat Swarm Optimization (PTS-CSCSO). [ABSTRACT FROM AUTHOR]

This work proposes a new hybrid bidirectional standard single mode fiber (SSMF)/free space optical (FSO) dual polarization quadrature amplitude modulation (DP‐QAM) employing optical orthogonal frequency division multiplexing (OFDM). An optical multicarrier generator (OMG) source is utilized. The suggested model is simulated using VPI photonics software. Thirty‐two optical OFDM channels are used; each carrier's 30 Gbps information data with DP‐QAM are employed to improve the performance of the fifth‐generation passive optical network (5G‐PON) for downstream and upstream transmission. In addition, 16‐QAM signals are used in DP. The impact of continuous wavelength (CW) lasers and high data rates in the proposed 5G‐PON has been investigated for DP‐QAM‐OFDM. The results reveal 0.96 Tb/s and 0.1 Tb/s for the downstream and upstream directions, respectively, under different turbulence effects. Furthermore, the simulation results show that the proposed model can achieve an SSMF length and FSO propagation ranges of 20 km and 2 km, respectively, with the symbol error rate (SER) (<10−9) and error vector magnitude (EVM) (<0.186). [ABSTRACT FROM AUTHOR]

Summary: The present research work aims to investigate the reliability of the mixed free space optical (FSO)/radio frequency (RF) decode‐and‐forward (DF) relaying system where the satellite intends to communicate with the ground station through the unmanned aerial vehicles (UAV) as the relay node. Moreover, it has been considered that a second UAV interferes with the intended UAV. The operation of the UAVs has been represented considering the small scale fading, path loss, 3‐D location, and probability of maintaining line‐of‐sight (LoS) and non line of sight (NLoS) links, while FSO link undergoes Malaga distributed turbulence. Using the aforementioned model, the closed form expressions for the outage probability and bit error rate (BER) have been derived. The exact expressions have been extended to obtain the high signal‐to‐noise ratio (SNR) results for the outage probability and BER. The analytical expressions have been numerically evaluated and the results obtained through these expressions have been verified using the Monte Carlo simulations. More importantly, long short‐term memory (LSTM)‐based deep learning model has been trained for prediction of outage probability. The model is trained offline and then utilized to predict the values of the outage probability in online mode with mean square error (MSE) and root mean square error (RMSE) of MSE = −45.02 and RMSE = −18.34 dB. [ABSTRACT FROM AUTHOR]

Summary: In this paper, we investigate the effectiveness of incremental relaying (IR)‐based underlay cognitive nonorthogonal multiple access (CNOMA) system with maximal ratio combining (MRC). Considering imperfect successive interference cancelation (i‐SIC), we derive analytical expressions for the outage probabilities experienced by the secondary users (SUs) and the system outage probability of the IR‐CNOMA system. We also derive the analytical expression for the outage probability of far SUs by considering IR‐CNOMA system with MRC. The maximum transmit power constraint of the secondary nodes and the interference threshold constraint of the primary receiver are considered in the analysis. We also evaluate the system throughput of IR‐CNOMA network. We also derive outage and throughput expression for the traditional cooperative relaying‐based CNOMA system (CR‐CNOMA) for the purpose of comparison. We derive analytical expression for the asymptotic outage probability and the asymptotic system outage probabilities of the SUs of IR‐CNOMA system. Further, we derive expressions for the optimal power allocation (OPA) factor at the secondary source that minimizes the asymptotic system outage probability of the IR‐CNOMA system. Through numerical and simulation investigations, we demonstrate that the system outage probability significantly lowers when the OPA factor is selected based on the criteria outlined in this work. It can be observed from the results that the IR‐CNOMA system outperforms the conventional CR‐CNOMA system in terms of outage probabilities and throughput. The outage probability is further reduced when IR‐CNOMA system with MRC is considered for the far SUs. [ABSTRACT FROM AUTHOR]

By adjusting the propagation environment using reconfigurable reflecting elements, intelligent reflecting surfaces (IRSs) have become potential techniques used to improve the efficiency of wireless communication networks. In IRS-assisted communication systems, accurate channel estimation is crucial for optimizing signal transmission and achieving high spectral efficiency. As mobile data traffic continues to surge and the demand for high-capacity and low-latency wireless connectivity grows, IRSs are becoming pivotal technologies in the development of next-generation communication networks. IRSs offer the potential to revolutionize wireless propagation environments, improving network capacity and coverage, particularly in high-frequency wave scenarios where traditional signals encounter obstacles. Amidst this evolving landscape, machine learning (ML) emerges as a powerful tool to harness the full potential of IRS-assisted communication systems, particularly given the escalating computational complexity associated with deploying and operating IRSs in dynamic environments. This paper presents an overview of preliminary results for IRS-assisted communication using recurrent neural networks (RNNs). We first implement single- and double-layer LSTM, BiLSTM, and GRU techniques for an IRS-based communication system. In the next phase, we explore a hybrid approach, combining different RNN techniques, including LSTM-BiLSTM, LSTM-GRU, and BiLSTM-GRU, as well as their reverse configurations. These RNN algorithms were evaluated with respect to bit error rate (BER) and symbol error rate (SER) for IRS-enhanced communication. According to the experimental results, the BiLSTM double-layer model and the BiLSTM-GRU combination demonstrated the highest BER and SER accuracy compared to other approaches. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) is revolutionizing multiple-input-multiple-output (MIMO) technology, making it a promising contender for the coming sixth-generation (6G) and beyond-fifth-generation (B5G) networks. However, the detection process in MIMO systems is highly complex and computationally demanding. To address this challenge, this paper presents an optimized AI-based signal detection method known as AIDETECT-2 which is based on feed forward neural network (FFNN) for MIMO systems. The proposed AIDETECT-2 network model demonstrates superior efficiency in signal detection in comparison with conventional and AI-based MIMO detection methods, particularly in terms of symbol error rate (SER) at various signal-to-noise ratios (SNR). This paper thoroughly explores various signal detection aspects using FFNN, including the design of system architecture, preparation of data, training processes of the network model, and performance evaluation. Simulation results show that the proposed model demonstrates a significant performance improvement ranging between 13.75% to 99.995% better SER compared to the best conventional method and also achieved between 56.52% to 97.69 better SER compared to benchmark AI-based MIMO detectors at 20 dB SNR for given MIMO scenarios respectively. It also presented the computational complexity analysis of different conventional and AI-based MIMO detectors. We believe that this optimized AI-based network model can serve as a comprehensive guide for deploying deep-learning (DL) neural networks for signal detection in the forthcoming 6G wireless networks. [ABSTRACT FROM AUTHOR]

Color shift keying is a modulation scheme for visible light communication that uses fixtures with three or more narrow-spectral light-emitting diodes to transmit data while fulfilling the primary function of illumination. When this modulation is used indoors, the reflectivity of the walls strongly affects the inter-channel interference and illumination quality. In this paper we present an indoor channel model that takes into account multi-wavelength propagation. This model is available as an open-source Python package. The model calculates the inter-channel interference, illuminance, correlated color temperature, and color rendering index at the receiver position. The Python package includes a module for estimating the symbol error rate. To validate the model, we computed the received power at each color photodetector for four different indoor scenarios. The model demonstrated a color rendering index of less than 15 when using IEEE-based color shift keying and non-uniform illumination on a horizontal plane. The simulation determined the required luminous flux to achieve a symbol error rate of less than 10 − 5 when the photodetector is at the center of the indoor space and vertically below the light source. To maintain a symbol error rate less than 10 − 5 , the luminous flux increases when the photodetector is displaced in a diagonal direction from the center of the plane. [ABSTRACT FROM AUTHOR]

Vertical cavity surface-emitting laser (VCSEL)-based optical interconnects (OI) are crucial for high-speed data transmission in data centers, supercomputers, and vehicles, yet their performance is challenged by harsh and fluctuating thermal conditions. This paper addresses these challenges by integrating an ordinary differential equation (ODE) solver within the VCSEL communication chain, leveraging the adjoint method to enable effective gradient-based optimization of pre-equalizer weights. We propose a machine learning (ML) approach to optimize feed-forward equalizer (FFE) weights for VCSEL transceivers, which significantly enhances signal integrity by managing inter-symbol interference (ISI) and reducing the symbol error rate (SER). [ABSTRACT FROM AUTHOR]

Security postulates of visible light communication (VLC) is a paramount area of consideration due to its deployment in military, businesses, and residential establishments. Optical code division multiplexing (OCDMA) is prominent multiples access technique to serve multiple users and offer better security as compared to other available techniques such as wavelength and time division multiplexing (TDM). Wavelength conversion, multicode keying, optical logic gates, and quantum key distribution are some of the widely used security enhancement techniques but come at high cost and greater complexity. Zero cross correlation codes (ZCC) with integration of time dimension is an ultimate solution to the complex security improvement techniques but conventional two dimensional (2D) ZCC codes has an utmost issue of adjacent weights (W) and time (t) in the code which can be easily decoded by eavesdropper. Therefore, in this work, a novel weight managed ZCC (WMZCC) OCDMA code is presented with the non-adjacent W and t in the code matrix for making authentic information decoding difficult. Proposed 2D-WMZCC codes are investigated for 5 users at 100 Gbps over VLC link length of 5 m using polarization division multiplexed (PDM) quadrature phase shift keying (QPSK) and digital signal processing in terms of log symbol error rate (log SER), Q factor and bit error rate (BER). Further, a detailed comparison of 2D-WMZCC codes is performed with existing 2D diagonal identity matrix (DIM) codes and results revealed that former one exhibits better security than later OCDMA code. [ABSTRACT FROM AUTHOR]

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For the future of sixth-generation (6G) wireless communication, simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) technology is emerging as a promising solution to achieve lower power transmission and flawless coverage. To facilitate the performance analysis of RIS-assisted networks, the statistics of the sum of double random variables, i.e., the sum of the products of two random variables of the same distribution type, become vitally necessary. This paper applies the statistics of the sum of double random variables in the performance analysis of an integrated power beacon (PB) energy-harvesting (EH)-based NOMA-assisted STAR-RIS network to improve its outage probability (OP), ergodic rate, and average symbol error rate. Furthermore, the impact of imperfect successive interference cancellation (ipSIC) on system performance is also analyzed. The analysis provides the closed-form expressions of the OP and ergodic rate derived for both imperfect and perfect SIC (pSIC) cases. All analyses are supported by extensive simulation results, which help recommend optimized system parameters, including the time-switching factor, the number of reflecting elements, and the power allocation coefficients, to minimize the OP. Finally, the results demonstrate the superiority of the proposed framework compared to conventional NOMA and OMA systems. [ABSTRACT FROM AUTHOR]

Non-orthogonal multiple access (NOMA) can be a desirable method since it can utilize resources efficiently to provide larger capacity. Similarly, optical transmission is also becoming popular due to the availability of licence-free large bandwidth and low-cost transceiver implementation. Although optical NOMA system can be promising for long range wireless systems, investigation of its reliability performance is essential for different channel models. In this study, outage probability, channel capacity, symbol error rate expressions, diversity and coding gains for arbitrary number of users are obtained for downlink-NOMA over free space optical links modeled with Málaga distribution. Theoretical results are verified by numerical examples for various scenarios providing useful background for future analyses and designs. [ABSTRACT FROM AUTHOR]

Massive MIMO (mMIMO) is the essential technique for attaining the exponential increase in the data rate needed for future communication systems. These advancements have been significantly supported by progress in VLSI technology, which enables the integration of an enormous number of antennas and the complex signal processing essential for massive MIMO systems on a single chip. This work conducts a comprehensive analysis of the intricacy of seven matrix decomposition techniques for symbol detection in future mMIMO communication systems: ADMM-based infinity norm (ADMIN), Neumann series (NS), Newton iteration (NI), Jacobi iteration (Ja), improved Gauss-Seidel (IGS), conjugate gradient (CG), and QR decomposition (QR), against linear and near-optimal minimum mean square error (MMSE). QR, GS, Ja, and CG belong to linear algebraic methods based on matrix decomposition. MMSE and ADMIN are nonlinear optimization methods; NS and NI are iterative methods. The analysis examines into the complexity of these detection algorithms, considering the symbol error rate, the convergence rate, the initial solution vector, and the correlation factor. Performance evaluations are conducted on 8 and 16-user mMIMO systems with 64 and 128 base station antennas, modulation schemes (32-QAM and 64-QAM), iteration counts (p = 1, 2, 3, 4), correlation factors (α = 0.2, 0.4, and 0.6), and initial solution vectors (zero vector, D−1 and W2−1yMF). The result clearly shows that if the initial solution and number of iterations are chosen properly, the IGS-based linear detector achieves near-optimal performance with a lower computational complexity of O(K2) compared to the nonlinear MMSE-based detector with a computational complexity of O(K3). [ABSTRACT FROM AUTHOR]

Shadowed Beaulieu-Xie (SBX) is a composite fading model suitable for an environment with a random number of non-line-of-sight and line-of-sight signals encountered in the wireless communication system. There are many effects that undergo in the wireless channel that may degrade the performance of the system. Diversity is one popular technique to mitigate the effects of fading. Investigation of the influence of various parameters of SBX fading channels on the performance of dual-branch selection combining (SC) diversity receiver is carried out. In this paper, mathematical expressions for the probability density function (PDF) of the output signal-to-noise ratio of dual-SC diversity receiver are calculated for SBX fading channels. Outage probability and average bit error rate (ABER) for different kinds of modulation methods are obtained using the PDF-based method. A unified ABER expression for coherent and non-coherent modulations for dual-SC diversity receivers over SBX fading channels is also derived. The effect of shadowing and fading parameters on the performance of dual-SC diversity receivers is studied. [ABSTRACT FROM AUTHOR]

In this paper, the performance of a dual-hop mixed radio frequency (RF)/underwater wireless optical communication (UWOC) system with amplifying and forwarding (AF) relaying is investigated. The diversity combining technology were combined with unifying Fisher-Snedecor ( $ \mathcal{F} $ F ), extended generalized- $ {\mathcal{K}} $ K (EGK), and $ \alpha - \mu $ α − μ distribution for atmospheric turbulence in foggy conditions to analyze the probability density function (PDF) of RF links. The UWOC link experiences mixed exponential generalized gamma (EGG) fading. By utilizing diversity combination methods and considering the statistical effects of atmospheric turbulence, random fog, and underwater turbulence, we derive the expression for the PDF of the RF/UWOC system. In addition, the tight asymptotic expression for the outage probability and average bit error rate under high signal-to-noise ratio (SNR) is provided. The analytical expressions are verified by Monte Carlo method, and the effects of channel number on RF/UWOC system performance under various atmospheric, underwater and weather conditions are demonstrated. [ABSTRACT FROM AUTHOR]

In this paper, a model of a wireless receiver based on macro diversity (MD) technique is considered. The system consists of a macro diversity SC receiver (MD SC) that combines the output signals from two micro diversity (mD SC) receivers with L input branches. This approach is used to simultaneously reduce the effects of Weibull short-term fading, Gamma long-term fading, and co-channel interference (CCI) on system performance. In this paper, closed-form expressions for the outage probability (Pout) of the system for the ratio of the signal-to-interference (SIR) at the outputs of the mD SC and the MD SC receiver, were derived. The system Pout of the ratio the signal-to-interference at the output of the MD SC receiver can further be used to calculate the average fading duration (AFD) of the proposed system configuration. Further, we explore the potential of using Large Language Model (LLM)-based trending ChatGPT service to estimate the degree of the Quality of Service (QoS), considering Pout as one of the input variables. Finally, we have compared the proposed method to traditional Weka-based machine learning algorithm in predicting the QoS. [ABSTRACT FROM AUTHOR]

In this work, we investigate the performance of dual-hop hybrid free-space optical/radio frequency (FSO/RF) systems with decode-and-forward relaying, where the FSO link experiences Gamma–Gamma turbulence with pointing errors, while the RF link undergoes Nakagami- m fading. Two scenarios are considered, in the first scenario, a hard-switching (HS) scheme is used for the hybrid system, in which one of the links is active at a time, with high priority for the FSO link, whereas in the second scenario, both the FSO and RF links are active simultaneously and a selection combining (SC) scheme is used at the receiver end. We derive exact analytical expressions for the outage probability and average bit error rate (ABER) in terms of multivariate Fox H functions, and develop Monte Carlo simulations for validation. In the numerical results, we compare the performance of the two scenarios with the dual-hop FSO system. This comparison shows a respectable improvement in the system's performance when the hybrid transmission technique is exploited over the dual-hop system. Moreover, the hybrid system with the SC scheme shows superior performance when compared to the system with the HS scheme in terms of the ABER. [ABSTRACT FROM AUTHOR]

Vehicle-to-everything (V2X) is considered a key factor in driving the future development of intelligent transport, which requires high-quality communication and fast sensing of vehicle information in high-speed mobile scenarios. However, high-speed mobility makes the wireless channel change rapidly, which requires frequent channel estimation and channel feedback between a vehicle and the roadside unit (RSU), resulting in an increase in communication overhead. At the same time, the high maneuverability of vehicles leads to frequent switching and misalignment of communication beams, so the RSU must have better beam prediction and tracking capabilities. To address this problem, this paper proposes an adaptive frame structure design scheme for sensing-assisted downlink (DL) communication. The basic idea of the scheme involves analyzing the communication model during the vehicle's movement. This analysis aims to establish a theoretical relationship between the Symbol Error Rate (SER) and the following two key factors: the vehicle's starting position and the distance it travels across. Subsequently, the scheme leverages the vehicle's position data, as detected by the RSU, to calculate the real-time SER for DL communication. The SER threshold is set based on the requirements of DL communication. If the real-time SER is below this threshold, channel estimation becomes unnecessary. This decreases the frequency of channel estimation and frees up time and frequency resources that would otherwise be occupied by channel estimation processes within the frame structure. The design of an adaptive frame structure, as detailed in the above scheme, is presented. Furthermore, the performance of the proposed method is analyzed and compared with that of the traditional communication protocol frame structure and the beam prediction-based frame structure. The simulation results indicate that the communication throughput of the proposed method can be improved by up to 6% compared with the traditional communication protocol frame structure while maintaining SER performance. [ABSTRACT FROM AUTHOR]

This study examines how well a heterogeneous dual-hop terrestrial radio frequency and underwater acoustic downlink system maintain confidentiality. It includes an RF source, an intermediate decode-and-forward relay, an underwater multi-hydrophone destination, and a nearby eavesdropper. Eavesdropper overhears underwater acoustic signal transmitted by the relay. RF and underwater acoustic links undergo Nakagami-m and Rayleigh fading, respectively. Due to the propagation delay of underwater scenario, both destination and eavesdropper links are associated with outdated channel state information which also employs maximal-ratio combining. The closed form expressions of secrecy outage probability, strictly positive secrecy capacity, and intercept probability are derived. Monte-Carlo simulations are obtained to certify the analytical expressions. [ABSTRACT FROM AUTHOR]

An end-to-end testbed for In-phase and Quadrature (I/Q) Imbalance (IQI) communication systems based on Software-Defined Radio (SDR) is presented. The scenario under consideration is a Single-Input–Single-Output (SISO) single-carrier communication where the transmitter is heavily affected by IQI, whose effects are mitigated through digital signal processing at the receiver. The presented testbed is highly configurable, enabling the testing of different communication and IQI parameters. Crucial insights into the practical implementation of IQI mitigation techniques, specifically through the use of asymmetric signaling at the receiver, are provided. Initially, a detailed description of the mathematical framework is given. This framework serves as the foundation for the subsequent discussion on system implementation, effectively bridging the gap between research on IQI mitigation and its practical application in single-carrier architectures. Over-The-Air (OTA) Symbol Error Rate (SER) measurements for different constellations validate the receiver design and implementation. The source code of the presented testbed is publicly available. [ABSTRACT FROM AUTHOR]

Distributed in-network processing has garnered much attention due to its capability to estimate the unknown parameter of interest from noisy measurements based on a set of cooperating sensor nodes. In previous studies, distributed in-network processing mainly focused on short-distance communication systems, wherein sensor nodes collect certain parameters of interest within their maximum communication distance. In addition, the estimation of certain parameter vectors of interest from noisy measurements, relying heavily on training signals, is achieved with a non-blind distributed estimation algorithm. However, in some applications, acquiring knowledge of training signals beforehand is difficult. Therefore, it is necessary to perform distributed estimation algorithms for receivers without training signals, a concept known as blind distributed estimation. In this paper, the generalized Sato algorithm is used to design the blind equalizer for the signal estimation. In addition, we consider extending the short-distance communication system to a long-distance communication system for an unmanned aerial vehicle (UAV) cooperating with sensor nodes in the wireless sensor network (WSN). In this scenario, the data signal is transmitted from a UAV to the WSN and is received by sensor nodes. However, the performance of the blind equalizer is susceptible to the transmission channel in long-distance communication systems. Here, we present a network topology reconfiguration approach to address the issue of distributed blind equalization. The objective of the proposed method is to discard the influence of ill-channels on the other sensor nodes by detecting ill-channels and redesigning the sensor node weights. Through computer simulation experiments, we evaluated the performance of the blind equalizer using the average mean square error (MSE) and average symbol error rate (SER). In the results of the computer simulation experiments, the blind equalizer using the proposed method outperformed the conventional methods in terms of prediction accuracy and convergence speed. [ABSTRACT FROM AUTHOR]

A flexible radio waveform, generalised frequency division multiplexing (GFDM) allows for significant degrees of freedom in adjusting the number of time slots, subcarriers, and pulse shaping filters. The GFDM is one of the multi-carrier techniques that has been proposed to achieve 5G requirements. Initially, this study discusses about the derivation of novel analytical expression of symbol error rate under α - μ fading channel using the GFDM system. The proposed derivation includes Rayleigh, Nakagami-m, and Nakagami-q fading channels as special cases for different α and μ values. Further, a simulation test-bed has been developed in MATLAB to access the simulation results and they are in good agreement with the derived theoretical results for various simulation parameters such as different roll-off factors, modulation orders and various fading parameters. [ABSTRACT FROM AUTHOR]

The authors investigate the performance of an original multifunction system with two in‐band full‐duplex capable joint radar, communications and security (JRCS) transceivers in the presence of an eavesdropper. The system concept can be generalised to a network of more than two JRCS transceivers and multiple eavesdroppers, despite the present study focusing on the three‐node scenario. By combining a bandlimited pseudonoise waveform with a data‐containing orthogonal frequency‐division multiplexing (OFDM) waveform, the authors are able to ensure a certain jamming‐to‐signal power ratio (JSR) at the eavesdropper, whilst ideal synchronisation ensures that jamming causes no deterioration to their own data transfer or radar sensing performance as it is possible to remove just the known pseudonoise waveform. To validate the system, the authors investigate through simulations the OFDM symbol error rates of all the receivers, radar target signal‐to‐interference‐plus‐noise power ratios as well as receiver operating characteristic curves, and eavesdropper's detection signal‐to‐noise power ratios through two‐branch receiver cross‐correlation. The results show that already a very low JSR of −20 dB can improve physical‐layer security without a significant increase in friendly symbol error rate or deterioration in radar performance. Additionally, other full‐duplex transceivers potentially occupying the same radio resources improve the secrecy even further. [ABSTRACT FROM AUTHOR]

Two-wave with diffuse power (TWDP) is one of the most promising distributions for describing multipath fading in the emerging millimeter-wave (mmWave) band. However, traditional error performance analysis in these channels is mostly based on the approximate expressions, accurate only for specific combinations of TWDP parameters that describe particular channel conditions. Considering the aforementioned, this paper begins with an extensive literature overview of the existing average bit/symbol error probability (ABEP/ASEP) expressions in TWDP channels, revealing the absence of the exact expressions that could be used to accurately evaluate error performance in all channel conditions, for most modulation and diversity techniques. Next, the exact ASEP expressions are derived for M-ary rectangular quadrature amplitude modulation with coherent detection and for M-ary differential phase shift keying modulation. These expressions are then used to derive corresponding computationally simple closed-form asymptotic ASEPs, which accurately evaluate error performance for signal-to-noise ratios (SNR) greater than 30 dB. All the results are verified through Monte-Carlo simulation. [ABSTRACT FROM AUTHOR]

In this paper, the effects of energy harvesting (EH) on an automatic repeat request based cooperative communication network comprised of a source, a relay, and two destination nodes, are investigated in Rayleigh fading channels. The energy of the decode-and-forward relay is provided by EH throughout the radio frequency signal from the source. In the proposed transmission protocol, the source transmits a data packet to the relay and two destination nodes by direct links. If the transmission is successful at both destination nodes, these nodes reply by an acknowledgement (ACK) signal to the source and the relay. Otherwise, there are two alternatives: If the relay has received this data packet successfully and replied by an ACK signal, then it cooperates and transmits the data packet for a second time to two destination nodes. If the relay has failed and replied by a non-acknowledgement signal, the source in this case retransmits this packet to the destination nodes by direct links. First, a broadcast channel is considered where the source transmits the same data packet to the relay and destination nodes. Second, the non-orthogonal multiple access technique is applied to the same network where different packets are sent to each destination node by means of superposition coding. In both cases, the system throughputs are obtained from the derived closed-form expressions for the outage probabilities based on the Markov chain model. All theoretical results are supported by computer simulation results. [ABSTRACT FROM AUTHOR]

Photonic integrated circuits (PIC) devices are impacted by fabrication tolerances and therefore, prior knowledge of such variations could improve the PIC fabrication process and overall yield. This paper presents a method for predicting the fabrication impacts on a telecommunication optical digital to analog converter (oDAC)-based pulse amplitude modulator level four (PAM-4) transmitter as a case study where the certainty of this passive device is subjected to random variation. Our findings allow us to estimate the production yield in a fabrication scenario using the symbol error rate (SER) benchmark and this contributes to the study of the viability of oDAC PAM-4 transmitters to replace conventional electrical digital to analog converter (eDAC) PAM-4 transmitters. [ABSTRACT FROM AUTHOR]

In this paper, we investigate an Internet of Things (IoT) network in severe fading environments, where the source sends some information to the destination. Due to the fading obstacle, the source cannot directly send the information to the destination. To tackle this issue, we consider the communication of IoT networks assisted by multi-hop relaying, where multiple relays can help assist the data transmission from the source to the destination. For the considered IoT networks assisted by multi-hop relaying, we evaluate the system performance by studying the transmission outage probability, where an analytical expression is derived to evaluate the IoT outage. We then evaluate the system performance by studying the transmission achievable data rate, where an analytical expression is provided to evaluate the IoT rate. Finally, we present some experimental results as well as the analytical results to verify the derived expressions for the IoT networks assisted by multi-hop relaying. In particular, the usage of multi-hop relaying can help extend the coverage area of IoT networks effectively. [ABSTRACT FROM AUTHOR]

This paper investigates the symbol error rate (SER) and coverage probability of single reconfigurable intelligent surface (S-RIS) and double reconfigurable intelligent surface (D-RIS) systems operating over Weibull fading channels. In the S-RIS system, the RIS is positioned between the base station and user link, while in the D-RIS system, RIS-1 and RIS-2 are placed near the base station and user respectively. By leveraging the central limit theorem, we derive the statistical parameters of the received signal-to-noise ratio (SNR) and subsequently closed-form expressions for SER and coverage probability of both systems using the moment-generating function. Also, we determine the optimal location of the RISs in D-RIS system from the simulations of SER. Comparative analysis reveals that the D-RIS system exhibits superior error performance and provides better coverage than the S-RIS system, despite having an equal number of reflecting elements. In addition, we provide an energy consumption gain analysis of the D-RIS system. [ABSTRACT FROM AUTHOR]

Filter Bank Multi-Carrier (FBMC) modulation has been recognized as a consistent contender and a possible successor for Orthogonal Frequency Division Multiplexing (OFDM) in 5G and beyond because of its outstanding spectral properties. The channel is assessed in FBMC using pilot-symbol aided channel estimation that provides robust estimates even for severe channel conditions. In the present work, neutralizing the imaginary interference at the pilot positions is focused while estimating the channel. To neutralize the imaginary in terference, multiple auxiliary symbols have been proposed to enhance the throughput and channel capacity. The Iterative Minimum Mean Squared Error (IMMSE) cancellation scheme has been proposed to reduce the interference at the pilot and data positions. Transmission power, Bit Error Rate (BER) and throughput are computed for Filter Bank Multi Carrier (FBMC), OFDM and proven that better system performance is obtained for FBMC. The performance of channel estimation is evaluated through 5G standards and indicates that the usage of multiple auxiliary symbols per pilot leads to better throughput and low Bit Error Rate at low power transmission. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of deep neural network (DNN)-based signal detection in multiple input, multiple output (MIMO), communication systems. MIMO technology plays a critical role in achieving high data rates and improved capacity in modern wireless communication standards like 5G. However, signal detection in MIMO systems presents significant challenges due to channel complexities. This study conducts a comparative analysis of signal detection techniques within both the single input, single output (SISO), and MIMO frameworks. The analysis focuses on the entire transmission chain, encompassing transmitters, channels, and receivers. The effectiveness of three traditional methods—maximum likelihood detection (MLD), minimum mean square error (MMSE), and zero-forcing (ZF)—is meticulously evaluated alongside a novel DNN-based approach. The proposed study presents a novel DNN-based signal detection model. While this model demonstrates superior computational efficiency and symbol error rate (SER) performance compared to more conventional techniques like MLD, MMSE, and ZF in the context of a SISO system, MIMO systems face some challenges in outperforming the conventional techniques specifically in terms of computation times. This complexity of MIMO systems presents challenges that the current DNN design has yet to fully address, indicating the need for further developments in wireless communication technology. The observed performance difference between SISO and MIMO systems underscores the need for further research on the adaptability and limitations of DNN architectures in MIMO contexts. These findings pave the way for future explorations of advanced neural network architectures and algorithms specifically designed for MIMO signal-processing tasks. By overcoming the performance gap observed in this work, such advancements hold significant promise for enhancing the effectiveness of DNN-based signal detection in MIMO communication systems. [ABSTRACT FROM AUTHOR]