Erdal Panayırcı

This item is non-discoverable

Panayırcı, Erdal

Name Variants

P., Erdal
Panayirci,E.
Panayirci,Erdal
Erdal Panayırcı
Panayirci E.
Panayırcı,E.
Panayirci, Erdal
P.,Erdal
Erdal, Panayirci
Panayırcı E.
Panayırcı, Erdal
Panayırcı, Erdal
Panayırcı, Erdal

Job Title

Prof. Dr.

Email Address

eepanay@khas.edu.tr

Main Affiliation

Electrical-Electronics Engineering

Status

Former Staff

Sustainable Development Goals Report Points

SDG data could not be loaded because of an error. Please refresh the page or try again later.

Scholarly Output

169

Articles

62

Citation Count

298

Supervised Theses

9 Scholarly Output Search Results

Now showing 1 - 10 of 165

Citation - WoS: 5
Citation - Scopus: 5
Relay-Aided Secure Broadcasting for Vlc
(IEEE, 2018) Arafa, Ahmed; Panayırcı, Erdal; Panayırcı, Erdal; Poor, H. Vincent; Electrical-Electronics Engineering
A visible light communication (VLC) broadcast channel is considered in which a transmitter communicates with two receivers in the presence of an external eavesdropper. Trusted cooperative half-duplex relays are deployed to aid with securing the transmitted data. Transmission is amplitude-constrained to maintain operation within the light emitting diodes (LEDs) dynamic range. Achievable secrecy rate regions are derived under such amplitude constraints for this multi receiver wiretap channel first for direct transmission without the relays and then for cooperative jamming decode-and-forward and amplify-and-forward relaying schemes. Superposition coding with uniform signaling is used for transmission along with secure beamforming at the relays. Superiority of the secure relaying schemes over direct transmission is shown with performance depending on how far the eavesdropper is from the transmitter and the relays.
Citation - Scopus: 12
Spatial Modulation Aided Physical Layer Security for Noma-Vlc Systems
(IEEE-Inst Electrical Electronics Engineers Inc, 2023) Panayırcı, Erdal; Panayırcı, Erdal; Koca, Mutlu; Haas, Harald; Poor, H. Vincent; Electrical-Electronics Engineering
We consider the physical layer security (PLS) problem in multi-user non-orthogonal multiple access (NOMA) enabled multiple-input multiple-output (MIMO) visible light communication systems intercepted by a passive eavesdropper (Eve). We propose a novel transmit precoding scheme based on receive spatial modulation (RSM) to degrade the signal-to-interference-noise ratio (SINR) of Eve by exploiting only the slow-fading characteristics of the visible light channel of the legitimate users (Bobs). The proposed PLS precoder is reinforced with secret parameter exchange with Bobs and a CSI acquisition model is proposed to reduce the PLS algorithm's computational load substantially at the transmitter. The closed-form expressions for the achievable secrecy rates and their upper and lower bounds are derived. Via Monte Carlo simulations, we confirm that Bobs can successfully decode their information in various user configurations while Eve's received SINR is significantly worsened by the jamming signal induced by the proposed precoder with secret key exchange. It is also shown that Eve's bit error rate (BER) is increased to the 0.5-level for almost any position in the considered indoor environment. Finally, we corroborate the derived secrecy expressions by computer simulations and show that the proposed scheme provides PLS for Bobs.
Citation - WoS: 2
Channel Estimation for Dco-Ofdm Based Vlc Systems in the Presence of Clipping Noise
(IEEE, 2020) Bektaş, Ekin Başak; Panayırcı, Erdal; Panayırcı, Erdal; Electrical-Electronics Engineering
Visible Light Communication(VLC) has been considered as a potential access option for 6G wireless systems to solve performance limitation due to bandwidth shortage at radio frequency (RF) band. In VLC system, illumination infrastructure has dual usage at the same time namely illumination and wireless data transmission. DC-Biased optical DCO-OFDM with clipping has been proposed for VLC systems to provide optically power efficient solution and easy implementation. Wireless communication systems generally require estimating and tracking the fading channel in order to detect transmitted data coherently. In this work, we propose a pilot-aided iterative channel estimation algorithm to efficiently estimate the optical channel coefficients of a clipped DCO-OFDM system operating with additive white Gaussian noise (AWGN). The estimation algorithm is capable of improving the channel estimation by making use of pilot symbols with interpolation or using the channel estimate of previous OFDM block to obtain the next estimate for the iterative algorithm. In each iteration, the clipping noise is estimated and compensated in the frequency domain. Simulation results verify that the proposed channel estimation algorithm reduces the bit error rate (BER) and mean-square error (MSE) of channel estimate can be significantly.
Citation - Scopus: 1009
Orthogonal Frequency Division Multiplexing With Index Modulation
(2013) Basar,E.; Panayırcı, Erdal; Aygolu,U.; Panayirci,E.; Poor,H.V.; Electrical-Electronics Engineering
In this paper, a novel orthogonal frequency division multiplexing (OFDM) scheme, called OFDM with index modulation (OFDM-IM), is proposed for operation over frequency-selective and rapidly time-varying fading channels. In this scheme, the information is conveyed not only by $M$-ary signal constellations as in classical OFDM, but also by the indices of the subcarriers, which are activated according to the incoming bit stream. Different low complexity transceiver structures based on maximum likelihood detection or log-likelihood ratio calculation are proposed and a theoretical error performance analysis is provided for the new scheme operating under ideal channel conditions. Then, the proposed scheme is adapted to realistic channel conditions such as imperfect channel state information and very high mobility cases by modifying the receiver structure. The approximate pairwise error probability of OFDM-IM is derived under channel estimation errors. For the mobility case, several interference unaware/aware detection methods are proposed for the new scheme. It is shown via computer simulations that the proposed scheme achieves significantly better error performance than classical OFDM due to the information bits carried by the indices of OFDM subcarriers under both ideal and realistic channel conditions. © 2013 IEEE.
Citation - WoS: 1
Breaking the Performance Gap of Fully and Semisupervised Learning in Electromagnetic Signature Recognition
(Ieee-inst Electrical Electronics Engineers inc, 2024) Panayırcı, Erdal; Wang, Qing; Chen, Luyong; Fu, Guanyang; Liu, Xiaofeng; Dong, Zhicheng; Panayirci, Erdal; Electrical-Electronics Engineering
Intelligent electromagnetic signature recognition is one of the key technologies in Internet of Things (IoT) device connection, which can improve system security and speed up the authentication process. In practical scenarios, as the number of IoT devices increases, electromagnetic features, such as fingerprint and modulation signals also increase substantially. However, since intelligent recognition technology, such as automatic modulation classification (AMC), requires a large amount of labeled data to train the neural network classifier, it is challenging to collect so much labeled data. To address the performance degradation challenges with small training data, we propose an efficient semisupervised electromagnetic recognition framework to break the performance gap with the fully supervised learning scheme. This framework can fully use the unlabeled electromagnetic data collected during the authentication process for self-training to improve the classifier's performance. According to the idea of consistency regularization, we design a signal augmentation method and propose an ensemble pseudolabel design algorithm to improve confidence. Moreover, we perform a convex combination of electromagnetic features to smooth the model decision boundary while generalizing to unknown data distribution regions. Experimental results on the modulated data demonstrate the performance superiority of the proposed algorithm, i.e., use less than 5% of data with no more than 10% performance drop.
Citation - Scopus: 40
Orthogonal Frequency Division Multiplexing With Index Modulation in the Presence of High Mobility
(2013) Basar, Ertugrul; Panayırcı, Erdal; Aygölü, Ümit; Panayırcı, Erdal; Electrical-Electronics Engineering
In this paper a novel orthogonal frequency division multiplexing (OFDM) scheme which is called OFDM with index modulation (OFDM-IM) is proposed for frequency-selective fading channels in the presence of high mobility. In this scheme inspiring from the recently introduced spatial modulation concept for multiple-input multiple-output (MIMO) channels the information is conveyed not only by M-ary signal constellations as in classical OFDM but also by the indices of the subcarriers which are activated according to the incoming bit stream. Different low complexity transceiver structures based on maximum likelihood (ML) detection or log-likelihood ratio (LLR) calculation are proposed. It is shown via computer simulations that the proposed scheme achieves significantly better error performance than classical OFDM. © 2013 IEEE.
Citation - Scopus: 1
Energy-Efficient Design for Ris-Aided Cell-Free Ultra Dense Hetnets
(Institute of Electrical and Electronics Engineers Inc., 2023) Li,B.; Panayırcı, Erdal; Hu,Y.; Dong,Z.; Panayirci,E.; Jiang,H.; Wu,Q.; Electrical-Electronics Engineering
In this article, we investigate the energy efficiency of reconfigurable intelligent surfaces (RISs) aided full-duplex cellfree ultra dense hetNets (CFUDN), which has the advantages of both cell-free massive MIMO (CF-MMIMO) and ultra-dense hetNets (UDN). To maximize the EE of full-duplex CFUDN, users association and clustering, RISs subsurface associations are carefully designed. Then, the phase shift matrix of RISs and transmission power of base stations are jointly optimized. Due to the non-convexity and high complexity of formulated problem, it is extremely difficult to solve this problem. At present, the block coordinate descent (BCD) algorithm is the most commonly used method for joint optimization problems. However, as we all know, the BCD algorithm has some degree of performance loss due to alternate optimization. To overcome this challenging issue, a novel joint optimization framework based on Riemannian product manifolds (RPM) is proposed. © 2023 IEEE.
Citation - WoS: 1
Citation - Scopus: 2
Performance of Mimo Enhanced Unipolar Ofdm With Realistic Indoor Visible Light Channel Models
(Institute of Electrical and Electronics Engineers Inc., 2016) Yeşilkaya, Anıl; Panayırcı, Erdal; Miramirkhani, Farshad; Basar, Ertugrul; Panayırcı, Erdal; Uysal, Murat; Electrical-Electronics Engineering
Visible light communication (VLC) involves the dual use of illumination infrastructure for high speed wireless access. Designing such optical based communication systems realistic indoor optical channel modeling becomes an important issue to be handled. In this paper first we obtain new realistic indoor VL channel characterizations and models in a multiple-input multiple-output (MIMO) transmission scenario using non-sequential ray tracing approach for the channel impulse responses (CIRs). Practical issues such as number of light emitting diode (LED) chips per luminary spacing between LED chips objects inside the room and cabling topology are also investigated. On the other hand since indoor optical channels exhibit frequency selectivity multi-carrier communication systems particularly orthogonal frequency division multiplexing (OFDM) is used to handle the resulting inter-symbol interference in VLC systems. Hence we propose a new MIMO-OFDM based VLC system called MIMO enhanced unipolar OFDM (MIMO-eU-OFDM) by combining MIMO transmission techniques with the recently proposed eU-OFDM scheme. The bit error rate (BER) performance of the proposed system is investigated in the presence of the 2×2 and 4×4 realistic MIMO VLC channels and its BER performance is compared with the reference optical MIMO-OFDM systems. © 2016 IEEE.
Citation - WoS: 0
Citation - Scopus: 0
Partial Power and Rate Adaptation for Mqam/Ofdm Systems Under Cfo
(IEEE, 2014) Dong, Zhicheng; Panayırcı, Erdal; Fan, Pingzhi; Panayırcı, Erdal; Lei, Xianfu; Electrical-Electronics Engineering
In this paper a new partial power and rate adaptation scheme for orthogonal frequency division multiplexing (OFDM) systems is proposed in the presence of carrier frequency offset (CFO). The conventional adaptive scheme is shown to be a special case of the partially adaptive scheme technique which enables the resulting non-convex optimization problem solved in a feasible way. It leads to a solution for optimal power adaptation that maximizes the spectral efficiency of an OFDM system using M-ary quadrature amplitude modulation (MQAM) under average power and instantaneous BER constraints. Closed-form expressions for the average spectral efficiency (ASE) of adaptive OFDM systems are derived. The theoretical results and computer simulations show that the range of the partial adaptation becomes narrow and the performance of constant power and continuous rate is very close to that of the partially adaptive power and continuous rate for higher CFO or high signal noise ratio (SNR) values.
Citation - Scopus: 2
Iterative Channel Estimation For Spatial Modulation Systems Over Fast Fading Channels [hızlı Sönümlemeli Kanallarda Uzaysal Modülasyon Sistemleri için İteratif Kanal Kestirimi]
(IEEE Computer Society, 2014) Acar, Yusuf; Panayırcı, Erdal; Doğati, Hakan; Panayırcı, Erdal; Electrical-Electronics Engineering
Spatial Modulation (SM) based on the use of antenna indices to transmit information in addition to the conventional signal constellations has been recently proposed to solve practical problems encountered in MIMO systems. In the literature estimation of CSI for SM systems is simply investigated by RLS for slow fading channels. However iterative receivers that offer significant performance gains over a non-iterative when the total number of pilot is not sufficient and the channel is fast fading have not been investigated for SM based systems. In this paper it shown that the RLS based receiver has a performance degradation for fast fading channels and a new iterative channel estimation techniques is proposed with the necessary signal model to enhance receiver performance for fast fading channels. Computer simulation results indicate that proposed iterative receiver has a significant performance advantage over the RLS based receiver for time-varying Rayleigh channels. © 2014 IEEE.