Design of a SIMO Deep Learning-Based Chaos Shift Keying (DLCSK) Communication System

This paper brings forward a Deep Learning (DL)-based Chaos Shift Keying (DLCSK) demodulation scheme to promote the capabilities of existing chaos-based wireless communication systems. In coherent Chaos Shift Keying (CSK) schemes, we need synchronization of chaotic sequences, which is still practically impossible in a disturbing environment. Moreover, the conventional Differential Chaos Shift Keying (DCSK) scheme has a drawback, that for each bit, half of the bit duration is spent sending non-information bearing reference samples. To deal with this drawback, a Long Short-Term Memory (LSTM)-based receiver is trained offline, using chaotic maps through a finite number of channel realizations, and then used for classifying online modulated signals. We presented that the proposed receiver can learn different chaotic maps and estimate channels implicitly, and then retrieves the transmitted messages without any need for chaos synchronization or reference signal transmissions. Simulation results for both the AWGN and Rayleigh fading channels show a remarkable BER performance improvement compared to the conventional DCSK scheme. The proposed DLCSK system will provide opportunities for a new class of receivers by leveraging the advantages of DL, such as effective serial and parallel connectivity. A Single Input Multiple Output (SIMO) architecture of the DLCSK receiver with excellent reliability is introduced to show its capabilities. The SIMO DLCSK benefits from a DL-based channel estimation approach, which makes this architecture simpler and more efficient for applications where channel estimation is problematic, such as massive MIMO, mmWave, and cloud-based communication systems.

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A Novel Multiple-Access Correlation-Delay-Shift-Keying

International Journal of Bifurcation and Chaos ◽

10.1142/s0218127417500250 ◽

2017 ◽

Vol 27 (02) ◽

pp. 1750025 ◽

Cited By ~ 1

Author(s):

J. Y. Duan ◽

G. P. Jiang ◽

H. Yang

Keyword(s):

Fading Channels ◽

Multiple Access ◽

Additive White Gaussian Noise ◽

Reference Signal ◽

Multipath Fading ◽

Signal Interference ◽

Shift Keying ◽

Chaos Shift Keying ◽

Differential Chaos Shift Keying ◽

Ber Performance

In Correlation-Delay-Shift-Keying (CDSK), the reference signal and the information-bearing signal are added together during a certain time delay. Because the reference signal is not strictly orthogonal to the information-bearing signal, the cross-correlation between the adjacent chaotic signal (Intra-signal Interference, ISI) will be introduced into the demodulation at the receiver. Therefore, the Bit-Error Ratio (BER) of CDSK is higher than that of Differential-Chaos-Shift-Keying (DCSK). To avoid the ISI component and enhance the BER performance of CDSK in multiuser scenario, Multiple-Access CDSK with No Intra-signal Interference (MA-CDSK-NII) is proposed. By constructing the repeated chaotic generator and applying the Walsh code sequence to modulate the reference signal, in MA-CDSK-NII, the ISI component will be eliminated during the demodulation. Gaussian approximation method is adopted here to obtain the exact performance analysis of MA-CDSK-NII over additive white Gaussian noise (AWGN) channel and Rayleigh multipath fading channels. Results show that, due to no ISI component and lower transmitting power, the BER performance of MA-CDSK-NII can be better than that of multiple-access CDSK and Code-Shifted Differential-Chaos-Shift-Keying (CS-DCSK).

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PERFORMANCE OF FREQUENCY-MODULATED DIFFERENTIAL-CHAOS-SHIFT-KEYING COMMUNICATION SYSTEM OVER MULTIPATH FADING CHANNELS WITH DELAY SPREAD

International Journal of Bifurcation and Chaos ◽

10.1142/s0218127405014465 ◽

2005 ◽

Vol 15 (12) ◽

pp. 4027-4033 ◽

Cited By ~ 4

Author(s):

YONGXIANG XIA ◽

CHI K. TSE ◽

FRANCIS C. M. LAU ◽

GÉZA KOLUMBÁN

Keyword(s):

Fading Channels ◽

Communication System ◽

Communication Systems ◽

Multipath Fading ◽

Equivalent Model ◽

Delay Spread ◽

Error Performance ◽

Multipath Fading Channels ◽

Shift Keying ◽

Chaos Shift Keying

Multipath performance is an important consideration for chaos-based communication systems. In this letter, the performance of the FM-DCSK communication system over multipath fading channels is evaluated by computer simulations. Both Rayleigh fading and Ricean fading are considered, and the low-pass equivalent model of the FM-DCSK system is used in the simulation. Based on this model, we analyze the bit error performance of the system and the effects of system parameters on the bit-error performance.

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Design and Performance Analysis of a Multi-Carrier M-Ary DCSK System with Multilevel Code-Shifted Modulation Based on Fractional-Order Chaos

Electronics ◽

10.3390/electronics10192343 ◽

2021 ◽

Vol 10 (19) ◽

pp. 2343

Author(s):

Ya-Qiong Jia ◽

Guo-Ping Jiang ◽

Hua Yang ◽

Bin Yu ◽

Ming-Di Du

Keyword(s):

Fading Channels ◽

Fractional Order ◽

Rayleigh Fading ◽

Additive White Gaussian Noise ◽

Reference Signal ◽

Receiver Side ◽

Improve Performance ◽

Shift Keying ◽

And Performance ◽

Chaos Shift Keying

A new fractional-order multi-carrier M-ary differential chaos shift keying system with multilevel code-shifted modulation (MC-MDCSK-MCS) is presented in this paper. The proposed system adopts multiple subcarriers, on which multiple MCS-MDCSK-modulated signals are transmitted simultaneously. Moreover, M-ary modulation has been combined with the proposed system to achieve a higher bit rate. On the receiver side, the recovered reference signal is first averaged and then used for MCS-MDCSK demodulation, which helps improve performance. We analyze the bit error rate (BER) of the proposed system and verify our theoretical derivations with the simulation results over additive white Gaussian noise (AWGN) and Rayleigh fading channels. Finally, related comparisons are completed, which show that the MC-MDCSK-MCS system is excellent and promising.

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Machine Learning-Based 5G-and-Beyond Channel Estimation for MIMO-OFDM Communication Systems

Sensors ◽

10.3390/s21144861 ◽

2021 ◽

Vol 21 (14) ◽

pp. 4861

Author(s):

Ha An Le ◽

Trinh Van Van Chien ◽

Tien Hoa Nguyen ◽

Hyunseung Choo ◽

Van Duc Nguyen

Keyword(s):

Neural Network ◽

Machine Learning ◽

Deep Learning ◽

Channel Estimation ◽

Network Architecture ◽

Communication Systems ◽

Short Term Memory ◽

Estimation Error ◽

Critical Role ◽

Estimation Methods

Channel estimation plays a critical role in the system performance of wireless networks. In addition, deep learning has demonstrated significant improvements in enhancing the communication reliability and reducing the computational complexity of 5G-and-beyond networks. Even though least squares (LS) estimation is popularly used to obtain channel estimates due to its low cost without any prior statistical information regarding the channel, this method has relatively high estimation error. This paper proposes a new channel estimation architecture with the assistance of deep learning in order to improve the channel estimation obtained by the LS approach. Our goal is achieved by utilizing a MIMO (multiple-input multiple-output) system with a multi-path channel profile for simulations in 5G-and-beyond networks under the level of mobility expressed by the Doppler effects. The system model is constructed for an arbitrary number of transceiver antennas, while the machine learning module is generalized in the sense that an arbitrary neural network architecture can be exploited. Numerical results demonstrate the superiority of the proposed deep learning-based channel estimation framework over the other traditional channel estimation methods popularly used in previous works. In addition, bidirectional long short-term memory offers the best channel estimation quality and the lowest bit error ratio among the considered artificial neural network architectures.

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Study of 5G-NR-MIMO Links in the Presence of an Interferer

Electronics ◽

10.3390/electronics10060732 ◽

2021 ◽

Vol 10 (6) ◽

pp. 732

Author(s):

Avner Elgam ◽

Yael Balal ◽

Yosef Pinhasi

Keyword(s):

Mobile Networks ◽

Communication Systems ◽

Multiple Input Multiple Output ◽

Local Area ◽

Maximum Energy ◽

Base Station ◽

Small Cells ◽

Diversity Coding ◽

Shift Keying ◽

Input Multiple Output

Many communication systems are based on the Multiple Input, Multiple Output (MIMO) scheme, and Orthogonal Space–time Block Transmit diversity Coding (OSTBC), combined with Maximal Ratio Receive Combining (MRRC), to create an optimal diversity system. A system with optimal diversity fixes and optimizes the channel’s effects under multi-path and Rayleigh fading with maximum energy efficiency; however, the challenge does not end with dealing with the channel destruction of the multi-path impacts. Susceptibility to interference is a significant vulnerability in future wireless mobile networks. The 5th Generation New Radio (5G-NR) technologies bring hundreds of small cells and pieces of User Equipment (UE) per indoor or outdoor local area scenario under a specific Long Term Evolution (LTE)-based station (e-NodeB), or under 5G-NR base-station (g-NodeB). It is necessary to study issues that deal with many interference signals, and smart jammers from advanced communication equipment cause deterioration in the links between the UE, the small cells, and the NodeB. In this paper, we study and present the significant impact and performances of 2×2 Alamouti Phase-Shift Keying (PSK) modulation techniques in the presence of an interferer and a smart jammer. The destructive effects affecting the MIMO array and the advanced diversity technique without closed-loop MIMO are analyzed. The performance is evaluated in terms of Bit Error Rate (BER) vs. Signal to Interference Ratio (SIR). In addition, we proved the impairment of the orthogonal spectrum assumption mathematically.

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Design and Performance Analysis of MISO-SRMR-DCSK System over Rayleigh Fading Channels

International Journal of Antennas and Propagation ◽

10.1155/2018/6387317 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10

Author(s):

Gang Zhang ◽

Yi man Hao ◽

Tian qi Zhang

Keyword(s):

Performance Analysis ◽

Fading Channels ◽

Rayleigh Fading ◽

Perfect Match ◽

Rayleigh Fading Channels ◽

Major Drawback ◽

Shift Keying ◽

And Performance ◽

Chaos Shift Keying ◽

Differential Chaos Shift Keying

The major drawback of the differential chaos shift keying (DCSK) system is that equal time and energy are spent on the reference and data signal. This paper presents the design and performance analysis of a short reference multifold rate DCSK (SRMR-DCSK) system to overcome the major drawback. The SRMR-DCSK system is proposed to enhance the data rate of the short reference differential chaos shift keying (SR-DCSK) system. By recycling each reference signal in SR-DCSK, the data slot carries N bits of data and by P times. As a result, compared with SR-DCSK, the proposed system has a higher data transmission rate and evaluates the energy efficiency with respect to the conventional DCSK system. To further improve the bit-error-rate (BER) performance over Rayleigh fading channels, the multiple-input single-output SRMR-DCSK (MISO-SRMR-DCSK) is also studied. The BER expression of the proposed system is derived based on Gaussian approximation (GA), and simulations in Rayleigh fading channels are performed. Simulation results show a perfect match with the analytical expression.

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Improved Pilot Selection for Channel Estimation of Polar Codes in Wireless 5G

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.b9080.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 4978-4983

Keyword(s):

Channel Estimation ◽

Fading Channels ◽

Communication Systems ◽

Mimo System ◽

Multiple Input Multiple Output ◽

Poor Performance ◽

Polar Codes ◽

Selection Scheme ◽

Polar Code ◽

Pilot Selection

Fading channels learning about polar codes is great prominence. Knowledge of polar codes is very important while they are applied to the wireless communication systems. In fading Channels the communication through channel estimation which is an essential step for communication. The structure is constructed by a set of information bits for both systematic polar code and non-systematic polar code and the information set recognized frozen bits. In fading channels uneven pilot selection scheme and even pilot selection scheme are two pilot selection schemes are considered for polar codes. There is an improvement in decoding performance of polar codes using these selection schemes. In this choosing of coded symbols treated as pilots is a replacement of insertion of pilots. Polar codes have poor performance in fixed domain. So the EPS selection scheme can be active for tracing or channel estimation. The structure of polar code encoding is acapable structure and pilot selection is grave since whole selections cannot use the existing structure again. By conjoining the above advantages, pilot signals are selected without any addition from outside and insertion of pilot symbols impartial to estimation of the channel. Leveraging this, the DM-BS scheme is applyto multiple input multiple output (MIMO) system in frequency selective fading channel.

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Encryption of Analog and Digital signals through Synchronized Chaotic Systems

Chaos Synchronization and Cryptography for Secure Communications - Advances in Information Security, Privacy, and Ethics ◽

10.4018/978-1-61520-737-4.ch018 ◽

2011 ◽

pp. 415-438

Author(s):

Kehui Sun

Keyword(s):

Secure Communication ◽

Communication Systems ◽

Chaotic Sequence ◽

Digital Signals ◽

Encryption Schemes ◽

Shift Keying ◽

Chaos Shift Keying ◽

Sequence Generator ◽

Chaotic Secure Communication ◽

Spreading Spectrum

Chaos is characterized by aperiodic, wideband, random-like, and ergodicity. Chaotic secure communication has become one of the hot topics in nonlinear dynamics since the early 1990s exploiting the technique of chaos synchronization. As distinguished by the type of information being carried, chaos-based communication systems can be categorized into analogy and digital, including four popular techniques such as Chaos Masking, Chaos Shift Keying, Chaos Modulation, and Chaos Spreading Spectrum. In this chapter, the principles of these schemes and their modifications are analyzed by theoretical analysis as well as dynamic simulation. In addition, chaos-based cryptography is a new approach to encrypt information. After analyzing the performances of chaotic sequence and designing an effective chaotic sequence generator, the authors briefly presented the principle of two classes of chaotic encryption schemes, chaotic sequence encryption and chaotic data stream encryption.

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