Uncoded space-time labelling diversity : data rate & reliability enhancements and application to real-world satellite broadcasting.

Enhancing the reliability of wireless links plays an important role in addressing the digital divide between under‐developed and developed nations. Diversity techniques are used in wireless communication to improve link reliability. This article presents a broadcasting system that incorporates space, time, polarization and labeling diversity. The key challenge in incorporating labeling diversity into a system is the design of appropriate bit‐to‐symbol mappers. The latest technique to designing bit‐to‐symbol mappers is to use a genetic algorithm approach, which is applicable to any generic modulation scheme. This article presents a modified genetic algorithm mapper design algorithm based on recent advances in labeling diversity evaluation theory. The proposed system is studied under ideal (uncorrelated) conditions, as well as in the presence of inter‐beam and inter‐antenna inference (correlated conditions). Analytical expressions are presented to model both the correlated and uncorrelated systems, and are verified via Monte Carlo simulations. When compared to the best comparable scheme at a bit‐error‐rate of 10−6$$ 1{0}^{-6} $$ , results show that the proposed system improves performance by ≈$$ \approx $$ 7 dB for a 2×2$$ 2\times 2 $$ 16APSK system configuration, and by ≈$$ \approx $$ 5 dB for both 2×4$$ 2\times 4 $$ 32APSK and 2×2$$ 2\times 2 $$ 64APSK system configurations. Results also show that the proposed system is highly sensitive to correlation at the transmitting node. In particular, transmit‐side correlation degrades link reliability by 4 orders of magnitude for the 2×3$$ 2\times 3 $$ 8APSK configuration studied at 25 dB.

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/ett.4663

A multiple‐input, multiple‐output broadcasting system with space, time, polarization, and labeling diversity

Power Allocation under Given Secret Key Generation Rate for Secure Wireless OFDM Systems

Due to the complexity of wireless communication networks and the open nature of wireless links, complex upper layer network encryption cryptographic algorithms are also difficult to implement effectively in complex mobile wireless communication and interconnection networks, and traditional cryptography-based security policies are gradually not well able to meet the security management needs of today’s mobile Internet information era. In this paper, the physical characteristics of the channel in the wireless channel are extracted and used to generate keys, and then, the keys are negotiated so that the keys generated by the two communicating parties are identical. Then, the generated keys are used by the communicating parties to design the interleaving matrix for encryption of the message. The false bit rate of the system is investigated for the case of an interleaving matrix generated using different quantization methods of keys. The problem of characterizing the encoding and encryption techniques for interleaving keys for the physical layer sensing antenna arrays of wireless channels is studied in depth. The physical layer wireless channel interleaving technique and the wireless channel physical layer encryption technique are organically combined, and a joint interleaving encryption method based on the physical layer key of the wireless channel is designed and used to encrypt and randomize the physical layer data information of the OFDM (Orthogonal Frequency Division Multiplexing) system, which improves the security and reliability of the wireless channel information transmission. The effect of physical layer keys under different physical layer quantization methods on the performance of the wireless channel interleaving encryption algorithm is studied, and the quantization methods of pure amplitude, pure phase, and joint amplitude phase are investigated for the characteristics of wireless physical layer channels.

/pdf/wireless-communication-physical-layer-sensing-antenna-array-3venw9rh4m.pdf

Wireless Communication Physical Layer Sensing Antenna Array Construction and Information Security Analysis

Abstrak 
Keamanan jaringan nirkabel merupakan salah satu hal terpenting dalam sistem komunikasi. Karena sinyal dikirim dari pengirim melalui saluran nirkabel,  tidak hanya penerima yang sah, tetapi juga penyadap dapat menangkap dan menyimpan sinyal informasi dengan mudah. Penelitian ini mengeksplorasi skema keamanan  komunikasi nirkabel dimana skema yang digunakan adalah pengacakan subcarrier. Pemancar dan penerima harus disinkronkan untuk mengembalikan subcarrier ke posisi semula. Sistem ini menggunakan algoritma RSA sebagai sinkronisasi. Teknologi keamanan pengacakan subcarrier  diimplementasikan pada sistem OFDM. Sistem OFDM  diimplementasikan menggunakan perangkat USRP. Hasil yang diperoleh dari penelitian ini membuktikan bahwa teknik keamanan yang digunakan tidak menurunkan kinerja sistem, bahkan dapat mengurangi jumlah kesalahan bit akibat teknik sinkronisasi. Dengan teknik sinkronisasi algoritma RSA, dari jarak pengujian 1 meter, 2 meter, dan 5 meter. Pada jarak 1 meter didapatkan hasil terbaik dengan penurunan error bit dari 19,04% menjadi 0% pada 32-QAM dan penurunan error bit dari 28,57% menjadi 4,76% pada 64-QAM 
Abstract 
Wireless network security is one of the essential things in communication systems. Since the signal is sent from the sender through a wireless channel, the legitimate receiver and eavesdropper can easily capture and store signal information. This study explores a wireless communication security scheme where the scheme used is subcarrier randomization. The transmitter and receiver must be synchronized to return the subcarrier to its original position. This system uses the RSA algorithm as synchronization. Subcarrier randomization security is implemented in OFDM system. OFDM system is implemented using USRP. The results from this study prove that security techniques don't reduce system performance, and can even reduce the number of errors due to synchronization techniques with RSA synchronization technique, with 1meter, 2meters, and 5meters experiments. At 1meter distance is the best result with bit error drop from 19.04% to 0% on 32-QAM and a bit error drop from 28.57% to 4.76% on 64-QAM.

https://eltek.polinema.ac.id/index.php/eltek/article/download/354/236

Implementasi skema pengacakan subcarrier OFDM dengan algoritma RSA pada NI-USRP

The authors incorporate Alamouti space-time block coded orthogonal frequency division multiplexing (OFDM) with signal space diversity (SSD) in order to significantly strengthen the physical layer security of the communication network The coordinate interleaving step of SSD is performed amongst OFDM subcarriers, according to distinct strategies that make the correlation coefficients between the subcarrier channel gains equal to zero The proposed system model can improve the security by enabling a legitimate user to have much less error than an eavesdropper, even under the worst-case scenario where the unauthorised receiver somehow captures the interleaving strategy compromised by the transmitter and legitimate receiver It is shown that a legitimate user with the introduced scheme can provide up to 14% more performance gain as compared to an unauthorised receiver for a bit error rate (BER) of 10−4 under worst-case scenarios with different parameters An exact closed-form expression of the BER is derived for the legitimate user and shown to match with the simulation results Finally, it is demonstrated that the system is also capable of enhancing the resistance against channel estimation errors at the receiver The proposed system does not require high complexity or additional bandwidth or time resources

https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/iet-com.2019.0542

Improving physical layer security in Alamouti OFDM systems with subcarrier coordinate interleaving

In this work, signal space diversity (SSD) is incorporated into a zero-forcing multiple-input multiple-output system with various numbers of transmit and receive antennas. We assume that the number of antennas at both ends is equal and the channel state information is only available at the receiver. The performance of the proposed system is studied under a slow flat Rayleigh fading channel scenario with correlated transmit antennas and uncorrelated receive antennas. We adopt different realistic transmit antenna correlation models. A number of different component interleaving strategies are compared for these correlation models. It is shown that the error performance of the system can be significantly improved by making use of SSD with only a negligible increase in complexity and no extra use of bandwidth/time resources.

Performance of zero-forcing MIMO systems with signal space diversity under transmit antenna correlation

We combine multiple-input multiple-output zero-forcing receive beamforming (ZFRBF) with time and spatial component interleaved signal space diversity (SSD) and analyze the system’s error performanc...

Analysis and FPGA Implementation of Zero-Forcing Receive Beamforming with Signal Space Diversity under Different Interleaving Techniques

In this work, we have combined an Alamouti spacetime block coded orthogonal frequency division multiplexing (OFDM) system with signal space diversity (SSD) in order to improve the physical layer security of a communication network under a Nakagami-m fading channel. Coordinate interleaving (CI) operation of the SSD technique is realized over the OFDM subcarriers. It is shown that various CI strategies can be used to make the correlation coefficients between the OFDM subcarrier channel gains equal to zero. The simulation results reveal that the legitimate user has a much better bit error rate performance than the eavesdropper even under the worst-case scenario where the eavesdropper somehow captures the CI strategy used between the transmitter and authorized receiver.

Enhancement of Physical Layer Security in Alamouti OFDM Systems over Nakagami-m Fading Channels

Non-orthogonal multiple access (NOMA) is expected to be one of the fundamental technologies of the upcoming 6G standard. This is mainly due to NOMA's potential in enabling all the users to utilize the same frequency band and the same time slot. In this paper, NOMA is implemented in a multiple-input multiple-output wireless communication system. By implementing zero-forcing V-BLAST algorithm into NOMA, spectral efficiency is improved, and successive interference cancellation is carried out. To perform optimum ordering, receive antennas’ signatures are compared and which signal to be decoded first is determined. Outage probability results of the system with optimum ordering and the same system without ordering are compared. In this way, a 3 dB gain is shown to be attained in terms of signal-to-noise ratio.

Mustafa Anil Resat

Papers

Improving physical layer security in Alamouti OFDM systems with subcarrier coordinate interleaving

Performance of zero-forcing MIMO systems with signal space diversity under transmit antenna correlation

Analysis and FPGA Implementation of Zero-Forcing Receive Beamforming with Signal Space Diversity under Different Interleaving Techniques

Enhancement of Physical Layer Security in Alamouti OFDM Systems over Nakagami-m Fading Channels

Non-orthogonal multiple access with v-blast under optimum ordering