Showing papers on "SC-FDE published in 2023"
TL;DR: In this paper , a decision-directed successive interference cancellation (DDSIC) based on frequency domain minimum-domain minimum-mean-square-error (MMSE) equalization was proposed for practical Faster-than-Nyquist (FTN) systems.
Abstract: Faster-than-Nyquist (FTN) signaling can improve spectral efficiency and enable high-speed transmission for next-generation communication systems. One of the most significant challenges in FTN transmission is how to remove the inter-symbol interference (ISI). In this paper, we propose a novel decision-directed successive interference cancellation (DDSIC) based on frequency-domain minimum-mean-square-error (MMSE) equalization for practical FTN systems. To reduce the computational complexity, the detection process is performed frame-by-frame in the frequency domain. In addition, we derive the theoretical bit error rate (BER) expression for each iteration in DDSIC as well as the BER lower bound for M -ary quadrature amplitude modulated FTN systems. The simulation results verify the theoretical analyses and demonstrate that our proposed method enables lower complexity and better performance compared with state-of-the-art methods.
TL;DR: In this article , a single carrier frequency domain equalization (SC-FDE) method combining the benefits of Feher-patented quadrature phase shift keying (FQPSK) modulation is raised to solve the problem of inter-symbol interference.
Abstract: Severe multi-path effects in the process of high-speed data transmission cause inter-symbol interference (ISI). The single carrier frequency domain equalization (SC-FDE) method combining the benefits of Feher-patented quadrature phase shift keying (FQPSK) modulation is raised to solve this problem, including the constant envelope, high spectrum efficiency, and insensitivity to nonlinear distortion. Furthermore, a fractionally spaced frequency domain equalization (FS-FDE) system based on FQPSK modulation is modeled based on the proposed algorithm. Simulation results confirm the superior performance of the proposed model on erasing ISI, comparing to the symbol-spaced FDE (SS-FDE) system based on FQPSK modulation and the FS-FDE system based on QPSK modulation.
TL;DR: In this article , an amplify-and-forward (AF) relaying technique that employs phase dithering and intentional delay within single carrier-frequency domain equalizer (SC-FDE) systems was proposed.
Abstract: This paper introduces an amplify-and-forward (AF) relaying technique that employs phase dithering and intentional delay within single carrier-frequency domain equalizer (SC-FDE) systems. The proposed relaying technique aims to increase the gain of both frequency diversity and time diversity in slow fading channels. To achieve this, the proposed technique introduces random phase rotation and random intentional delay. The relaying scenario assumes two-hop communication with relaying between the source and destination. It is assumed that many nodes are densely distributed, allowing for many relay nodes to participate in relaying. To verify the performance through computer simulation, the number of relays is 1, 2, 3, 5, 15, and 25, and three modulation coding schemes (MCSs) are considered: QPSK with R=1/3, 16QAM with R=3/4, and 8PSK with R=7/8. The simulation results demonstrate that the proposed relaying technique improves the bit error ratio (BER) performance. The performance improves as the number of relays increases.
21 Mar 2023
TL;DR: In this paper , a new equalization scheme for aeronautical mobile communication based on MMSE and residual intersymbol interference cancellation (MMSE-RISIC) is proposed.
Abstract: Abstract Under the condition of slow fading time-varying multipath channel with low rice factor, it is difficult to make effective use of signal energy, therefore, the traditional Minimum Mean Squared Error (MMSE) technique cannot effectively reduce the bit error rate. To solve the above problem, we proposes a new equalization scheme for aeronautical mobile communication based on MMSE andresidual intersymbol interference cancellation (MMSE-RISIC), firstly, the hard decision signal is modified to obtain the reconstruction signal of frequency domain, and then further decision is made according to the time domain error. Its essence is to modify the channel to make the estimated channel closer to the real channel. The simulation results show that the SNR can be improved by about 2-8dB with the same bit error performance, indicating that the equalization algorithm makes full use of the energy of the multipath component and obtains the signal-to-noise ratio gain.
29 Mar 2023
TL;DR: Aiming at the timing synchronization problem in underwater acoustic single-carrier frequency domain equalization system (SC-FDE), the training sequence and new metric function is constructed by using the well-related Zadoff-Chu (ZC) sequence, and the genetic algorithm is used to optimize the combination structure, which solves the problems of peak platform and false peak interference in the commonly used synchronization methods as discussed by the authors .
Abstract: Aiming at the timing synchronization problem in underwater acoustic single-carrier frequency domain equalization system (SC-FDE), the training sequence and new metric function is constructed by using the well-related Zadoff-Chu (ZC) sequence, and the genetic algorithm is used to optimize the combination structure, which solves the problems of peak platform and false peak interference in the commonly used synchronization methods. Simulation results show that the improved synchronization algorithm is more accurate at the timing point under low signal-to-noise ratio and has high synchronization accuracy.