Joint Channel Estimation and Synchronization Techniques for Time-Interleaved Block-Windowed Burst OFDM

Abstract

From a conceptual perspective, beyond-5G technologies promise to deliver very low latency, even higher data rates, and ultrareliable connections for future generations of communication systems. Modulation schemes based on orthogonal frequency-domain multiplexing (OFDM) can accommodate these requirements for wireless systems. Several hybrid OFDM-based systems, such as the time-interleaved block-windowed burst–OFDM (TIBWB–OFDM), are capable of achieving even better spectral confinement and power efficiency. This paper addresses the implementation of the TIBWB–OFDM system in more realistic and practical wireless link scenarios by addressing the challenges of proper and reliable channel estimation and frame synchronization. We propose to incorporate a preamble formed by optimal correlation training sequences such as the Zadoff–Chu (ZC) sequences. The added ZC preamble sequence is used to jointly estimate the frame beginning through signal-correlation strategies and a threshold decision device, and acquire channel-state information (CSI) by employing estimators on the basis of the preamble sequence and transmitted data. The employed receiver estimators show that it is possible to detect the TIBWB–OFDM frame beginning and highlight the robustness of the TIBWB–OFDM technique to imperfect channel estimations by showing that it can provide comparatively close BER performance to the one where the CSI is perfectly known.

Adaptive threshold for discrete fourier transform‐based channel estimation in generalized frequency division multiplexing system

“…The proposed method required two additional N ‐point Fourier transformations with a complexity of for each for the DFT‐based channel estimation in comparison to the LS method, which involved only simple vector division [9, 15]. Only straightforward additions and multiplications were required for the threshold calculation and SINR estimation.…”

“…Even though LMMSE provides satisfactory results, its performance comes at the cost of higher complexity in practice that offsets the lowlatency advantage. In addition, an approach using the adaptive filter has also been investigated to address the issue [14,15]. Satisfactory performance could be achieved with the aid of a training sequence, which adds up both complexity and resource consumption, thus leading to lower throughput.…”

Capturing synchronization with complexity measure of ordinal pattern transition network constructed by crossplot

“…Since Huygens first described the phenomenon of synchronization when observing the coupling of a nearby pendulum in 1665 [1], the synchronization between dynamical systems has been one of the main research directions of nonlinear dynamics. Synchronization and related phenomena have been observed not only in engineering and economic systems, but also in biological and physiological systems [2][3][4][5][6]. However, despite the fact that synchronization is a ubiquitous phenomenon, the detection and quantification of synchronization can be a non-trivial task, as the phenomenon can manifest itself in many different ways.…”