Timing Synchronization for Upstream Cable OFDMA Signals The most recent broadband dataovercable standard, known as DOCSIS 3.1, introduced orthogonal frequencydivision multiplexing (OFDM) as a major upgrade to improve transmission efficiency. Because OFDM signals are sensitive to synchronization errors, accurate timing recovery is an integral part of a DOCSIS 3.1 system. Many conventional OFDMOFDMA timing synchronization methods cannot be directly applied, as they require the use of specific training signals which are incompatible with DOCSIS 3.1. In this paper, the performance of a modified Schmidl and Cox (Su0026C) timing algorithm is first investigated for DOCSIS 3.1 systems and shown to be unsatisfactory under severe channel conditions. Two novel timing algorithms are proposed which take advantage of the mirrored symmetry of the training signal defined in DOCSIS 3.1. It is demonstrated that both algorithms provide accurate timing estimates even under severe channel conditions and heavy traffic flow. The second algorithm is introduced to eliminate the use of multipliers in the first algorithm, hence reducing the hardware complexity. Data skipping and data truncation are also presented as methods of further reducing the hardware complexity and the corresponding costperformance tradeoff is investigated.

Enhanced Symbol Synchronization for MultiUser High Reliable Dynamic Industrial Wireless Communication Recently, the wireless communication system development driven by the ongoing Industry 4.0 (I40) and Industrial Internet of Thing (IIoT) has been growing enormously. In industrial automation and manufacturing, closedloop control applications are commonly used, which require completely new solutions to achieve ultra high reliability and have stringent requirements on message timing and repetitive packet losses. A novel hardwarebased enhanced preambleaided OFDM frame detection and frequency offset estimation aiming at the high reliability and low packet loss rate is introduced in this work. With the introduced carrier frequency offset estimation, key highlights of our work are a) multiuser support, b) low hardware overhead, and c) lower packet loss rate.