Synchronization Methods for Multi-Detector Phased Systems Tatiana Krasik

Аннотация

This article examines synchronization OPEN ACCESS methods for multi-detector phased systems that SUBMITED 19 April 2025 integrate spatially distributed transmit–receive nodes ACCEPTED 22 May 2025 PUBLISHED 14 June 2025 into a single coherent structure. The study's primary aim VOLUME Vol.07 Issue 06 2025 is to determine the technical requirements for temporal, frequency, and phase alignment of the elements, and to CITATION analyze the hardware and algorithmic means for Tatiana Krasik. (2025). Synchronization Methods for Multi-Detector achieving them. The relevance of this work is driven by Phased Systems. The American Journal of Engineering and Technology, 7(06), 124–131. https://doi.org/10.37547/tajet/Volume07Issue06-13 the rapid development of phased arrays and distributed COPYRIGHT radar and astronomical systems, where even tens of © 2025 Original content from this work may be used under the terms picoseconds of desynchronization lead to significant loss of the creative commons attributes 4.0 License. of coherent gain and degradation of spatial resolution. Contemporary network protocols such as IEEE 1588 provide only microsecond-level accuracy, which is insufficient for the often-required budgets on the order of tens of picoseconds; therefore, a multi-level architecture is necessary, combining highly stable reference oscillators, zero-delay hardware buffers, deterministic data-transfer interfaces, and digital correction algorithms. The novelty of this research lies in the comprehensive comparison and integration of four classes of solutions: a distributed clock tree with LVDS and fiber-optic lines and zero-delay PLL buffers; deterministic SYSREF frame distribution according to JESD204B/C; bidirectional microwave wireless exchange with pilot-tone synchronization; and digital corrections via cross-correlation and Kalman-consensus algorithms to compensate residual drifts. A methodology for budgeting phase slip—accounting for source jitter, port trace dispersion, and network delays—is presented, enabling early identification and elimination of design bottlenecks. The key conclusion demonstrates the effectiveness of the multi-level scheme: an external hardware-network loop provides coarse phase alignment and frequency stability at the level of single The American Journal of Engineering and Technology 124 https://www.theamericanjournals.com/index.php/tajet to tens of picoseconds. In contrast, the internal digital an RMS deviation to UTC of about 10 ns [4], which is loop maintains instantaneous coherence with phase sufficient even for low-band radio interferometry. errors of only a few degrees, even when nodes are Third, phase accuracy Δφ: analytical estimates indicate separated by hundreds of meters or during GNSS that a loss of coherent gain of 0.5 dB occurs at a random outages. Systematic summation of contributions from phase error of approximately 18° [3]. jitter, trace skew, and network delays guarantees ≥ 90% Any deviation beyond these boundaries immediately coherent gain and the specified dynamic range. This impacts system performance. With differing phases, the article will be helpful to engineers developing phased elements sum non-constructively, energy leaks from the antenna arrays, distributed radar, and interferometric main lobe into sidelobes, and sensitivity drops. For systems, as well as researchers in precise frequency– example, a calculation for an X-band radar with 5-bit time distribution. phase shifters showed that a combination of 3° RMS Keywords: multi-detector phased system; phase and 0.5 dB amplitude ripple yields only – 0.15 dB synchronization; temporal alignment; phase coherence; of gain loss. In contrast, larger drift rapidly broadens the JESD204B/C; zero-delay PLL; microwave exchange; beam and raises sidelobe levels [5]. If node frequencies Kalman-consensus. diverge beyond the discipline of the rubidium standard, Introduction the pattern shifts toward pseudo-random dephasing and, in the extreme, interferometric information is lost. A multi-detector phased system is an ensemble of A temporal desynchronization of hundreds of spatially separated transmit–receive cells in which the picoseconds causes a wideband LFM probe to lose up to resultant wavefront is formed by coherent summation one-quarter of its overlap, forcing the detector to of signals. For summation to be coherent, each node operate with a degraded signal-to-noise ratio. Thus, the must operate under a standard time base, maintain the strict values outlined above are not mere technical same carrier frequency, and know its phase offset standards: they define the narrow region in which a relative to the others. This triad of controls makes multi-detector phased system remains coherent and synchronization a key architectural element: it delivers its designed dynamic range. transforms a set of independent detectors into a unified electrical aperture capable of steering a narrow beam, MATERIALS AND METHODOLOGY constructing interfero