Akademik Veri Yönetim Sistemi
AEU - International Journal of Electronics and Communications, cilt.216, 2026 (SCI-Expanded, Scopus)
Time-modulated antenna arrays (TMAs) provide enhanced beamforming flexibility and sidelobe level (SLL) control through temporal excitation. However, conventional formulations assume that antenna elements are inactive during their off states, neglecting mutual coupling effects. This assumption becomes invalid in densely coupled arrays, where switched-off elements can sustain induced currents and act as parasitic radiators. In this work, a coupling-aware analytical framework is developed in which off-state elements are explicitly modeled as parasitic components. The formulation incorporates mutual coupling into the switching process, leading to an effective excitation that is no longer strictly binary and depends on the termination condition of inactive elements (e.g., open-circuit, short-circuit, or matched loads). A comprehensive analysis of switching profiles, harmonic coefficients, and radiation patterns is conducted. Results show that mutual coupling introduces noticeable deviations even at the fundamental component (q=0), affecting SLL, null locations, and beam characteristics. Full-wave simulations based on time-domain averaging confirm that the proposed model accurately captures the coupling-induced current distribution and resulting radiation behavior, whereas the classical formulation leads to significant inaccuracies. These findings highlight the necessity of coupling-aware modeling and demonstrate that mutual coupling can be treated as a design parameter rather than a limiting effect.