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arXiv · 2003.12623

Radiation Efficiency Limits in Direct Antenna Modulation Transmitters

Kurt Schab
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Abstract

Relative bounds on radiation efficiency are established for time-modulated antenna systems where radiation is generated by broadband conduction currents impressed using idealized non-radiating time-varying subsystems, such as those found in direct antenna modulation (DAM) transmitters. Analytical and numerical examples demonstrate that the condition of quasi-resonance, common in nearly all practical direct antenna modulation transmitters, imposes severe restrictions on the otherwise unbounded gains in effective efficiency theoretically achievable by this class of time-modulated transmitters.

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Kurt Schab. 2020-03-27. Radiation Efficiency Limits in Direct Antenna Modulation Transmitters. https://doi.org/10.1109/lawp.2020.3005412

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