Abstract
Radiation quality factor, Q, of an electrically small lossless structure that fits an oblate spheroidal volume for transverse-to-axis polarisation is investigated. Q is evaluated for different size and shape of a spheroid by integrating numerically the stored energy associated with radiation. It is found that Q depends on the distribution of power amongst the various spheroidal modes, and a minimum of Q is achieved by suitable optimisation of the relative amplitudes of these modes. A graphical comparison between the minimum Q of a transversally polarised oblate and an axially polarised prolate spheroid is provided for ellipticities in the range 0.2,…,1. The inverse of the obtained minimum Q serves as an estimate for the bandwidth potential of an arbitrary, linearly polarised lossless radiator inside that volume.
| Original language | English |
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| Pages (from-to) | 201-205 |
| Journal | AEÜ: International Journal of Electronics and Communications |
| Volume | 57 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2003 |
| MoE publication type | A1 Journal article-refereed |