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Semiconductor electronically beam-steering antennas based on a plasma hologram have been demonstrated as a possiblecosteffective alternative to phased arrays. The paper addresses the design issues critical for antenna operation.Key words: Electron-hole plasma, plasma hologram, beam-steering antennas. 1. INTRODUCTION Plasma is an ensamble of approximately equal numbers of positively and negatively charged free particles. Plasma can affect electromagnetic wave (EW) propagation. An example is the ionosphere, which significantly influences propagation atfrequencies up to 30 MHz. Plasma effects include absorbing, reflecting, and changing the phase velocity of the waves. Plasma reflection by ionosphere is used to increase the distance of radio communications. Plasma mirrors were explored as electronically steerable antennas1'. Plasma was also used as a phase shifting medium in phased array antennas at microwave frequencies3. Plasma/EW effects are adequately described by the classical Drude model (see, for example4). According to the Drudemodel, the presence of plasma changes the complex dielectric constant of the medium |
