Liquid crystal tunable microstrip patch antenna

A microstrip patch antenna operating in the 5 GHz range and tuned by liquid crystal (LC) is described. The simulated tuning range is 8 while the measurements showed a range of 4. Losses in the commercially available LC material at these frequencies give rise to antenna efficiencies ranging from 35 40 at best and falling to around 20 when the LC is in the unbiased state.

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