Monopole-loaded small loop antennas eliminating a matching circuit

The authors propose the structure of a monopole loaded small loop antenna (MLLA), where the inductive element of the inverted L antenna (ILA) is replaced by a loop antenna. The monopole part is used as the matching element that lets the loop antenna resonate. MLLAs are found to work without additional circuits when antenna length almost matches the length that yields resonance as calculated by the ILA model. The MLLA radiation pattern duplicates that of a combined antenna model consisting of a small monopole antenna and a small loop antenna. When an MLLA-equipped device is carried, its sensitivity is superior to that of devices using either monopole or loop antennas.<>