초록 ▼

The present invention features a dual-band meander line loaded antenna (MLA) that operates in a loop mode for a first frequency band and utilizes capacitive tuning to adjust the monopole resonant frequency for a second frequency band. In one embodiment orthogonal MLA elements are equipped with one o

The present invention features a dual-band meander line loaded antenna (MLA) that operates in a loop mode for a first frequency band and utilizes capacitive tuning to adjust the monopole resonant frequency for a second frequency band. In one embodiment orthogonal MLA elements are equipped with one or more capacitive flaps to lower the monopole resonant frequency of the structure. By offset-tuning the MLA elements and properly feeding RF signals, the inventive antenna exhibits vertically polarized operation at a first operating frequency and circular polarization at a second operating frequency. A typical use for the inventive antenna is for a dual-purpose cellular phone and GPS antenna. In cellular phone mode, the antenna operates at approximately 845 MHz with vertical polarization while simultaneously operating with circular polarization as at 1.5 GHz for GPS services.

대표청구항 ▼

1. A dual-band antenna for simultaneous operation in a first frequency band and a second frequency band, comprising:a) a ground plane; b) a first meander line loaded antenna element tuned to a first loop mode frequency and having a first monopole resonant frequency, said first antenna element being

1. A dual-band antenna for simultaneous operation in a first frequency band and a second frequency band, comprising:a) a ground plane; b) a first meander line loaded antenna element tuned to a first loop mode frequency and having a first monopole resonant frequency, said first antenna element being disposed upon said ground plane, wherein said first meander line loaded element comprises a first pair of vertical sides extending approximately perpendicularly from said ground plane and a first horizontal section juxtaposed between said vertical sides, wherein there are gaps between said first horizontal section and said vertical sides with a first meander line mounted at said gaps; c) a second meander line loaded antenna element tuned to a second loop mode frequency, said second antenna element having a second monopole resonant frequency, said second antenna element being disposed upon said ground plane, wherein said second meander line loaded element comprises a second pair of vertical sides extending approximately perpendicularly from said ground plane and a second horizontal section juxtaposed between said vertical sides, wherein there are gaps between said second horizontal section and said vertical sides with a second meander line mounted at said gaps; d) a means for capacitive tuning said first monopole resonant frequency of said first antenna element to a first monopole frequency; and e) a means for capacitive tuning said second monopole resonant frequency of said second antenna element to a second monopole frequency.