摘要 |
There is disclosed a radio-antenna module formed on a daughterboard comprising a substrate, a radio circuit and a monopole antenna. The radio circuit is fed between two points on the monopole antenna having a predetermined relative impedance difference and neither of which points is at zero impedance (ground). The module operates well in a vertical orientation and can discriminate between right and left hand circular polarisation, making it ideal for personal navigation device and other global positioning system applications.
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