Dielectrically loaded antennas with low proximity effects for 3G applications

Sarantel has been researching into a miniature dielectric-loaded bihelix antenna, which takes control of the resonant near-fields through the use of a high-dielectric core and also a feed topology that isolates the antenna from the application platform. This independence from environment delivers the improvements to many installed performance metrics and also provides important electrical benefits. For example this paper shares evidence that this strategy makes the electrical performance of the antenna predictable across all environments of normal use. Additionally the feed system can provide an attenuation of conducted in-band common-mode noise (arising from sources in the handset) that impairs the sensitivity of the system. A generic problem with small antennas is that they have narrow radiation bandwidths; insufficient to span the bandwidths that are required to meet the needs of the particular wireless service that they serve. At Sarantel we have developed a technology that forms a multi-pole response that is configured to envelop the required 3G bandwidth. The theoretical working function of the antenna is presented alongside measured results to prove the proposed theoretical background. This technology can be applied for antennas in Bluetooth, PCN and other communication bands.