Naohisa Goto

1-wavelength loop type dielectric chip antennas

We propose a 1-wavelength loop type dielectric chip antenna that meets the demand for antennas with unidirectional radiation patterns for portable communication devices. The structure of the proposed antenna is shown. The radiating element printed loop is on the top of the cube. A feeding strip line is on one of the vertical face of the cube and a shorted plate parallel to the feeding strip line is on the same face. The conductive plane is on the bottom of the cube. By printing all of conductive elements on a ceramic cube this novel antenna is easy to fabricate.

A double-layered self-diplexing antenna using ring patch antenna and its feed circuits

A circularly polarized self-diplexing antenna (SDA) for mobile satellite communications is analyzed from the viewpoint of internal isolation. The mutual coupling between transmitting and receiving of the SDA greatly depends on the output amplitude and phase imbalance of the feed circuits. The feed circuits give an isolation of more than -50 dB for two- and four-feed points of the SDA. Simulation of the output amplitude and phase errors for four-feed circuits shows the theoretical limit of the suppression of the isolation. To obtain an isolation loss of less than -50 dB, it is necessary that the output power imbalance of the feed circuits be less than 0.5 dB of amplitude error and less than 0.5 degrees of phase error.<<ETX>>