Abstract: Disclosed is an optical frequency controlling device for ultra-dense wavelength-division-multiplexed optical channels in which center frequencies of optical channels are aligned.

Abstract: The present invention discloses to an SMA connector, a preferable embodiment of which comprises a body acting as ground, a central conductor existing in the inner part of the ground, an insulator with a predetermined dielectric constant existing between the body and the central conductor, a first step transition part formed in the body, a taper formed in the central conductor in order to improve RF characteristics and to fix the central conductor and the insulator, and a second step transition part formed in the central conductor corresponding to the first step transition part to improve RF characteristics.

Abstract: This invention relates to a microstrip array antenna, especially a broad-band dual-polarized microstrip array antenna having parallel feeding structure whose consist of two parts power supplying layers each of which generates its own polarization respectively. And the broad-band dual-polarized microstrip array antenna according to the present invention arranges transmission paths for two separate linear polarization on a different layer each other in order to minimize an interference effect and a proximity feeding method and an aperture coupled method are used in order to get two separate polarization.