Abstract: A method and apparatus for transmitting broadcast information in a multi-carrier communication system. The Sync Channel of the multi-carrier system is transmitted a 1.25 MHz channel bandwidth (i.e., over a single carrier), and to specify the preferred channels for the Sync Channel transmission instead of the preferred channels for the entire multi-carrier system. The Sync Channel Message will carry additional information indicating the center frequency of a multi-carrier system within a reserved set of frequency bands and indicating the frequency of a single carrier system in the reserved set of frequency bands. Considering the A block of the PCS band again, the preferred channels for Sync Channel transmission can be selected as channels 75, 150 and 225. This selection ensures that one of the preferred channels will always be used by any multi-carrier system regardless of the location of its center channel.
Abstract: A compact, low cost antenna communicates with low and medium earth orbit satellites. The antenna includes a plurality of micro-strip elements arranged about an axis and positioned to illuminate upper elevation angles. The micro-strip elements are perpendicular to each other and are oriented toward the horizon at 90 degree increments. Furthermore, the micro-strip elements are tilted at a 50 degree angle. A quadrifilar helix is positioned at the center of the micro-strip elements and positioned to illuminate lower elevation angles. The micro-strip elements generate an omni-directional field pattern in the azimuth plane. The quadrifilar helix generates a high-gain, narrow beam-width field pattern that is also omni-directional in the azimuth plane. The antenna provides improved immunity to specular ground reflections by limiting reception of signals below a threshold elevation angle.
Type:
Grant
Filed:
September 30, 1998
Date of Patent:
April 11, 2000
Assignee:
QUALCOMM Incorporated
Inventors:
Mohammad A. Tassoudji, Ernest T. Ozaki, William R. Panton