Abstract: A method (300) and a communication network (110) for rewarding subscribers based on usage of air time are described herein. The communication network (110) may determine usage of air time for communication services by a subscriber (A1). Based on the usage of air time, the communication network (110) may assign a number of points to the subscriber (A1). Accordingly, the communication network (110) may store the number of points assigned to the subscriber in a point account (222) associated with the subscriber (A1). The points accrued in the point account (222) may be redeemed by the subscriber (A1) for one of a service and a product.

Abstract: An antenna assembly for a portable radio apparatus, such as a cellular phone, having a housing with a signal line therein includes a helical antenna extending from the housing and having first and second helical portions which are electrically separated from each other and a rod antenna movable relative to the helical antenna between a retracted position, in which the rod antenna is removed from within the helical antenna into the interior of the housing, and an extended position, in which the rod antenna extends through the helical antenna to the exterior of the housing.

Abstract: An antenna assembly has a first helical antenna and a second rod antenna extending through inside said first antenna in the axis direction. When the antenna is retracted, the upper end of a conductive portion of the second antenna passes through the first antenna to be positioned below the lower end of the first antenna, and when the antenna is extended, the lower end portion of the conductive portion of the second antenna is electrically connected to the upper end portion of the first antenna. Therefore, the length of the second antenna can be reduced as compared with a length defined based on wavelengths of transmitted signals. Consequently, an antenna assembly which requires a smaller housing space can be obtained.

Abstract: A portable radio receiver for diversity reception in which electrical waves having different planes of polarization are received and synthesized at the receiving side using plural antennas. The radio receiver includes a metal casing, an external antenna mounted on one of the surfaces of the metal casing, and a single-side shorted microstrip antenna mounted on a surface of the metal casing so that its shorted surface is at right angles to the main polarization of the external antenna. In this manner, stable directivity and polarization diversity may be achieved in which the main polarization of the external antenna differs from that of the internal antenna and radiation patters are also different between the external antenna and the internal antenna.

Abstract: A planar antenna comprised of a ground conductor, a dielectric layer laminated on the ground conductor, and a rectangular radiation element laminated on the dielectric layer on its surface opposing to the ground conductor, wherein a rectangular opening is concentrically formed through the radiation element so as to provide a ring radiation element and a feed point is disposed near a center of one side of the opening.

Abstract: A matching device for an antenna in which is interposed between an antenna of narrow frequency band and a feeding line so as to match the antenna and the feeding line over a wide band, includes a high impedance line of a first predetermined length provided at the antenna side and a low impedance line of a second predetermined length provided at the feeding line side that are connected in series, whereby the matching device can be made small in size and simple in construction.

Abstract: In the microstrip antenna apparatus according to the present invetnion, a circular radiation element is provided on a grounded conductive planar element through a dielectric layer having a small dielectric loss, and this radiation element resonates in the TM.sub.01 mode. A feed point is located at substantially the center of the circular radiation element, and an impedance matching device is interposed between the feed point and a coaxial connector. The inside conductor of the impedance matching device is connected to the feed point to supply energy to the radiation element, and an outside conductor is connected to substantially the center of the conductive planar element so as to be grounded. Further, this antenna is provided on the microstrip antenna at its topmost portion in which a plurality of conductive planar elements are stacked thereby forming the microstrip antenna which is applicable to a plurality of frequencies.

Abstract: Disclosed herein is a transmission system for determining a position of a mobile station by using communication satellites. The determination of the position of the mobile station is effected by one-line signal transmission from the mobile station through one satellite to a fixed station and by two-line signal transmission from the fixed station through two satellites to the mobile station. Thus, the construction of the transmission system can be made simple such that a transmitter for the one-line signal transmission needs to be mounted on the mobile station.