Author :
Nascimento, D.C. ; Bianchi, I. ; Schildberg, R. ; da S.Lacava, J.C.
Abstract :
The mobile personal communications are the last generation of satellite communication. Several operators like Globalstar, among others, offer services of global cover. This system provides voice, facsimile, paging, and data transmission to subscribers using LEO (Low Earth Orbit) satellites, in a well-known Walter delta type constellation. Helical structures can be used as antennas on mobile terminals, particularly on cars or trucks, but they tend to be bulky. On the other hand, microstrip antennas are widely used in mobile communication systems, radar systems, and aerospace applications because of their low weight, low profile, and ease manufacturing. For instance, a dual-band patch antenna printed on 3.2 mm thick FR4 material and designed to satisfy both the frequency ranges of the Iridium and Globalstar systems is reported. However, the antenna radiation efficiency which is certainly low is not mentioned. Moreover, its input impedance is overall inductive due to the probe impedance. In this paper, two truncated corner patches printed on CuClad 250 GX microwave laminate, designed to operate as receiving (Rx) and transmitting (Tx) antennas on mobile terminals of Globalstar system, are presented. The design includes a new procedure to compensate the reactive inductance of the antenna input impedance.
Keywords :
antenna feeds; microstrip antennas; microwave materials; mobile satellite communication; probes; receiving antennas; satellite antennas; transmitting antennas; CuClad 250 GX microwave laminate; Globalstar system; LEO satellites; Walter delta type constellation; mobile personal communications; mobile terminals; probe-fed truncated corner microstrip antenna design; receiving antennas; satellite communication; transmitting antennas; Aerospace materials; Data communication; Facsimile; Helical antennas; Impedance; Low earth orbit satellites; Microstrip antennas; Mobile antennas; Radar antennas; Satellite communication;
