Title :
A tunable second-resonance cross-slot antenna
Author :
Forman, M.A. ; Popovic, Z.B.
Author_Institution :
Dept. of Electr. Eng., Colorado Univ., Boulder, CO, USA
Abstract :
Second-resonance slot antennas, due to their ability to transmit and receive on both sides of a microstrip ground plane, are often employed in planar active antenna arrays. For example, in an amplifier array, the input and output of an amplifier circuit are connected to orthogonally polarized antennas. The purpose of using orthogonal polarizations is to ensure amplifier stability. We present a 7 GHz cross-slot antenna designed to be used in a mixer/phase detector active antenna. By incorporating a varactor diode into the microstrip feed line, the cross-slot resonance can be electronically tuned over a 10% bandwidth. By mechanically varying the feed line (tuning stub) length, a 45% 2:1 VSWR bandwidth is possible.
Keywords :
active antenna arrays; antenna feeds; circuit stability; detector circuits; electromagnetic wave polarisation; microstrip antenna arrays; microwave amplifiers; microwave antenna arrays; microwave detectors; microwave mixers; slot antenna arrays; tuning; varactors; 7 GHz; SHF; VSWR; amplifier array; amplifier circuit; amplifier stability; bandwidth; cross-slot resonance; electronically tuned resonance; feed line length; input; microstrip feed line; microstrip ground plane; mixer/phase detector active antenna; orthogonally polarized antennas; output; passive antenna; planar active antenna arrays; receiving antenna; transmitting antenna; tunable second-resonance cross-slot antenna; tuning stub length; varactor diode; Antenna arrays; Bandwidth; Feeds; Microstrip antenna arrays; Microstrip antennas; Polarization; Receiving antennas; Slot antennas; Transmitting antennas; Tunable circuits and devices;
Conference_Titel :
Antennas and Propagation Society International Symposium, 1997. IEEE., 1997 Digest
Conference_Location :
Montreal, Quebec, Canada
Print_ISBN :
0-7803-4178-3
DOI :
10.1109/APS.1997.630066
