Title :
Cavity induced polarisation switching in a slot-loop active antenna
Author :
Chen, Q. ; Zheng, M. ; Fusco, V.F. ; Hall, P.S.
Author_Institution :
Dept. of Electr. & Electron. Eng., Queen´s Univ., Belfast, UK
Abstract :
The new features of a cavity backed active slot-loop antenna are discussed in this paper. By using a high Q cavity, 35 dBc phase noise level reduction at 200 kHz from the carrier has been achieved. Once in resonance, the established TE/sub 110/ cavity fields rotate the principle E-plane of the slot-loop antenna through 90/spl deg/. This results in an exchange of E- and H-plane locations in the radiation pattern together with reduced cross-polarisation levels. Thus the presence of the cavity tuned into and out of resonance allows the antenna to have its polarisation properties orthogonally switched.
Keywords :
Q-factor; antenna radiation patterns; cavity resonators; electromagnetic wave polarisation; interference suppression; loop antennas; phase noise; resonance; slot antennas; switching; 5.5 GHz; TE/sub 110/ cavity fields; cavity backed active antenna; cavity induced polarisation switching; cross-polarisation levels reduction; high Q cavity; orthogonal switching; phase noise level reduction; polarisation properties; principle E-plane rotation; radiation pattern; resonance; slot-loop active antenna; Antenna radiation patterns; Dipole antennas; Frequency; Microstrip antennas; Phase noise; Polarization; Q factor; Resonance; Slot antennas; Slotline;
Conference_Titel :
Microwave Symposium Digest, 1998 IEEE MTT-S International
Conference_Location :
Baltimore, MD, USA
Print_ISBN :
0-7803-4471-5
DOI :
10.1109/MWSYM.1998.700865
