A varactor-tuned dual-band slot antenna

A new technique for designing dual-band reconfigurable slot antennas is introduced. The technique is based on loading a slot antenna with a lumped capacitor (or varactor) at a certain location along the slot. Given a fixed capacitor location along the slot, decreasing the capacitance results in increasing the first and second resonant frequencies of the slot antenna. However, the changes in the resonant frequencies are significantly different for the first and second resonances and, hence, a dual-band antenna with considerable frequency ratio tuning range can be obtained. Based on this technique, an electronically tunable dual-band antenna with a frequency ratio in the range of 1.2-1.65 is designed and fabricated using a single varactor with a capacitance range of 0.5-2.2 pF. The antenna has similar radiation patterns with low cross-polarization levels at both bands and across the entire tunable frequency range.

[1]  Zhongxiang Shen,et al.  Effect of a finite ground plane on microstrip-fed cavity-backed slot antennas , 2005, IEEE Transactions on Antennas and Propagation.

[2]  N. Behdad,et al.  A wide-band slot antenna design employing a fictitious short circuit concept , 2005, IEEE Transactions on Antennas and Propagation.

[3]  N. Behdad,et al.  Bandwidth enhancement and further size reduction of a class of miniaturized slot antennas , 2004, IEEE Transactions on Antennas and Propagation.

[4]  D. Chatterjee,et al.  Effect of ground plane size on the performance of a class of microstrip antennas on microwave substrates , 2004, IEEE Antennas and Propagation Society Symposium, 2004..

[5]  Jin-Sen Chen.  Triple-frequency annular-ring slot antennas fed by CPW and microstrip line , 2003, IEEE Antennas and Propagation Society International Symposium. Digest. Held in conjunction with: USNC/CNC/URSI North American Radio Sci. Meeting (Cat. No.03CH37450).

[6]  Kamal Sarabandi,et al.  A novel approach for miniaturization of slot antennas , 2003 .

[7]  Carlos Camacho-Peñalosa,et al.  Dual-band, single CPW port, planar-slot antenna , 2003 .

[8]  Chien-Jen Wang,et al.  Experimental studies of a miniaturized CPW-fed slot antenna with the dual-frequency operation , 2003, IEEE Antennas and Wireless Propagation Letters.

[9]  Kin‐Lu Wong.  Compact and Broadband Microstrip Antennas , 2002 .

[10]  K. Sarabandi,et al.  Design of an efficient miniaturized UHF planar antenna , 2001, IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229).

[11]  R. Garg,et al.  Microstrip Antenna Design Handbook , 2000 .

[12]  Isabelle Huynen,et al.  Effect of surface wave diffraction on radiation pattern of slot antenna etched in finite ground plane , 2000 .

[13]  Kin-Lu Wong,et al.  A DUAL-FREQUENCY EQUILATERAL-TRIANGULAR MICROSTRIP ANTENNA WITH A PAIR OF NARROW SLOTS , 1999 .

[14]  Kin-Lu Wong,et al.  Inset-microstrip-line-fed dual-frequency circular microstrip antenna and its application to a two-element dual-frequency microstrip array , 1999 .

[15]  Wee Sang Park,et al.  Network modeling of an inclined and off-center microstrip-fed slot antenna , 1998 .

[16]  Kazuhiro Hirasawa,et al.  Slot antenna with parasitic element for dual band operation , 1997 .

[17]  Stefano Maci,et al.  Dual-band slot-loaded patch antenna , 1995 .

[18]  A. Giarola,et al.  Effect of a finite ground plane thickness on the radiation pattern of an aperture antenna , 1988, 1988 IEEE AP-S. International Symposium, Antennas and Propagation.

[19]  K. Joshi,et al.  Impedance of a radiating slot in the ground plane of a microstripline , 1982 .

[20]  K. Gupta,et al.  Microstrip Lines and Slotlines , 1979 .

[21]  L. J. Chu.  Physical Limitations of Omni‐Directional Antennas , 1948 .