Dual Resonant Frequencies Research Articles

Experimental studies of a miniaturized CPW-fed slot antenna with the dual-frequency operation

Several practical techniques have been employed to modify the operating frequency, enhance the bandwidth and miniaturize the antenna size for a small coplanar waveguide (CPW)-fed slot antenna at 2.4 and 5.2 GHz, the industrial-scientific-medical (ISM) bands. These techniques include: utilizing an E-like feeding structure instead of the conventional T-shaped one; adding a matching stub at the slot edge; adding four floating patches on the bottom plane of the substrate. In experiments, the -10 dB bandwidths achieved were 220 and 600 MHz at 2.4 and 5.2 GHz, respectively. The proposed CPW-fed slot antenna not only creates the dual resonant frequency bands, but the antenna size is also reduced to approximately 60% of the traditional slot antenna. The E- and H-plane radiation patterns of the proposed CPW-fed slot antenna were measured at 2.45 and 5.2 GHz.

Dual-frequency dual-polarized slot-coupled compact microstrip antenna for communication systems

A new design of a dual-frequency dual-polarized square microstrip antenna fed along the diagonal, embedded with a square slot having three extended stubs for frequency tuning, is introduced. The proposed antenna was fabricated using a standard photolithographic method and the antenna was tested using the HP 8510C Vector Network Analyser. The antenna is capable of generating dual resonant frequencies with mutually perpendicular polarizations and broad radiation pattern characteristics. Such dual-frequency designs find wide applications in personal mobile handsets combining GSM and CDS 1800 modes, and applications in which different frequencies are used for emission and reception such as personal satellite communications and cellular network systems.

Dual-frequency aperture-coupled square patch antenna with double notches

A novel design method for an aperture-coupled microstrip patch antenna with a single feeding structure is proposed for dual resonance frequencies with mutually perpendicular polarizations. A new type of square patch with double notches is used as a radiator, and the crossed slot and bended microstrip feeder are adopted for the dual polarizations in the aperture-coupled structure. The characteristics of this antenna were experimentally investigated for generalizing the dual-frequency behavior. A Ku-band Tx/Rx 2×2 subarray antenna was designed and manufactured to examine the applicability as a ground terminal antenna for satellite communications. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 24: 370–374, 2000.

Dual-frequency aperture-coupled square patch antenna with double notches

A novel design method for an aperture-coupled microstrip patch antenna with a single feeding structure is proposed for dual resonance frequencies with mutually perpendicular polarizations. A new type of square patch with double notches is used as a radiator, and the crossed slot and bended microstrip feeder are adopted for the dual polarizations in the aperture-coupled structure. The characteristics of this antenna were experimentally investigated for generalizing the dual-frequency behavior. A Ku-band Tx/Rx 2×2 subarray antenna was designed and manufactured to examine the applicability as a ground terminal antenna for satellite communications. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 24: 370–374, 2000.

Dual band folded monopole/loop antenna for terrestrial communication system

With the introduction of DCS1800 to meet the demands for a wider frequency spectrum for mobile communication systems, novel antenna structures capable of generating dual resonance are in demand. An antenna structure based on the geometry of a bent folded monopole antenna capable of dual resonance frequencies operation is discussed. This antenna is able to cover the GSM/DCS 1800 communication system bands.

Application of a GTO Thyristor to a Dual Resonant Frequency Circuit for the Magnet of a Rapid-Cycling Synchrotron

The first application of a gate-turn-off thyristor to a dual resonant frequency circuit for exciting a rapid-cycling synchrotron magnet has been proposed. For the achievement of this proposal, a small-size model circuit has been constructed and tested. This article describes the experimental results, and some remarks are pointed out.