Shaowei Liao

Differentially Fed Planar Aperture Antenna With High Gain and Wide Bandwidth for Millimeter-Wave Application

This paper presents a novel planar aperture antenna with differential feeding. Compared with conventional high-gain aperture antennas, such as horn and reflector antennas, it maintains a high gain and wide bandwidth, but has a much lower profile with only one quarter-wavelength height. Since the height (λg/4) at millimeter-wave (mmWave) band is as low as the most of the commercially available laminates, planar aperture antennas with high gain and wide bandwidth can be realized at mmWave band using the proposed structure. A prototype working at 60 GHz band was designed and fabricated on a single layer laminate using standard printed circuit board (PCB) technology. A differential feeding network based on E-plane tee was also designed to feed the prototype for the measurement purposes. Experiment results show that the prototype achieves a -15-dB impedance bandwidth from 56.2 to 69.7 GHz (21.5%). The peak gain at broadside is 15.3 dBi at 60 GHz. The 3-dB gain bandwidth is from 54.0 to 67.5 GHz (22.2%). Within the operating bandwidth, the radiation pattern is stable with a low cross-polarization level below -24 dB, and is symmetrical about both the E- and H-planes.

High Gain and Low Cost Differentially Fed Circularly Polarized Planar Aperture Antenna for Broadband Millimeter-Wave Applications

This paper presents a novel circularly polarized (CP) planar aperture antenna for cost-sensitive millimeter-wave, particularly fifth generation (5G), applications. The proposed antenna, which is a differential one, has high gain and wide bandwidth and can be built on a single-layer laminate using standard printed-circuit board (PCB) technology. This makes the antenna both low cost and easy to integrate with common differential circuits. The antenna consists of an opening cavity formed by metalized vias, which encloses a set of loop-like strips that are fed differentially. The strips carry traveling wave current which together with the apertures E-fields distribution give rise to CP radiation. The aperture size of the antenna can be extended for higher gain by adopting a dual- or quadruple-loop-like strips configuration enclosed by a larger opening cavity. The fabricated quadruple-loop-like strips-based antenna prototype designed to operate at 60-GHz band could achieve 3-dB axial ratio (AR) bandwidth of 16.7% (56-66.2 GHz) within its -10-dB impedance bandwidth and stable right-handed CP (RHCP) gain throughout the operating bandwidth with a peak of 14.6 dBi.

A Substrate Integrated Slot Antenna Array Using Simplified Feeding Network Based on Higher Order Cavity Modes

This paper proposes a novel substrate integrated waveguide (SIW) higher order mode cavity fed 2 × 2 -element slot array. The higher order mode cavity feeds all of the slot elements simultaneously, and the resonant mode is excited only by a slot aperture, which helps simplify the feeding network. To enhance the bandwidth, the array is designed as an asymmetric structure with different slot sizes and locations. In this way, new resonances are introduced and thus broaden the bandwidth. Furthermore, the proposed 2 × 2 -element slot array is used as subarray to implement a differentially fed 4 × 4 -element array. The measured results demonstrate that this simple structure antenna array features wideband, high radiation efficiency, good aperture efficiency, and broadside radiation.

Circularly Polarized Planar Aperture Antenna for Millimeter-Wave Applications

This paper presents a novel differentially driven planar aperture antenna with circularly polarized (CP) radiation. The proposed antenna is simple in structure yet can achieve high gain and wide bandwidth, and is constructed using only a single layer laminate via standard printed-circuit-board (PCB) technology. Circular polarization is realized by a rotationally symmetric windmill-shaped patch-aperture formation with travelling wave distribution. The physical aperture of the antenna is constituted by an opening cavity structure formed by metalized vias, which offers high-gain unidirectional radiation pattern. Measurement results of a prototype operating at 60 GHz band show a 3-dB axial ratio (AR) bandwidth of 17.9% (56.5-67.5 GHz), which is within its -10-dB impedance bandwidth. Meanwhile, the left-handed CP (LHCP) gain is stable throughout the operating bandwidth with a peak gain of 13.4 dBi. The proposed antenna is a promising candidate for various consumer level millimeter-wave (mmWave) band applications due to its merits of wideband, high gain, simple structure, low cost, and easy integration with differential circuits.

Dual Polarized Planar Aperture Antenna on LTCC for 60-GHz Antenna-in-Package Applications

This paper presents a novel dual polarized planar aperture antenna using the low-temperature cofired ceramics technology to realize a novel antenna-in-package for a 60-GHz CMOS differential transceiver chip. Planar aperture antenna technology ensures high gain and wide bandwidth. Differential feeding is adopted to be compatible with the chip. Dual polarization makes the antenna function as a pair of single polarized antennas but occupies much less area. The antenna is ±45° dual polarized, and each polarization acts as either a transmitting (TX) or receiving (RX) antenna. This improves the signal-to-noise ratio of the wireless channel in a point-to-point communication, because the TX/RX polarization of one antenna is naturally copolarized with the RX/TX polarization of the other antenna. A prototype of the proposed antenna is designed, fabricated, and measured, whose size is 12 mm × 12 mm × 1.128 mm (2.4λ0 × 2.4λ0 × 0.226λ0). The measurement shows that the -10 dB impedance bandwidth covers the entire 60 GHz unlicensed band (57-64 GHz) for both polarizations. Within the bandwidth, the isolation between the ports of the two polarizations is better than 26 dB, and the gain is higher than 10 dBi with a peak of around 12 dBi for both polarizations.

Ka-Band Omnidirectional High Gain Stacked Dual Bicone Antenna

This communication presents a new omnidirectional antenna based on biconical antenna element to realize high gain and high omnidirectivity at Ka-band. Two biconical antenna elements are stacked and fed differentially by a specially designed differential feeding network embedded inside the antenna. Measurement shows that the -10-dB impedance bandwidth of the antenna is 14.2% (26.2-30.2 GHz), within which the antenna can achieve a high gain of around 12.5 dBi corresponding to a sharp 3-dB beamwidth of about 5° in the elevation plane. The ripple of the omnidirectional radiation pattern in the azimuth plane is smaller than ±0.5 dBi.

Compact UHF Three-Element Sequential Rotation Array Antenna for Satcom Applications

This paper proposes a miniaturized UHF antenna with three sequentially rotated elements operating at 433 MHz for Satcom applications. Like most of its former counterparts, the antenna consists of a main body with three radiation elements driven by a feeding network. To evaluate the matching characteristics of the main body, a united reflection coefficient for the three elements, taking into consideration the coupling between them, is derived. The main body is formed by three sequentially rotationally arranged bent planar inverted-F antenna elements, which helps dramatically reduce the size of the antenna. To drive the main body, a new compact feeding network based on spiral-shaped Wilkinson power divider is also developed, achieving three-way power splitting and 120° phase shifting. It has the merits of compact planar structure, equal power splitting, and high isolation between output ports. In this way, a sequential rotation array antenna with compact size (Ø

A wideband microstrip dual balun structure

0.216\lambda _{0}

A novel unidirectional circularly polarized antenna

), low cost, easy fabrication, and good performance is realized. A prototype is fabricated and measured, and the results prove the good performance of the proposed design.

60 GHz Dual-Circularly Polarized Planar Aperture Antenna and Array

A new wideband microstrip dual balun structure is presented. The proposed wideband dual balun is based on the second higher order mode microstrip line and the 180° out-of-phase and equal magnitude of the balun outputs can be achieved inherently. The experimental results show that the balun has simple structure, wideband impedance matching and good amplitude/phase balance performance.