Junfeng Xu

Bandwidth Enhancement for a 60 GHz Substrate Integrated Waveguide Fed Cavity Array Antenna on LTCC

A substrate integrated waveguide fed cavity array antenna using multilayered low temperature co-fired ceramic technology is presented and designed at V-band (60 GHz). The 8 × 8 antenna array is designed with an enhanced bandwidth of 17.1% and a gain up to 22.1 dBi by reconfiguring radiating elements, feeding network, and the transition. The proposed array antenna also features the merits of compact size, stable performance, and high efficiency.

Axial Ratio Bandwidth Enhancement of 60-GHz Substrate Integrated Waveguide-Fed Circularly Polarized LTCC Antenna Array

A substrate integrated waveguide (SIW)-fed circularly polarized (CP) antenna array with a broad bandwidth of axial ratio (AR) is presented for 60-GHz wireless personal area networks (WPAN) applications. The widened AR bandwidth of an antenna element is achieved by positioning a slot-coupled rotated strip above a slot cut onto the broadwall of an SIW. A 4 × 4 antenna array is designed and fabricated using low temperature cofired ceramic (LTCC) technology. A metal-topped via fence is introduced around the strip to reduce the mutual coupling between the elements of the array. The measured results show that the AR bandwidth is more than 7 GHz. A stable boresight gain is greater than 12.5 dBic across the desired bandwidth of 57-64 GHz.

CPW Center-Fed Single-Layer SIW Slot Antenna Array for Automotive Radars

A compact co-planar waveguide (CPW) center-fed substrate-integrated-waveguide (SIW) slot antenna array is proposed to achieve narrow H-plane beamwidth and low sidelobe levels for automotive radars such as across-the-road (ATR) radar. The antenna consists of an array of SIW slot elements, a CPW-SIW transition, and a CPW power divider. A new type of CPW-SIW transition is proposed to minimize the blockage aperture of the slot antenna array for suppressing the sidelobe levels of the array. A parallel center feeding configuration is applied to avoid beam squinting. The antenna prototype printed onto a single-layer Rogers 5880 is with 32 ×4 slot elements and an overall size of 195 mm×40 mm×0.79 mm. Measured results show that the proposed antenna exhibits a gain of > 22.8 dBi, an efficiency of > 67%, a return loss of > 10 dB, a sidelobe level of <;-21 dB, and a fixed boresight beam of <;4.6° in H-planes over 24.05-24.25 GHz, suitable for ATR radar.

270-GHz LTCC-Integrated High Gain Cavity-Backed Fresnel Zone Plate Lens Antenna

A compact cavity-backed Fresnel zone plate (FZP) lens antenna, integrated in low-temperature co-fired ceramic (LTCC) is proposed to achieve high gain at 270 GHz band. The gain is enhanced by using the back cavity formed by a via sidewall and a ground plane. A compact feeding transition is proposed to realize the broadband impedance matching in order to reduce the considerably large reflection at high permittivity substrate-air interface when the antenna is directly fed by an external air-filled waveguide. The measured results show that the proposed cavity-backed FZP lens antenna achieves a boresight gain of 20.8 dBi at 270 GHz and a 3-dB gain bandwidth of 9.1 GHz (266.2–275.3 GHz).

270-GHz LTCC-Integrated Strip-Loaded Linearly Polarized Radial Line Slot Array Antenna

A planar linearly polarized radial line slot array (RLSA) antenna is proposed to achieve a high gain with improved impedance matching and suppressed cross-polarization levels at a 270-GHz band. The proposed antenna is integrated in low-temperature cofired ceramic (LTCC). The impedance matching is enhanced by loading each radiating slot individually with a strip pair and employing an integrated feeding transition to an external standard waveguide in measurement. The cross-polarized radiation level is suppressed at all directions by aligning the orientations of the radiating slots. The antenna prototype exhibits the measured |S11| less than -10 dB over the frequency band of 261.3-282.2 GHz, a maximum boresight gain of 27.6 dBi at 275.2 GHz, and a 3-dB gain bandwidth of 9.8 GHz (271.2-281 GHz).

Substrate-integrated antennas at 60/77/140/270 GHz

The recent research and development of the planar substrate-integrated millimeter-wave/sub-millimeter-wave antenna technologies are reported. The selected planar antenna designs fabricated onto print circuit board (PCB) or low temperature co-fired ceramic (LTCC) substrate operating at 60/77/140/270-GHz bands are addressed.

A broadband circularly polarized antenna

A right-handed circularly polarized antenna is proposed with a broadened bandwidth in terms of axial ratio, impedance matching and gain. The antenna consists of a suspended slotted patch and an L-shaped feeding probe. An antenna prototype with an overall size of 250 mm × 250 mm × 50 mm exhibits a measured mimimum gain of 6.4 dBic, axial ratio less than 3 dB, and reflection coefficient less than -10 dB over the frequency band of 800-960 MHz, which makes the antenna suitable for ultra high frequency (UHF) RFID applications.

Design and measurement of substrate-integrated planar millimeter wave antenna arrays at 60–325 GHz

Antenna development at mmW bands has many unique challenges from design, fabrication to measurement. The designs usually suffer from high losses and difficulty in integrating into circuits. The fabrication is often associated with critical tolerance as one of the toughest issues because of expensive testing setup, critic requirements for reliable connection between antenna under test and feeding system, customized calibration setup and procedures. Using substrate-integration technology, the antennas will be fabricated onto substrate to reduce cost, size, transmission loss, and enhance integration into circuits. This talk will brief the design challenges in mmW antenna design and substrate-integration technology first. After that, recently developed substrate-integrated high-gain antenna arrays for 60-270 GHz applications are exemplified with the introduction of the latest built measurement system up to 325 GHz. Last, the comments on the development of the substrate-integration technology in antenna design at mmW and submmW bands are provided.

Dielectric loading effect on 140-GHz LTCC SIW slot array antenna

This work investigates the effect of dielectric loading on a 140 GHz LTCC SIW slot antenna array. Four types of dielectric loading are designed and discussed. The performance of the antennas with the dielectric loadings is compared in terms of directivity and return loss. An antenna with a simplified dielectric loading configuration with less vias exhibits comparable performance but easier LTCC antenna fabrication and lower cost.

LTCC integrated millimeter-wave antennas (invited talk)

Summary form only given. In this presentation an overview of traffic video detection will be given from the point of view of a manufacturer. Founded in 1992 Traficon is today one of the leading companies in the world for traffic video detection. The history and the current markets of Traficon are shortly presented together with some key reference projects. Next some new market and technology trends are presented and how Traficon responds to these. As a high tech company playing in a highly dynamic technology landscape it is essential to create strategic alliances with research institutes and other companies. This requires the right mind set, the need for formal ways of cooperating, the awareness that product quality is key and last but not least a good nose for market trends. Some of these aspects will be highlighted. Finally it will be explained how Traficon is dealing with this.