Chung-Yi Hsu

A compact printed UWB MIMO antenna with a 5.8 GHz band notch

A compact printed UWB MIMO antenna with a 5.8 GHz band-notch is presented. The two antennas are located on the two opposite sides of a Printed-Circuits-Board (PCB), separated by a spacing of 13.2 mm and a small isolated element, which provides a good isolation. The antenna structure adopts coupled and parasitic modes to form multi-modal resonance that results in the desired ultra-wideband operation. There is a parasitic slit embedded on the main radiator and an isolated element employed between the two antennas. An excellent desired band-notched UWB characteristic was obtained by care design of the parasitic slit. The overall size of the proposed antenna is mere 40.2×54×0.8 mm; the radiation patterns of the two antennas cover the complementary space of 180o; the antenna yields peak gains varied from 5 to 8 dBi, and antenna radiation efficiency exceeding about 70~90 % over the operation band. The antenna port Envelope Correlation Coefficient (ECC) was less than about 0.07. Moreover, the antenna is easy to fabricate and suitable for any wireless modules applications at the UWB band.

Design of a printed 60 GHz Quasi-Yagi antenna for millimeter wave wireless communication applications

A low-cost, printed 60 GHz millimeter-wave Quasi-Yagi antenna is demonstrated. It is fed by balanced outputs of a balun connected to a micro-strip line input. The proposed antenna shows a measured impedance matched bandwidth of BW = 8.9 GHz ranging from 56.3 to 65.2 GHz using the return loss less than -10 dB as the criterion. It has 60o half power beam width (HPBW) in the E-plane, and 75o HPBW in the H-plane at the center frequency (60 GHz). It exhibited about 11.8 dB front-to-back (F/B) ratio and excellent 8.9 dB absolute peak gain. Measured results are in good agreement with electromagnetic simulations. It is expected to be used in 5Gs indoor wireless communications.

Detection of vital signs for multiple subjects by using self-injection-locked radar and mutually injection-locked beam scanning array

This study combines self-injection-locked (SIL) radar and ILO-based phased array to conduct non-contact vital sign detection on multiple users. For this purpose, multiple injection-locked oscillators (ILOs) are mutual injection locked to each other at a common frequency. By adjusting the tuning voltages of ILOs, the phase shift among ILOs can be controlled, and therefore the beam scanning of the array can be achieved. Moreover, the signals reflected from the chest of the subjects are injected into the ILOs to enter an SIL state for radar operation. In the experiment, the prototype operating in the 2.4-GHz ISM band is utilized to detect the vital signs of three subjects within two meters at different azimuth angles relative to the array.

A broadband probe-fed 4×4 array antenna

A broadband probe-fed array antenna for Ku-band application is proposed. The configuration of the antenna is adopted as 4×4 array, and it is used the parallel feeding network to set up the current magnitude and phase. The operating band is covering 10.3∼12.7 GHz which bandwidth is 2.3 GHz. The array is utilized an intermediate pillars to connect the array and feeding network, which is hoped to reduce the surface wave loss and increased operating bandwidth. The operating bandwidth of the array is about 25 percent; the radiating gain of the antenna system is about 16.3dB. The gain flatness within operating band is about 0.25 dB, the aperture efficiency is about 38%. Moreover, we use of simulation software to explore different substrates loss for the gain change, and find out the lower cost to be applied to the substrate on the Ku-band array applications.

A high port isolation MIMO antenna system for 2–6 GHz wide-band AP applications

A novel wide-band multiple-input multiple-output (MIMO) antenna system with high port isolation is proposed. The antenna system consists of three equally spaced antennas mounted on a hollowed triangle ground. The antenna system was designed to operate at frequency bands between 2 and 6 GHz. Each antenna mainly comprises of a shorted, inverted wide L (shorted iWL, a unique feeding design), sitting on a vertical ground attached to the horizontal plane of triangular shape. From simulation and experimental results, the proposed MIMO system exhibited superb characteristics at 2.4, 3.5 and 5 GHz bands, with significant isolation performance due to the design of the practical and novel ground structure.