Shengchang Lan

A 77GHz bioradar antenna module design using microstrip arrays

This paper presented the design of a linear polarized antenna module for bioradar sensors using microstrip arrays. This antenna module was designed operating at 77GHz for remote contactless evaluation of human vial signals. This antenna module consisted of a series of vertically aligned linear arrays. Each of the linear array was formed by 10 micro patches connected by quarter-wave impedance transformers which enable to achieve low sidelobes in a simple, compact, and planar structure and good impedance matching. This module had a dimension of 43.79×25.04 mm2, easily integrated with RF circuits. The calculated antenna gains on the H-plane and E-plane are higher than 25.01 dB. The HPBW on the H-plane and E-plane is 12 degree. Moreover, the side lobe level at 76.5GHz for H-plane is -12.5 dB. And for E-plane, the result is -11.5dB. This simple, planar structure offers the advantage of easy manufacturing compared to present lens and alternative technologies in bioradar applications.

Design and investigation of a compact slot antenna with WLAN band rejection for UWB systems

A novel compact printed antenna fed by CPW with WLAN band rejection for UWB applications is proposed in this paper. This symmetrical antenna features three parts: a semicircular stub as the UWB radiator, a pair of modified compact patches which are integrated smoothly as the ground plane with the line-to-arc transition structures, and two U-shaped slots which are embedded on the ground plane to reject WLAN band radiations. This antenna with the miniaturized dimension of 25mm × 25mm × 1.5mm and excellent performance in frequency and time domains characteristics, has a VSWR less than 2 between 3GHz to 16.6GHz, stable H-plane omnidirectional radiation patterns, and constant group delay from 3GHz to 12GHz except the notched bandwidth of 5.05-5.88GHz. Good agreement between the measured and simulated results can be observed.

Novel design of dual-band conical dielectric resonator antenna with circular patch feed

A dual-band conical dielectric resonator antenna with circular patch feed has been presented in this paper. Using conical dielectric resonator, the resonance frequency of monopole can be reduced contributing to antenna miniaturization, and high-order hybrid mode resonance can be achieved for another operating band. The circular patch fed by coaxial line performs the functions of the feeding structure of the conical dielectric resonator and an effective radiation element. Based on the above concept, an antenna for indoor communication applications has been presented. The proposed antenna features -10dB impedance bandwidth of 780MHz and 940MHz in lower and upper bands.

Is it Possible to Detect the Stealth Flying Objects by the

This work evaluates the possibility of using the passive millimeter waves (PMMW) radiometric discriminator for the remote control and the detection of stealth aircrafts.

A time domain RCS measurement system by using an ultra-wide band radar

This paper introduced a method of investigating radar cross sections (RCS) of the target object using an ultra-wide band radar. Unlike the conventional RCS measurement in frequency domain, this time domain RCS measurement adopted a series of ultra-short pulses to acquire the frequency responses of the echoes scattered from the target object under test. Analyzing the effective power of the echoes scattered by the calibrating object and the target object can show the reflectivity properties of different materials and structures over the frequency band from 0.8GHz to 18GHz through only a single measurement. Theoretical calculations and system configurations are presented, analyzed and optimized in this paper. Demonstration experiments of measuring a 35mm sphere and a handicraft airplane are implemented to verify the feasibility of this proposed method. The final results show this time domain RCS measurement by using an ultra-wide band radar is able to provide the reduction in the measurement procedure complexity, anti-disturbance of measuring surroundings and an agreement with the numerical analysis.

About single block with receiver and frequency-meter in Terahertz band at the base of Josephson junction

On the basis of previous theoretical and experimental investigation, here we propose the design of a super wide panoramic receiver-frequency-meter (PRF) based on the Josephson junctions (JJ). This solution is particularly suitable for experimental purposes rearding new generation structures for which radiative power is small and operating frequency is not accurately known. In particular, we present two devices based on the JJ. The first one is the receiver based in self-pump mode regime of JJ and second one is a super wide frequency-meter.

Wide-Range Tuner for Generators in THz Bands

Before experiments can be conducted on new generation structures in the THz band when the level of power is small and especially the frequency are practically unknown correctly ( or it has place some accidental character) it is necessary to have instruments capable of measuring weak signals in a wide-range frequency band. Receiving instruments for the above-described evaluations must be based better by one measuring block and not only in the limits of the intermediate frequency (IF) amplifier band. Best natural “candidate” for this task is Josephson junction (JJ) – it has super wide voltage electronic regulation on frequency by basic ratio 2eV= hω. JJ can be used as the criterion for a single-block super-wide band frequency-meter and as a sensitive element for the tuning the generation structures. Short description presents the realized innovative idea about simple tuner for generators in THz bands.

Josephson generation is good for pixel in the array of passive imaging system

One of the critical technologies is combining both of superconductive and semiconductor technologies on a single substrate, including creating Josephson junction (JJ) near the gate of a semiconductor transistor. The use of JJ in self-pumping mode regime as one of the heterodyne detection methods can provide a new trend for designing modern passive terahertz imaging system. Further development will allow to realize multi-spectrum systems with electronically tunable band. This paper discussed the theoretical analysis on the noise characteristics of the JJ as the pixels in the array of passive imaging system. The analytical result shows that JJ is a possible solution to improve the sensitivity of modern multi-spectrum passive imaging systems.

Josephson junction as the pixel with voltage tuning of frequency in matrix passive imaging system

A Josephson junction (JJ) can be conveniently used in modern passive terahertz imaging system. JJ can be presented and described as the noise heterodyne in pixels based on the receiver consisting of JJ mixer in self-pumping regime connected with intermediate frequency amplifier. This study presents the theoretical basis and calculations of the possible sensitivity in the radiometric regime. Further development of the superconducting and semiconducting technology on the single substrate will allow to realize matrix passive imaging system with electronic tuning of the receiving frequency band.

Some minding about the creation of multi-spectrum passive terahertz imaging system

One of the priority trend in electronics is the design of the imaging system in various spectral band of the electromagnetic waves. Multi-spectrum system is one of the critical technologies. It is principal to direct efforts for the creation multi-spectrum system in single block with simple regulation of the receiving band. First question in this field is to do the receiving pixel with tunable band for the matrix imaging system. Best candidate for this aim is Josephson Junction (JJ). The using of the JJ for this purpose can stay the new trend for the creation modern multi-spectrum passive terahertz imaging system. There proposed some analysis at the base of theoretical and experimental results of the possible noise parameters of the such pixel.