Guide Zhu

Bio: Guide Zhu is an academic researcher from University of Electronic Science and Technology of China. The author has contributed to research in topics: Radiometer & W band. The author has an hindex of 3, co-authored 5 publications receiving 16 citations.

A W-band miniature power divider based on E-faced-folded magic-T junction

Abstract: A novel design of W-band power divider using E-faced-folded waveguide magic-T junction to realize the miniaturization is proposed in this paper. A stepped regular triangular prism and the stepped impedance transformer are utilized in order to obtain excellent performance. Besides, the performance of the E-faced-folded magic-T power divider is also improved by using short planes. The measured results show that the insertion loss of the power divider is better than 0.6dB and the return loss is better than 15dB. The measured average E-H isolation is better than 30dB from 92GHz to 100GHz range.

Design of LPF using suspended substrate microstrip lines as high-Z sections for stopband extension

Abstract: This article introduces the use of suspended substrate microstrip lines (SSMLs) as high-Z sections in the design of lowpass filters (LPFs) to extend the stopband. The SSMLs are formed by etching slots on the backside of microstrip lines and placing the substrate on an aluminum base with grooves that cover these slots. The higher characteristic impedance property of SSMLs brings about not only shorter length for high-Z lines but also a larger high-to-low impedance ratio, thus deepening the stopband suppression and shifting the spurious passband away. As a demonstration, a wide stopband LPF combining this structure with hammer-shaped stubs is designed, fabricated, and measured. The 20 dB stopband is obtained from 1.45 to 11.77 GHz. Compared with reported LPFs, this shows the widest fractional bandwidth (FBW) of 156% without sacrificing other performances. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1204–1207, 2016

Millimeter wave high-resolution imaging medium lens antenna design method

Abstract: The invention discloses a millimeter wave high-resolution imaging medium lens antenna design method. The method is a design method combining optical lens design technology and millimeter wave antenna design theory, relating to the technical field of a millimeter wave antenna. By using an optical lens curved surface, the wave aberration and the geometrical aberration of a system are optimized by an optical design method, so that -3dB light spot diameter of feed source antenna units on an object plane is the smallest, and the gain inequality value of each feed source antenna unit is smaller than 1dB. The design method has the characteristics of simpleness and easy use, and the resolution ratio of the millimeter wave lens antenna is innovatively defined. The design method provided can be applied to a millimeter wave imaging system.

Multi-channel radiometer system front end and control method of consistency thereof

Abstract: The invention discloses a multi-channel radiometer system front end and a control method of consistency thereof. The multi-channel radiometer system front end consists of a plurality of single-channel radiometer front ends in an array way, wherein each single-channel radiometer front end comprises a radio frequency amplification and wave detection module, a video amplification module, an integral regulation module and a difference amplification and reference potential regulation module; the radio frequency amplification and wave detection module, the video amplification module, the integral regulation module and the difference amplification and reference potential regulation module are connected in turn; the output end of the difference amplification and reference potential regulation module outputs a voltage signal Vout. According to the multi-channel radiometer system front end, the problem of inconsistent multi-channel radiometer system front ends can be effectively solved, an external standard calibration source and an additional circuit structure are not required, and the multi-channel radiometer system front end has the advantages of small volume, high integration degree and simple technology.

W-band dual-channel direct detection radiometer front-end for array

Abstract: To ensure real-time functioning of radiometer system, the radiometer modules need to be arranged in array. In this paper, a highly integrated and miniaturized W-band dual-channel radiometer front-end with regular structure, good electromagnetic compatibility and temperature sensitivity is realized. For the integrated dual channel radiometer module, a series of debugging tests are implemented to improve the temperature drift and temperature sensitivity, and also to ensure the consistence of gain. When the transient time of the module is less than 1ms, the measured results show that the whole band has an apparent frequency response and its two channel temperature sensitivity can achieve 0.41K and 0.43K, respectively, which indicate that the dual channel module has good results. Simultaneously, the temperature recognition rate of the brightness temperature is 6.3mv/K and 6.18mv/K. The module meets the requirement of the radiometer system.

Design and fabrication of a compact microstrip low-pass filter with ultra-wide stopband and sharp roll-off-rate

Abstract: Microstrip low-pass filters (LPFs) with good performance are used in most telecommunication systems. In this study, a modified T-shaped hairpin resonator is used to design LPF, and suppression cell...

The LPF with improved stopband response designed for wideband microwave detectors

Abstract: To achieve an improved stopband response including expanded stopband width, increased rejection level, and a smooth S11 phase response, a lowpass filter (LPF) is proposed based on the suspended microstrip line with naturally high characteristic impedance and the radial stub with intrinsic transmission zero. The usually unmentioned phase response, are critical to obtaining a wide and flat operating band for the microwave detector, since a smooth phase response exerts small load effects to the diode. As a demonstration, a detector employing the LPF is fabricated and measured. The measured results show that a wide operating band from 1.8 to 13.5 GHz with flat detection outputs of ripple less than 1 dB is obtained for the detector, which coincides with the smooth-phase range of the LPF.