Conversion gain in millimeter wave quasi-particle heterodyne mixers

The physical mechanisms which give rise to conversion gain in SIS quasi-particle mixers are studied. It is shown that theS-shape tunneling structure at the gap voltage of theI- Vcurve is essential in achieving conversion gain. In the development of SIS quasi-particle mixers, a new approach is used to analyze the embedding network of the mixing experiment. The method described in this paper has the advantage over conventional methods that no separate measurements are necessary. In order to obtain a complete picture of the performance of SIS quasi-particle mixers, the photon-assisted tunneling theory used by Tucker to describe quasi-particle mixing is extended here to include pair current contribution. Based on this complete quantum theory, the effects of the Josephson noise on SIS quasi-particle mixing is discussed and an upper frequency limit of SIS quasi-particle mixing is estimated.     

Monolithic rat-race mixers for millimeter waves

In this paper, we report on fully monolithic millimeter-wave Schottky-barrier diode (SBD) down-converters with an IF amplifier using heterojunction bipolar transistors (HBT's). A rat-race circuit is used for the mixer, and is analyzed using a harmonic-balance simulator. The measured conversion gain and the isolation are 7.1 and 29 dB in the V-band design, and 8.0 and 25 dB in the W-band design, respectively. The conversion gains are matched well with the circuit simulation     

Spurious-response suppression evaluation of space qualified millimeter wave mixers: A distributed and parasitic effects approach

In millimeter wave space communications packaged devices are usually involved for environmental and EMI protection reasons. Therefore, distributed and parasitic effect considerations become an important issue for the design and performance evaluation of space qualified frequency translating devices. Indeed, the accuracy of the usually adapted exponential I/V curve of an ideal (distributed and parasitic effects-free) diode, is considered to be not adequate for the prediction of spurious-response suppressions related to such millimeter wave diode mixers. In this paper the effects of parasitic [C_p] and distributed [C_j(ν)] diode capacitance in a single-tone spurious products evaluation of a commercially available Schottky-barrier based single-ended mixer, are investigated for frequencies up to 120 GHz. The reported results accurately demonstrate that the suppression of 3th and 5th order spurious products is strongly related to the variation of C_p and C_j(ν) with frequency.     

Field analysis and CAD millimeter wave VCO

In this paper, the CAD of millimeter wave VCO is investigated based on a frequency-domain harmonic balance technique, where the external-circuit mutual impedances looking outside from two active devices are calculated in terms of a rigorous definition and a mixed technique of modes expansion, Galerkin method and collocation method. The CAD results are in agreement with the experimental results, which shows the raliability of the presented model and optimisation.     

Accurate evaluation of a millimeter wave compact range using planar near-field scanning

Significant progress has been made in recent years on planar near-field measurements for antenna calibrations. Such measurements are also useful in the alignment and evalnation of compact ranges because they provide more information than a limited number of analogue plots in one dimension. Contour plots of amplitude and phase data obtained from more complete two-dimensional measurements precisely and accurately locate sources of problems in the range reflector, with phase contour plots being more useful as diagnostic tools.     

Cryogenic cooling of mixers for millimeter and centimeter wavelengths

It is shown theoretically that cryogenically cooling a Schottky-barrier mixer only slightly increases the conversion loss while giving a considerable reduction in mixer noise. The d.c. bias and local oscillator drive must be appropriately scaled. Experimental results indicate that in conjunction with a cooled paramp IF amplifier, single-sideband (SSB) receiver noise temperatures of ~350 K at 85 GHz, and ~260 K at 33 GHz are presently obtainable-an improvement by a factor of 6 at 85 GHz and 4 at 33 GHz over current room-temperature mixer receivers. An unexplained source of noise within the diodes has been observed and if this can be eliminated a further factor of 2 improvement in noise temperature will be obtained.     

Superconducting detectors and mixers for millimeter and submillimeter astrophysics

Superconducting detectors will play an increasingly significant role in astrophysics, especially at millimeter through far-IR wavelengths, where the scientific opportunities include key problems in astronomy and cosmology. Superconducting detectors offer many benefits: outstanding sensitivity, lithographic fabrication, and large array sizes, especially through the recent development of multiplexing techniques. This paper describes the scientific opportunities, the basic physics of these devices, the techniques for radiation coupling, and reviews the recent progress in direct detectors, such as transition-edge bolometers, and the work on tunnel junction (superconductor-insulator-superconductor) and hot-electron mixers.     

The design of quasi-optics power combiner of millimeter wave

This paper presents a theoretical method for design quasi-optics power combiner of solid-state millimeter — wave sources, and gives theory analysis to some problem concerned. Here is the structure:

1. Epitome of microwave power combiner.
2. Gauss light beam and the field distribution in the resonator.
3. The design of the resonator
4. Confocal resonator
5. Objective function
6. The global optimization method and the program flow chart.
7. Example
8. Reference

     

5G毫米波终端测试方法及分析

在5G毫米波终端空口(over the air,OTA)射频一致性测试中,等效全向辐射功率(effective isotropic radiated power,EIRP)和总辐射功率(total radiated power,TRP)类测试是重要的OTA测试项。目前依靠3GPP定义的随机扫描锁定最大波束的方式决定最大EIRP和TRP,但该方法既耗时又缺乏准确性。提出一种非信令的测试方法,相比于目前的EIRP、TRP测试方法,不仅提高了准确性,而且使得非方向性OTA场地作为测量环境成为可能,进一步降低了测试成本和时间成本,并增加了测试环境选择的灵活度。     

Numerical analysis for millimeter wave slot type coupler

The numerical analysis for millimeter wave slot type coupler of overmode waveguide cavity is studied by mode-matching taking account of the thickness of the plate on which the slot is cut. It is found that the higher modes in cavity can be suppressed by proper thickness of the plat and proper dimension of the output waveguide.     

Full-wave analysis of waveguide-to-microstrip transitions for millimeter wave applications

A “full-wave” solution is presented for the waveguide to microstrip transition. The exact Green's function of the transition is used in a moment method procedure. The behavior of the microstrip transition to a rectangular waveguide is studied with respect to the critical dimensions of the microstrip width, length and backshort location. The convergence characteristics of the full wave analysis method are investigated, along with the current distribution and the input impedance. Results given for the return loss is compared with measurements.     

Computer aided design of inverted strip dielectric waveguide millimeter wave ring-resonator and coupler

A computer aided design technique has been developed for the design of millimeter-wave ring resonator and hybrid-ring coupler using inverted strip dielectric waveguides. The scattering matrix analysis for hybrid-ring coupler has also been developed. Numerical results for these components at f₀=80 GHZ with 3-dB coupling have been presented along with the variation of width, spacing, and radii with frequency.     

Accurate millimeter wave antenna phase pattern measurements usingthe differential phase method with three power meters

The novel differential phase measurement method has been demonstrated at millimeter waves using three power meters instead of a phase-sensitive measurement device. Compared to conventional antenna phase measurement methods, the differential phase method provides several advantages. This method requires no rotary joints or flexible cables. Phase-locking of the oscillators is not necessary. It is shown that the phase measurement device can be replaced by three power dividers and three power meters or detectors. The phase patterns measured with three power meters agree well with the measurements carried out using an antenna measurement receiver as well as with the theory     

Global optimization design of quasi-optics fower combiner of solid-state millimeter wave resonator

This paper describes a global optimization design of quasi-optics power combiner of solid-state millimeterwave resonator. It is operated in the frequency range from 50 to 300 GHz using GaAs Gunn diodes. It is shown that sourcearrays containing N² (N=3,5,...2K+1, where k is positive integer) individual elements. It is very efficient power transfer of energy from the source-array to the fractional power of the fundamental beam mode etc.. The RF output power exceeded the sum of the individual diodes to be threefold to sevenfold. And this data is the global optimization solution.     

W波段的毫米波通信

由于其载波频率更高,W波段可支持更大的带宽和更高的传输速率。因为大气损耗小,W波段信号能够进行远距离传输。进行了W波段信号的链路分析,开展了W波段毫米波通信实验的研究。由光生毫米波方法测得W波段传输系统的频率响应在10 dB变化范围内,然后采用电生毫米波系统,进行距离分别为0.8 km,1.2 km及4.4 km的W波段信号的无线传输实验。测得的接收功率分别为-19.77 dBm,-30.85 dBm及-38.61 dBm,验证了W波段信号的远距离传输特性。     

基于BGA互联的毫米波模块三维集成设计

设计了一种利用微波基板作为转接板的毫米波系统级封装（System in Package,SIP）模块。采用球栅阵列(Ball Grid Array,BGA)作为射频信号层间垂直互联传输和隔离结构,实现了三维集成毫米波模块的低损耗垂直传输。对样件测试结果显示,在28~31 GHz频率范围之间,其端口驻波小于1.5,增益大于30 dB。该三维集成结构简单,射频传输性能良好,其体积仅为传统二维平面封装结构的20%,实现了模块的小型化,可广泛用于微波和毫米波电路与系统。