A W-band subharmonically pumped monolithic GaAs-based HEMT gate mixer

A W-band high electron mobility transistor (HEMT) subharmonically pumped (SHP) gate mixer is designed with fixed LO frequency operation. it is fabricated on a 4-mil substrate using 0.15-/spl mu/m GaAs pHEMT monolithic microwave integrated circuit (MMIC) process. the on-wafer measurement results show that the best conversion loss is about 4.7 dB in the W-band, as a 11-dbm 42-GHz low observable (LO) signal is pumped. To our knowledge, this is the first result on low conversion-loss W-band MMIC SHP HEMT gate mixer.     

A Study of W-Band Subharmonically Pumped Mixer

A W-band subharmonically pumped mixer with packaged Schottky diodes has been developed. The design and performance of this mixer are described in detail. A new method for measuring the embedding network parameters of the subharmonically pumped mixer has been developed and the measurement bas been carried out directly at 2f/sub LO/ and 2f/sub LO/+-f/sub if/. A special program for the analysis of the subharmonically pumped mixer has been developed, and computed results are given in comparison with measured results.     

A D‐Band Balanced Subharmonically‐Pumped Resistive Mixer Based on 100‐nm mHEMT Technology

A D‐band subharmonically‐pumped resistive mixer has been designed, processed, and experimentally tested. The circuit is based on a 180° power divider structure consisting of a Lange coupler followed by a λ/4 transmission line (at local oscillator (LO) frequency). This monolithic microwave integrated circuit (MMIC) has been realized in coplanar waveguide technology by using an InAlAs/InGaAs‐based metamorphic high electron mobility transistor process with 100‐nm gate length. The MMIC achieves a measured conversion loss between 12.5 dB and 16 dB in the radio frequency bandwidth from 120 GHz to 150 GHz with 4‐dBm LO drive and an intermediate frequency of 100 MHz. The input 1‐dB compression point and IIP3 were simulated to be 2 dBm and 13 dBm, respectively.     

Low-noise submillimeter receivers using single-diode harmonicmixers

Submillimeter Schottky diode mixers operating on the second LO harmonic have been built, achieving noise temperatures only 1.3-1.5 times higher than those of fundamental mixers at the same frequency. These mixers use only a single diode junction for ease of fabrication, and allow construction of a complete receiver of greatly reduced complexity relative to those using fundamental mixers. Several such mixers have been built for frequencies from 490 to 670 GHz. These mixers are pumped by frequency multipliers driven by InP Gunn oscillators, with a net LO input which is typically 2 mW. The best results are receiver noise temperatures of 4600 K SSB at 550 GHz and 5100 K at 665 GHz. The theory of mixer noise and conversion loss agrees fairly well with the experimental results, and this same theory predicts that a third-harmonic mixer near 1 THz would also achieve excellent performance     

A 5-10 GHz octave-band AlGaAs/GaAs HBT-Schottky diodedown-converter MMIC

The authors describe an AlGaAs/GaAs heterojunction bipolar transistor (HBT) X-band down-converter monolithic microwave integrated circuit (MMIC) which integrates a double double-balanced Schottky mixer and five stages of HBT amplification to achieve greater than 30 dB conversion gain over an RF bandwidth from 5 to 10 GHz. In addition, an output IP3 as high as +15 dBm has been achieved. The Schottky diodes are constructed from the existing N^$collector and N⁺ subcollector layers of the HBT molecular beam epitaxy (MBE) device structure. A novel HBT amplifier topology employing active feedback which provides wide bandwidth in a compact area is used for the RF, LO, and IF amplifier stages. The complete down-converter MMIC is realized in a 3.6×3.4 mm² area, is self-biased through a 6 V supply, and consumes 530 mW. This MMIC represents the highest complexity X-band down-converter MMIC demonstrated using GaAs HBT-Schottky diode technology     

Analysis and Design of a Novel $times$4 Subharmonically Pumped Resistive HEMT Mixer

In this paper, a novel topology of an HEMT-based subharmonically pumped resistive mixer (SHPRM) is presented, i.e., the times4SHPRM. The presented topology requires only a quarter of the local oscillator (LO) frequency compared to a fundamentally pumped mixer (e.g., 15 instead of 60 GHz in a 60-GHz system). This reduction in required LO frequency provides a significant reduction in complexity of the overall radio front-end and reduces the dc power consumption as well as the occupied chip area. Thus, the times4SHPRM provides a significant cost reduction for a millimeter-wave system. Furthermore, the times4SHPRM can be used for both up- and down-conversion and it can be implemented in any field-effect transistor technology. The principle of the times4SHPRM is presented and wave analysis is applied in order to investigate the fundamental limitations of this mixer topology. For an evaluation of the times4SHPRM topology, three different monolithic microwave integrated circuits (MMICs) were designed and manufactured in the same MMIC metamorphic HEMT technology. Besides measured performance of the times4SHPRM, a traditional times2SHPRM and a single-ended resistive mixer were implemented and their performances are presented and compared. All of these MMICs operate with a 60-GHz RF frequency and employ LO signals close to 15, 30, and 60 GHz, respectively.     

三毫米波段二次谐波混频器

采用微带结构研制出三毫米波段二次谐波混频器.该混频器核心器件采用型号为MS8251的GaAs梁式引线肖特基势垒二极管对.根据二次谐波混频器对本振、射频和中频网络的要求,先用谐波平衡法分析出反向并联二极管对在本振信号单独激励下的大信号阻抗,由此设计出本振网络;然后模拟出该器件在大信号本振激励下的小信号射频输入阻抗,并由此...     

Design and fabrication of 94 GHz MMIC single balanced resistive mixer without IF balun

In this paper, a 94 GHz microwave monolithic integrated circuit (MMIC) single balanced resistive mixer affording high LO-to-RF isolation was designed without an IF balun. The single balanced resistive mixer, which does not require an external IF balun, was designed using a 0.1 μm InGaAs/InAlAs/GaAs metamorphic high electron mobility transistor (HEMT). The designed MMIC single balanced resistive mixer was fabricated using the 0.1 μm MHEMT MMIC process. From the measurement, conversion loss of the single balanced resistive mixer was 14.7 dB at an LO power of 10 dBm. The P_1 dB (1 dB compression point) values of the input and output were 10 dBm and −5.3 dBm, respectively. The LO-to-RF isolation of the single balanced resistive mixer was −35.2 dB at 94.03 GHz. The single balanced resistive mixer in this work provided high LO-to-RF isolation without an IF balun.     

Broadband single- and double-balanced resistive HEMT monolithicmixers

A double-balanced (DB) 3-18 GHz and a single-balanced (SB) 2-16 GHz resistive HEMT monolithic mixer have been successfully developed. The DB mixer consists of a AlGaAs/InGaAs HEMT quad, an active LO balun, and two passive baluns for RF and IF. At 16 dBm LO power, this mixer achieves the conversion losses of 7.5-9 dB for 4-13 GHz RF and 7.5-11 dB for 3-18 GHz RF. The SB mixer consists of a pair of AlGaAs/InGaAs HEMT's, an active LO balun, a passive IF balun and a passive RF power divider. At 16 dBm LO power, this mixer achieves the conversion losses of 8-10 dB for 4-15 GHz RF and 8-11 dB for 2-16 GHz RF. The simulated conversion losses of both mixers are very much in agreement with the measured results. Also, the DB mixer achieves a third-order input intercept (IP₃) of +19.5 to +27.5 dBm for a 7-18 GHz RF and 1 GHz IF at a LO drive of 16 dBm while the SB mixer achieves an input IP ₃ of +20 to +28.5 dBm for 2 to 16 GHz RF and 1 GHz IF at a 16 dBm LO power. The bandwidth of the RF and LO frequencies are approximately 6:1 for the DB mixer and 8:1 for the SB mixer. The DB mixer of this work is believed to be the first reported DB resistive HEMT MMIC mixer covering such a broad bandwidth     

毫米波单片混频器的研制

采用0.18μm G aA s PHEM T工艺,设计和研制了34~40 GH z毫米波单片混频器。该混频器选择了单平衡结构,采用180°电桥结构改善LO-RF的隔离度,并修改了该结构以方便布版。在39 GH z频点上,该混频器的插入损耗小于7.2 dB、LO-RF隔离度大于32 dB。     

宽带混频器的优化设计

采用0.25μm GaAs赝配高电子迁移率晶体管(PHEMT)工艺设计并实现了一款单片宽带混频器.该混频器采用双平衡混频器结构,以串联的两个漏源相连的PHEMT作为环形二极管电桥中的二极管以提升混频器线性度.本振巴伦和射频巴伦均采用螺旋线式Marchand巴伦,为降低巴伦的幅度及相位不平衡度,采用遗传算法对巴伦的几何参数进行了优化设计.该混频器电路采用0.25 μm GaAs PHEMT工艺实现,芯片面积为1.5mm×1.1 mm.测试结果表明,当本振功率为20 dBm时,变频损耗小于7 dB,输入三阶交调点ⅡP3大于22 dBm.本振端口到射频端口和中频端口的隔离度均大于30 dB.     

60 GHz MMIC double balanced Gilbert mixer in mHEMT technology with integrated RF, LO and IF baluns

A 60 GHz MMIC double balanced Gilbert mixer (DBGM) with integrated RF, LO and IF baluns has been designed, fabricated in an mHEMT MMIC technology and characterised with probed measurements. Although a standard mixer topology for integrated circuits in the low gigahertz region, the DBGM has had very little impact in the millimetre-wave range. To the authors' knowledge, the presented DBGM operates at the highest RF frequency ever published for any FET-based Gilbert type mixer, double or single balanced. A measured down conversion gain of 1.5 dB at 60 GHz is obtained with a DC power consumption of 300 mW. Further, IF bandwidth, isolation between the LO, RF and IF ports, 1 dB compression point for the RF input, and LO input power is presented     

Prediction of Mixer Intermodulation Levels as Function of Local Oscillator Power

During intermodulation testing with diode mixers an increase of intermodulation interference was observed due to an increase of LO power incident to the mixer. This phenomenon conflicted with the theory that increase of LO power reduces intermodulation output of the diode mixer. In these tests the intermodulation decreased as expected when the LO power was further increased. Results of a theoretical and experimental study of how the level of incident LO power affects the intermodulation output levels emanating from the mixer are presented. The predicted results lead to the following experimentally verified conclusions. 1) A drop in power at some intermodulation frequencies occurs for an increase of LO power, depending on LO operating point and order of intermodulation. 2) Power at each intermodulation frequency will repeatedly increase, reach a maximum, and then decrease as power in LO signal increases, where the number of repetitions follows the orders of intermodulation. 3) The maximum intermodulation power at low-order intermodulation frequencies occurs for higher LO power than higher order intermodulation frequencies. LO power operating point is shown to be a significant factor in mixer intermodulation consideration. Application of these results to receiver intermodulation improvement is discussed.     

Measurements on a 215-GHz subharmonically pumped waveguide mixerusing planar back-to-back air-bridge Schottky diodes

This paper presents design and performance data for a 215-GHz subharmonically pumped waveguide mixer using an antiparallel-pair of planar air-bridge-type GaAs Schottky-barrier diodes. The waveguide design is a prototype for a 640-GHz system and uses split-block rectangular waveguide with a 2:1 width-to-height ratio throughout. The measured mixer noise and conversion loss are below that of the best reported whisker contacted or planar-diode mixers using the subharmonic-pump configuration at this frequency. In addition, the required local oscillator power is as low as 3 mW for the unbiased diode pair, and greater than 34 dB of LO noise suppression is observed. Separate sideband calibration, using a Fabry-Perot filter, indicates that the mixer can be tuned for true double sideband response at an intermediate frequency of 1.5 GHz. Microwave scale model measurements of the waveguide mount impedances are combined with a mixer nonlinear analysis computer program to predict the mixer performance as a function of anode diameter, anode finger inductance, and pad-to-pad fringing capacitance. The computed results are in qualitative agreement with measurements, and indicate that careful optimization of all three diode parameters is necessary to significantly improve the mixer performance     

GaAs MMIC MESFET混频器性能比较

给出了几种 Ga As MESFET单片混频器结构与芯片测试结果比较。实验表明 ,在相同本振功率激励下 Ga As MMIC双栅混频器具有良好变频特性 ,栅混频器指标次之 ,漏混频器结构最简单 ,但变频特性不如前两种。另外 ,单片巴仑双平衡混频器具有高的动态范围和宽频段工作特点。     

Millimeter-wave-band amplifier and mixer MMICs using a broad-band45° power divider/combiner

This paper demonstrates millimeter-wave-band amplifier and mixer monolithic microwave integrated circuits (MMIC's) using a broad-band 45° power divider/combiner. At first, we propose a broad-band 45° power divider/combiner, which combines a Wilkinson divider/combiner, 45° delay line, and 90° short stub. A coupling loss of 4.0±0.2 dB and a return loss and an isolation of more than 19 dB with 45±1° phase difference was obtained from 17 to 22 GHz for the fabricated K-band MMIC 45° power divider/combiner. Next, a parallel amplifier using the broad-band 45° power divider/combiner, which can be used in a power-combining circuit configuration requiring no isolator, is shown. Comparing the transmitter intermodulation generated in the parallel amplifier using the broad-band 45° power divider/combiner and that generated in the one using the conventional type, the broad-band suppression effect was confirmed. Finally, an application of the broad-band 45° power divider/combiner to a single-sideband (SSB) subharmonically pumped (SHP) mixer requiring no IF switch is shown. In an RF frequency range from 22.89 to 26.39 GHz, the fabricated K-band MMIC mixer achieved (for up-conversion) the good results of more than -13-dB conversion gain and more than 24-dB image-rejection ratio. These contribute significantly to the miniaturization of millimeter-wave communication equipment     

A monolithic double-balanced direct conversion mixer with an integrated wideband passive balun

This paper presents the design and performance characteristics of a 20-40 GHz monolithic double-balanced direct conversion mixer implemented using InGaP/GaAs HBT process. The compact MMIC mixer makes use of a Gilbert-cell multiplier and utilizes a broadband monolithic passive balun that has been developed for MMIC applications. The new balun makes use of multidielectric layer structure to achieve a broadband performance in a simple coplanar configuration. A measured return loss better than 15 dB, with a maximum insertion loss of 4.5 dB including the 3-dB power splitting loss has been achieved over the band from 15 to 45 GHz. Operated as a downconverter mixer, the newly developed direct conversion mixer achieves a measured conversion gain of 16 dB given an RF signal at 30 GHz, LO drive of 5 dBm and a downconverted baseband signal at 10 MHz. The mixer IP3 occurs at an output power of 4 dBm while the IP2 occurs at an output power of 11 dBm.     

A single-chip GaAs MMIC image-rejection front-end for digitalEuropean cordless telecommunications

An active image-rejection filter is presented in this paper, which applies actively coupled passive resonators. The filter has very low noise and high insertion gain, which may eliminate the use of a low-noise amplifier (LNA) in front-end applications. The GaAs monolithic-microwave integrated-circuit (MMIC) chip area is 3.3 mm² . The filter has 12-dB insertion gain, 45-dB image rejection, 6.2-dB noise figure, and dissipates 4.3 mA from a 3-V supply. An MMIC mixer is also presented. The mixer applies two single-gate MESFETs on a 2.2-mm² GaAs substrate. The mixer has 2.5-dB conversion gain and better than 8-dB single-sideband (SSB) noise figure with a current dissipation of 3.5 mA applying a single 5-V supply. The mixer exhibits very good local oscillator (LO)/RF and LO/IF isolation of better than 30 and 17 dB, respectively, Finally, the entire front-end, including the LNA, image rejection filter, and mixer functions is realized on a 5.7-mm ² GaAs substrate. The front-end has a conversion gain of 15 dB and an image rejection of more than 53 dB with 0-dBm LO power. The SSB noise figure is better than 6.4 dB, The total power dissipation of the front-end is 33 mW. The MMIC's are applicable as a single-block LNA and image-rejection filter, mixer, and single-block front-end in digital European cordless telecommunications. With minor modifications, the MMIC's can be applied in other wireless communication systems working around 2 GHz, e.g., GSM-1800 and GSM-1900     

A highly integrated wideband millimeter-wave MMIC converter using0.25-μm P-HEMT technology

A highly integrated wideband converter that was designed to upconvert the entire 6- to 18-GHz input RF frequency band to a 22-GHz intermediate frequency using a 28- to 40-GHz local oscillator (LO) is described. The circuit was designed using 0.25-μm pseudomorphic HEMT technology. The converter incorporates a three-stage RF amplifier, a three-stage LO amplifier, and an active balanced mixer, all integrated on a chip 96 mil×96 mil in size. The upconverter monolithic microwave integrated circuit (MMIC) has an average of 10-dB conversion gain across the full 6-18-GHz input band     

0.67 THz宽带谐波混频器设计

为研制太赫兹多频段高灵敏度探测仪,依靠太赫兹砷化镓平面肖特基二极管的非线性特性,结合石英薄膜工艺,设计了宽带0.67 THz谐波混频器,并分析了砷化镓平面肖特基二极管性能表征参数指标对太赫兹混频器性能的影响。0.67 THz谐波混频器采用整体综合的设计方法,结合电气仿真软件ADS和电磁仿真软件HFSS,优化电路中不连续性微带与波导之间的电磁空间耦合效率,以混频器的变频损耗为优化目标,最终实现0.67 THz谐波混频器仿真设计。0.62~ 0.72 THz射频范围内,混频器单边带最低变频损耗小于8 dB,本振功率小于4 mW,本振端口与中频端口、射频端口与中频端口之间隔离度大于-30 dB。