Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972890
Silvia Fabiani, D. Mencarelli, A. di Donato, T. Monti, G. Venanzoni, A. Morini, T. Rozzi, M. Farina
In this work we describe the application of a dual-channel scanning probe microscope performing simultaneously Scanning Tunneling Microscopy (STM) and wide-band Near Field Scanning Microwave Microscopy (wide-band SMM) - developed by ourselves- to a graphene flake. In our system we introduce a conversion in Time-Domain to discriminate the desired information, achieving high quality microwave images with nanometric resolution. The graphene sample is deposited on a substrate of SiO2 with an additional deposition of gold (a contact finger). The preliminary measurements seem to show evidence of localized change of impedance near the edge of the flake.
{"title":"Broadband Scanning Microwave Microscopy investigation of graphene","authors":"Silvia Fabiani, D. Mencarelli, A. di Donato, T. Monti, G. Venanzoni, A. Morini, T. Rozzi, M. Farina","doi":"10.1109/MWSYM.2011.5972890","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972890","url":null,"abstract":"In this work we describe the application of a dual-channel scanning probe microscope performing simultaneously Scanning Tunneling Microscopy (STM) and wide-band Near Field Scanning Microwave Microscopy (wide-band SMM) - developed by ourselves- to a graphene flake. In our system we introduce a conversion in Time-Domain to discriminate the desired information, achieving high quality microwave images with nanometric resolution. The graphene sample is deposited on a substrate of SiO2 with an additional deposition of gold (a contact finger). The preliminary measurements seem to show evidence of localized change of impedance near the edge of the flake.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131289850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972901
A. Kheirkhahi, P. Asbeck, L. Larson
A baseband modulation technique is proposed to improve the efficiency and linearity of Class-A/AB radio frequency (RF) power amplifiers (PAs). The baseband load impedance is optimized, and the input envelope — along with the RF signal — is fed to the PA input. The resulting baseband modulation of the drain increases the saturated RF output power and improves the linearity for a given dc power consumption. A 2GHz HFET power amplifier exhibited a significant improvement in peak PAE from 40% to 54% for a two-tone input and from 23% to 27% for a 5MHz BW 64-QAM signal.
{"title":"Enhanced Class-A/AB mobile terminal power amplifier efficiency by input envelope injection and “self” envelope tracking","authors":"A. Kheirkhahi, P. Asbeck, L. Larson","doi":"10.1109/MWSYM.2011.5972901","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972901","url":null,"abstract":"A baseband modulation technique is proposed to improve the efficiency and linearity of Class-A/AB radio frequency (RF) power amplifiers (PAs). The baseband load impedance is optimized, and the input envelope — along with the RF signal — is fed to the PA input. The resulting baseband modulation of the drain increases the saturated RF output power and improves the linearity for a given dc power consumption. A 2GHz HFET power amplifier exhibited a significant improvement in peak PAE from 40% to 54% for a two-tone input and from 23% to 27% for a 5MHz BW 64-QAM signal.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115579675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972997
P. Staecker
Ted Saad's professional and volunteer life was marked by accomplishments, service, mentorship, and innovation. For those of us who had the honor and pleasure of working with him in the preparatory years leading to the 1991 IEEE International Microwave Symposium, the excitement, urgency, and success of the MIT Radiation Laboratory were revealed.
{"title":"Ted Saad and the 1991 RadLab Celebration","authors":"P. Staecker","doi":"10.1109/MWSYM.2011.5972997","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972997","url":null,"abstract":"Ted Saad's professional and volunteer life was marked by accomplishments, service, mentorship, and innovation. For those of us who had the honor and pleasure of working with him in the preparatory years leading to the 1991 IEEE International Microwave Symposium, the excitement, urgency, and success of the MIT Radiation Laboratory were revealed.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124128677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972717
C. Patel, Gabriel M. Rebeiz
This paper presents a temperature stable metal-contact RF MEMS switch capable of handling >5 W of RF power. The device achieves 0.7 – 1.5 mN of contact force for actuation voltages of 80 – 90 V, with a restoring force of 0.63 mN. Furthermore, the device is insensitive to stress effects and temperature. Temperature measurements showed excellent thermal stability - no deflection in the beam, and a change in pull-in voltage of only 4 V from 25 – 125 °C. The switch was tested under prolonged (>24 hrs) high-power RF conditions with excellent reliability.
{"title":"A high power (>5 W) temperature stable RF MEMS metal-contact switch with orthogonal anchors and force-enhancing stoppers","authors":"C. Patel, Gabriel M. Rebeiz","doi":"10.1109/MWSYM.2011.5972717","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972717","url":null,"abstract":"This paper presents a temperature stable metal-contact RF MEMS switch capable of handling >5 W of RF power. The device achieves 0.7 – 1.5 mN of contact force for actuation voltages of 80 – 90 V, with a restoring force of 0.63 mN. Furthermore, the device is insensitive to stress effects and temperature. Temperature measurements showed excellent thermal stability - no deflection in the beam, and a change in pull-in voltage of only 4 V from 25 – 125 °C. The switch was tested under prolonged (>24 hrs) high-power RF conditions with excellent reliability.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124449757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972625
T. Wada, T. Hasegawa, M. Koshino, T. Okada
A novel broadband Core-Isolator for modules of multi-standard and multi-band mobile handsets has been developed successfully. A new circuit configuration for extending the isolation frequency band is proposed. The equations of the insertion loss and the isolation bandwidth of a two-port isolator with resonant elements are derived from equivalent circuit using perturbation theory. They show that the isolation bandwidth gets wider depending on the ratio of inductor and capacitor of resonant elements without increasing the insertion loss. A 1.5 × 0.9 × 0.4 mm3 Core-Isolator with two electrodes of asymmetrical structure has been fabricated, which is mounted on a module substrate with resonant elements. It has an insertion loss of 0.5dB and an isolation of 10dB at 824–915MHz which is twice wider than conventional one.
{"title":"Low-profile broadband Core-Isolator for multi-band module","authors":"T. Wada, T. Hasegawa, M. Koshino, T. Okada","doi":"10.1109/MWSYM.2011.5972625","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972625","url":null,"abstract":"A novel broadband Core-Isolator for modules of multi-standard and multi-band mobile handsets has been developed successfully. A new circuit configuration for extending the isolation frequency band is proposed. The equations of the insertion loss and the isolation bandwidth of a two-port isolator with resonant elements are derived from equivalent circuit using perturbation theory. They show that the isolation bandwidth gets wider depending on the ratio of inductor and capacitor of resonant elements without increasing the insertion loss. A 1.5 × 0.9 × 0.4 mm3 Core-Isolator with two electrodes of asymmetrical structure has been fabricated, which is mounted on a module substrate with resonant elements. It has an insertion loss of 0.5dB and an isolation of 10dB at 824–915MHz which is twice wider than conventional one.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124517600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972837
Xun Luo, Jianguo Ma, E. Li
A miniaturized bandpass filter with high selectivity and wide stopband is proposed using the dual-layer structure. The broadside-coupled microstrip/interdigital defected ground structure (DGS) cell is introduced to allocate center frequency with two close transmission zeros. Based on the proposed cells, an interdigital-coupled scheme is employed to achieve strong passband enhancement with high selectivity. To further improve the passband perfomance and extend the stopband bandwidth, the defected microstrip structure (DMS) is proposed. The measured filter operated at ƒ0 of 2.6 GHz has the merits of an excellent selectivity (i.e., strong attenuation slope with 420.9 dB/GHz in the lower and 484.9 dB/GHz in the upper transition bands) and wide stopband up to 3.75 ƒ0.
{"title":"Miniaturized bandpass filter with high selectivity and wide stopband using dual-layer structure","authors":"Xun Luo, Jianguo Ma, E. Li","doi":"10.1109/MWSYM.2011.5972837","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972837","url":null,"abstract":"A miniaturized bandpass filter with high selectivity and wide stopband is proposed using the dual-layer structure. The broadside-coupled microstrip/interdigital defected ground structure (DGS) cell is introduced to allocate center frequency with two close transmission zeros. Based on the proposed cells, an interdigital-coupled scheme is employed to achieve strong passband enhancement with high selectivity. To further improve the passband perfomance and extend the stopband bandwidth, the defected microstrip structure (DMS) is proposed. The measured filter operated at ƒ0 of 2.6 GHz has the merits of an excellent selectivity (i.e., strong attenuation slope with 420.9 dB/GHz in the lower and 484.9 dB/GHz in the upper transition bands) and wide stopband up to 3.75 ƒ0.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"277 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114608557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972789
R. Pokharel, Xin Liu, R. Dong, A. B. Dayang, H. Kanaya, K. Yoshida
This paper presents a design of an improved on-chip open loop resonator band pass filter (OLR-BPF) for 60 GHz millimeter-wave applications in 0.18 µm CMOS technology. The proposed on-chip BPF employs the folded open loop structure on patterned ground shields. The adoption of a folded structure for the OLR-BPF and utilization of two transmissions zero permits a compact size and high selectivity for the BPF. In addition, the patterned ground shields obviously slowed down the guided waves, which enables a further reduction of the physical length of the resonator and finally an improvement of the insertion loss of the BPF. By comparison between the electromagnetic (EM) simulations and measurement results, the proposed BPF has the center frequency of 59 GHz, insertion loss 2.77 dB, band width 14 GHz, return loss is less than 27.5 dB, and chip size 910×650 µm2 (including bonding pads).
{"title":"60GHz-band low loss on-chip band pass filter with patterned ground shields for millimeter wave CMOS SoC","authors":"R. Pokharel, Xin Liu, R. Dong, A. B. Dayang, H. Kanaya, K. Yoshida","doi":"10.1109/MWSYM.2011.5972789","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972789","url":null,"abstract":"This paper presents a design of an improved on-chip open loop resonator band pass filter (OLR-BPF) for 60 GHz millimeter-wave applications in 0.18 µm CMOS technology. The proposed on-chip BPF employs the folded open loop structure on patterned ground shields. The adoption of a folded structure for the OLR-BPF and utilization of two transmissions zero permits a compact size and high selectivity for the BPF. In addition, the patterned ground shields obviously slowed down the guided waves, which enables a further reduction of the physical length of the resonator and finally an improvement of the insertion loss of the BPF. By comparison between the electromagnetic (EM) simulations and measurement results, the proposed BPF has the center frequency of 59 GHz, insertion loss 2.77 dB, band width 14 GHz, return loss is less than 27.5 dB, and chip size 910×650 µm2 (including bonding pads).","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117316371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972703
Yen-Liang Yeh, Hong-Yeh Chang
This paper presents linearity enhancement of CMOS device for microwave amplifier applications. The proposed method is based on a modified third-order transconductance (gm3) cancellation technique and the device is fabricated in a 0.13 µm CMOS process. For the NMOS device with the proposed gm3 cancellation technique, the third-order intermodulation distortion (IMD3) is improved by 15 dB as compared to the conventional single device. Two Ka-band CMOS amplifiers with and without the linearization are successfully evaluated. With the linearization, the measured IMD3 is enhanced by 14 dB, and the adjacent channel power ratio (ACPR) of the amplifier is improved by 7 dB for a 64-QAM modulation signal. Moreover, the linearization scheme is easily applied to the microwave amplifier and mixer designs without extra dc power consumption.
本文介绍了用于微波放大器的CMOS器件的线性度增强。该方法基于改进的三阶跨导(gm3)对消技术，器件采用0.13 μ m CMOS工艺制造。对于采用gm3对消技术的NMOS器件，其三阶互调失真(IMD3)比传统单器件提高了15 dB。成功地评估了两个ka波段CMOS放大器的线性化和不线性化。对64-QAM调制信号进行线性化后，测量到的IMD3提高了14 dB，相邻通道功率比(ACPR)提高了7 dB。此外，线性化方案易于应用于微波放大器和混频器设计，而无需额外的直流功耗。
{"title":"Linearity enhancement of CMOS device using a modified third-order transconductance cancellation technique for microwave amplifier","authors":"Yen-Liang Yeh, Hong-Yeh Chang","doi":"10.1109/MWSYM.2011.5972703","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972703","url":null,"abstract":"This paper presents linearity enhancement of CMOS device for microwave amplifier applications. The proposed method is based on a modified third-order transconductance (gm3) cancellation technique and the device is fabricated in a 0.13 µm CMOS process. For the NMOS device with the proposed gm3 cancellation technique, the third-order intermodulation distortion (IMD3) is improved by 15 dB as compared to the conventional single device. Two Ka-band CMOS amplifiers with and without the linearization are successfully evaluated. With the linearization, the measured IMD3 is enhanced by 14 dB, and the adjacent channel power ratio (ACPR) of the amplifier is improved by 7 dB for a 64-QAM modulation signal. Moreover, the linearization scheme is easily applied to the microwave amplifier and mixer designs without extra dc power consumption.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116005206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972918
G. Stantchev, D. Chernin, T. Antonsen, B. Levush
We present a framework for efficient, physics-based computer simulation of complex time-dependent waveforms (i.e. wide-band, with large number of frequency components) in nonlinear amplifiers with memory. It is built upon a well established pseudo-spectral, multi-frequency, large-signal code and relies on an adaptive algorithm for signal splitting and splicing in the time domain. Included in the model, and calculated from first-principles, are memory effects, such as dispersion and wave reflections. We validate our approach on such complex waveforms by operating the simulation kernel in the large-signal, nonlinear regime and comparing against the output of the benchmarked serial version.
{"title":"Accelerated simulation of complex waveforms in nonlinear amplifiers with memory","authors":"G. Stantchev, D. Chernin, T. Antonsen, B. Levush","doi":"10.1109/MWSYM.2011.5972918","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972918","url":null,"abstract":"We present a framework for efficient, physics-based computer simulation of complex time-dependent waveforms (i.e. wide-band, with large number of frequency components) in nonlinear amplifiers with memory. It is built upon a well established pseudo-spectral, multi-frequency, large-signal code and relies on an adaptive algorithm for signal splitting and splicing in the time domain. Included in the model, and calculated from first-principles, are memory effects, such as dispersion and wave reflections. We validate our approach on such complex waveforms by operating the simulation kernel in the large-signal, nonlinear regime and comparing against the output of the benchmarked serial version.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116030233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972638
X. Meng, M. Tofighi, A. Rosen
The monitoring of acute and later stages of changes of intracranial pressure (ICP) is of great importance in studies of the effects of hydrocephalus and traumatic brain injury. It also aids in determining the outcome of treatment. A digital prototype for wireless ICP measurement based on Texas Instrument's CC2500 2.4 GHz transceiver and MSP430 ultra-low-power microcontroller has been designed, investigated, and tested. In-vitro evaluations under different circumstances are described to demonstrate the repeatability, stability, and reliability of the device.
{"title":"Digital microwave system for monitoring intracranial pressure in hydrocephalic and traumatic brain injury patients","authors":"X. Meng, M. Tofighi, A. Rosen","doi":"10.1109/MWSYM.2011.5972638","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972638","url":null,"abstract":"The monitoring of acute and later stages of changes of intracranial pressure (ICP) is of great importance in studies of the effects of hydrocephalus and traumatic brain injury. It also aids in determining the outcome of treatment. A digital prototype for wireless ICP measurement based on Texas Instrument's CC2500 2.4 GHz transceiver and MSP430 ultra-low-power microcontroller has been designed, investigated, and tested. In-vitro evaluations under different circumstances are described to demonstrate the repeatability, stability, and reliability of the device.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121863015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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