Pub Date : 2017-05-15DOI: 10.1109/INMMIC.2017.7927320
Matthew Love, Daniel Decle Colin, M. Thian
The design and simulation of a Class-E power amplifier with an Inverse Class-B driver are presented. The Inverse Class-B amplifier generates a train of half sinusoids which provides a compromise between using a sine wave and a square wave as the input waveform. The design methodology proposed includes the use of load-pull technique to determine the optimum fundamental-frequency load-impedance of the amplifiers, and a series LC resonator to improve the second-harmonic suppression level. The PA exhibited 26.3 dB gain and 57% PAE at an output power of 21.3 dBm with the second and third harmonics attenuated to 38 and 37.3 dBc respectively.
{"title":"A 5-GHz Class-E power amplifier with an Inverse Class-B driver on 65nm CMOS","authors":"Matthew Love, Daniel Decle Colin, M. Thian","doi":"10.1109/INMMIC.2017.7927320","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927320","url":null,"abstract":"The design and simulation of a Class-E power amplifier with an Inverse Class-B driver are presented. The Inverse Class-B amplifier generates a train of half sinusoids which provides a compromise between using a sine wave and a square wave as the input waveform. The design methodology proposed includes the use of load-pull technique to determine the optimum fundamental-frequency load-impedance of the amplifiers, and a series LC resonator to improve the second-harmonic suppression level. The PA exhibited 26.3 dB gain and 57% PAE at an output power of 21.3 dBm with the second and third harmonics attenuated to 38 and 37.3 dBc respectively.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117327342","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 : 2017-04-22DOI: 10.1109/INMMIC.2017.7927322
P. Freidl, M. Gadringer, Dominik Amschl, Wolfgang Bcõsch
The internet of things (IoT) and its applications demand for solutions for small and low-power communication devices. Overcoming the drawbacks of UHF radio frequency identification (RFID) a shift of the backscatter communication principle to mm-wave frequencies is desirable. With the significant reduction of the transponder size and wider communication bandwidth, many new applications become possible. Demonstrating the feasibility, we implemented a fully functional MMID system in the E-band. Both, the base station and the transponder are investigated and their performance is presented in a system context.
{"title":"mm-Wave RFID for IoT applications","authors":"P. Freidl, M. Gadringer, Dominik Amschl, Wolfgang Bcõsch","doi":"10.1109/INMMIC.2017.7927322","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927322","url":null,"abstract":"The internet of things (IoT) and its applications demand for solutions for small and low-power communication devices. Overcoming the drawbacks of UHF radio frequency identification (RFID) a shift of the backscatter communication principle to mm-wave frequencies is desirable. With the significant reduction of the transponder size and wider communication bandwidth, many new applications become possible. Demonstrating the feasibility, we implemented a fully functional MMID system in the E-band. Both, the base station and the transponder are investigated and their performance is presented in a system context.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124017067","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927319
D. Vegas, Felipe Moreno, M. Ruiz, J. A. García
In this paper, a GaN HEMT class-E power amplifier (PA) has been designed for efficiently operating under variable load resistance at the 750 MHz frequency band. The desired zero voltage switching (ZVS) of the device can be approximated for a wide range of resistive loads, by means of a simple inductive impedance inverter, derived from [1]. The load-pull contours, obtained from simulations, allowed the drain terminating network to be properly adjusted in order to maximize the output power control while at the same time minimizing losses. Once the amplifier was implemented, an efficiency over 76% has been measured at 9.6 dB power back-off, with a peak of 85% at 50 Ω. In addition, the efficiency stays as high as 75% for a 150 MHz frequency range.
{"title":"Efficient class-E power amplifier for variable load operation","authors":"D. Vegas, Felipe Moreno, M. Ruiz, J. A. García","doi":"10.1109/INMMIC.2017.7927319","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927319","url":null,"abstract":"In this paper, a GaN HEMT class-E power amplifier (PA) has been designed for efficiently operating under variable load resistance at the 750 MHz frequency band. The desired zero voltage switching (ZVS) of the device can be approximated for a wide range of resistive loads, by means of a simple inductive impedance inverter, derived from [1]. The load-pull contours, obtained from simulations, allowed the drain terminating network to be properly adjusted in order to maximize the output power control while at the same time minimizing losses. Once the amplifier was implemented, an efficiency over 76% has been measured at 9.6 dB power back-off, with a peak of 85% at 50 Ω. In addition, the efficiency stays as high as 75% for a 150 MHz frequency range.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115503447","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927299
E. Cipriani, P. Colantonio, F. Giannini
This contribution reports the design of an X-band MMIC power amplifier in a 0.25 um GaN technology, proposing for the first time a harmonic manipulation approach on a class C bias condition. Output network provides the power matching condition at fundamental frequency and an open circuit condition at the 3rd harmonic; the correct phase ratio between drain current components is assured by the proper input 2nd harmonic impedance. This solution allows to reach an efficiency higher than 60% in the frequency band 8.5 GHz–9.5 GHz.
本文报道了一种采用0.25 um GaN技术的x波段MMIC功率放大器的设计，首次提出了C类偏置条件下的谐波处理方法。输出网络提供基频处的功率匹配条件和三次谐波处的开路条件;适当的输入二次谐波阻抗保证了漏极电流分量之间的正确相位比。该解决方案允许在8.5 GHz - 9.5 GHz频段内达到超过60%的效率。
{"title":"Class F-C X-band MMIC GaN power amplifier: An extension of waveform engineering approach","authors":"E. Cipriani, P. Colantonio, F. Giannini","doi":"10.1109/INMMIC.2017.7927299","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927299","url":null,"abstract":"This contribution reports the design of an X-band MMIC power amplifier in a 0.25 um GaN technology, proposing for the first time a harmonic manipulation approach on a class C bias condition. Output network provides the power matching condition at fundamental frequency and an open circuit condition at the 3rd harmonic; the correct phase ratio between drain current components is assured by the proper input 2nd harmonic impedance. This solution allows to reach an efficiency higher than 60% in the frequency band 8.5 GHz–9.5 GHz.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124382959","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927310
W. Aouimeur, E. Lauga-Larroze, J. Arnould, J. Moron-Guerra, C. Gaquière, S. Lépilliet, T. Quemerais, D. Gloria, A. Serhan
In this paper, a frequency quadrupler based on a single ended frequency doubler, a new Marchand Balun with Coupled Slow-wave Coplanar Wave (CS-CPW) lines and a balanced frequency doubler in G band is presented and analyzed for in-situ characterization applications. The experimental results of the frequency quadrupler exhibit at 180 GHz a peak output power of −4.5 dBm associate with a linear conversion gain of −5.5 dB, a frequency bandwidth of 160 to 190 GHz and a DC power consumption of 39 mW. This quadrupler has been fabricated in the 55 nm SiGe BiCMOS technology from STMicroelectronics, the chip area is 1850×780 μm2 including the pads.
{"title":"A G band frequency quadrupler in 55 nm BiCMOS for bist applications","authors":"W. Aouimeur, E. Lauga-Larroze, J. Arnould, J. Moron-Guerra, C. Gaquière, S. Lépilliet, T. Quemerais, D. Gloria, A. Serhan","doi":"10.1109/INMMIC.2017.7927310","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927310","url":null,"abstract":"In this paper, a frequency quadrupler based on a single ended frequency doubler, a new Marchand Balun with Coupled Slow-wave Coplanar Wave (CS-CPW) lines and a balanced frequency doubler in G band is presented and analyzed for in-situ characterization applications. The experimental results of the frequency quadrupler exhibit at 180 GHz a peak output power of −4.5 dBm associate with a linear conversion gain of −5.5 dB, a frequency bandwidth of 160 to 190 GHz and a DC power consumption of 39 mW. This quadrupler has been fabricated in the 55 nm SiGe BiCMOS technology from STMicroelectronics, the chip area is 1850×780 μm2 including the pads.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124444815","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927298
T. Huber, R. Quay, W. Bösch
This paper compares the noise performance of the common-source and the cascode topology. Although the cascode topology has several advantages over the common-source stage, the noise performance degrades due to the channel noise and the induced gate noise of the common-gate stage. To underline the theory two multi-decade GaN feedback power amplifiers were designed in common-source and cascode topology, using a submicron AlGaN/GaN MMIC technology on SiC substrate. Both designs achieve 13 dB gain and simultaneously good input and output matching. The 3 dB cutoff frequency of the common-source design is 12 GHz and the cascode feedback amplifier achieves even 17 GHz. At mid-band the common-source and the cascode design achieve a moderate noise figure of 3 dB and 4 dB while maintaining an output power over the complete frequency range of 28 dBm and 29 dBm respectively.
{"title":"Noise degradation of cascodes in broadband power amplifiers","authors":"T. Huber, R. Quay, W. Bösch","doi":"10.1109/INMMIC.2017.7927298","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927298","url":null,"abstract":"This paper compares the noise performance of the common-source and the cascode topology. Although the cascode topology has several advantages over the common-source stage, the noise performance degrades due to the channel noise and the induced gate noise of the common-gate stage. To underline the theory two multi-decade GaN feedback power amplifiers were designed in common-source and cascode topology, using a submicron AlGaN/GaN MMIC technology on SiC substrate. Both designs achieve 13 dB gain and simultaneously good input and output matching. The 3 dB cutoff frequency of the common-source design is 12 GHz and the cascode feedback amplifier achieves even 17 GHz. At mid-band the common-source and the cascode design achieve a moderate noise figure of 3 dB and 4 dB while maintaining an output power over the complete frequency range of 28 dBm and 29 dBm respectively.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129599004","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927297
Lukas Zoscher, Peter Herkess, J. Grosinger, U. Muehlmann, Dominik Amschl, W. Bösch
The usage of threshold voltage (Vth) compensation techniques allows to decrease the input quality factor of RF-DC power converters or more specifically RF charge pumps at low levels of input power, and thus enable the implementation of highly sensitive broadband UHF radiofrequency identification (RFID) transponders (tags). In this work, we present a Vth compensation approach using a combination of gate and bulk biasing for differential charge pump implementations. Prototypes of an eight stage RF charge pump using the proposed Vth compensation technique have been manufactured in a low power 40 nm CMOS technology. Measurements of the test circuits reveal a high power conversion efficiency of 42.7 % and a low input quality factor of approximately 14, at an output power of 4 ßW and a DC voltage level of 1 V. Furthermore, we compare the obtained measurement results with two previously published RF charge pumps.
{"title":"A differential threshold voltage compensated RF-DC power converter for RFID tag ICs","authors":"Lukas Zoscher, Peter Herkess, J. Grosinger, U. Muehlmann, Dominik Amschl, W. Bösch","doi":"10.1109/INMMIC.2017.7927297","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927297","url":null,"abstract":"The usage of threshold voltage (Vth) compensation techniques allows to decrease the input quality factor of RF-DC power converters or more specifically RF charge pumps at low levels of input power, and thus enable the implementation of highly sensitive broadband UHF radiofrequency identification (RFID) transponders (tags). In this work, we present a Vth compensation approach using a combination of gate and bulk biasing for differential charge pump implementations. Prototypes of an eight stage RF charge pump using the proposed Vth compensation technique have been manufactured in a low power 40 nm CMOS technology. Measurements of the test circuits reveal a high power conversion efficiency of 42.7 % and a low input quality factor of approximately 14, at an output power of 4 ßW and a DC voltage level of 1 V. Furthermore, we compare the obtained measurement results with two previously published RF charge pumps.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130896127","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927317
P. Barmuta, F. Ferranti, K. Łukasik, G. P. Gibiino, D. Schreurs
This paper presents a hybrid empirical-behavioral model applied to microwave active devices. The empirical part ensures meaningful, physical response over a wide range of variables, while the behavioral part boosts the accuracy in the particular region of interest. A simple Kriging with zero mean value is employed as the behavioral model. Such hybrid model outperforms the sole empirical model and a hybrid with radial-basis-functions model both in interpolation performance and lower extraction time. The extrapolation capabilities of the model are maintained.
{"title":"Hybrid nonlinear model for microwave active devices using kriging","authors":"P. Barmuta, F. Ferranti, K. Łukasik, G. P. Gibiino, D. Schreurs","doi":"10.1109/INMMIC.2017.7927317","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927317","url":null,"abstract":"This paper presents a hybrid empirical-behavioral model applied to microwave active devices. The empirical part ensures meaningful, physical response over a wide range of variables, while the behavioral part boosts the accuracy in the particular region of interest. A simple Kriging with zero mean value is employed as the behavioral model. Such hybrid model outperforms the sole empirical model and a hybrid with radial-basis-functions model both in interpolation performance and lower extraction time. The extrapolation capabilities of the model are maintained.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126872981","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927316
H. Hamoud, K. El-Akhdar, S. Mons, E. Ngoya
Digital Predistorter (DPD) linearizers are key components for signal integrity and power efficiency in modern communication systems. This article presents a comparative study of the performance of three models for multistandard DPD usage, the Two-Path Memory (TPM) model, the General memory Polynomial (GMP) model, and the Dynamic Deviation Reduction-Based Volterra (DDR) model.
{"title":"Evaluation of an optimal digital predistorter for multistandard systems","authors":"H. Hamoud, K. El-Akhdar, S. Mons, E. Ngoya","doi":"10.1109/INMMIC.2017.7927316","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927316","url":null,"abstract":"Digital Predistorter (DPD) linearizers are key components for signal integrity and power efficiency in modern communication systems. This article presents a comparative study of the performance of three models for multistandard DPD usage, the Two-Path Memory (TPM) model, the General memory Polynomial (GMP) model, and the Dynamic Deviation Reduction-Based Volterra (DDR) model.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128147932","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927308
Karl Freiberger, H. Enzinger, C. Vogel
The error vector magnitude (EVM) is an important system level metric for RF and mixed-signal communication systems and related building blocks. Recently, we have introduced the error power ratio (EPR), a method based on the noise power ratio for estimating the EVM, and presented selected simulation and measurement results. The present paper compares EVM and EPR for many different systems by randomly varying impairment model parameters. To model a multitude of nonlinearities with memory using few parameters, we use a novel baseband Wiener-Hammerstein model with feedback. In 3000 trials of combined phase noise, IQ mismatch and nonlinearity, the mean error (EPR minus EVM) is less than −0.25 dB. Outliers are within −0.5 and −0.8 dB over the entire range of EVM levels (−80 to −15 dB).
误差矢量幅度(EVM)是射频和混合信号通信系统及其相关构件的重要系统级度量。最近，我们介绍了一种基于噪声功率比估计EVM的方法——误差功率比(error power ratio, EPR)，并给出了仿真和测量结果。本文通过随机改变减值模型参数，比较了许多不同系统的EVM和EPR。为了使用少量参数对大量非线性内存进行建模，我们使用了一种新颖的带反馈的基带Wiener-Hammerstein模型。在3000次相位噪声、IQ失配和非线性组合试验中，平均误差(EPR - EVM)小于−0.25 dB。在整个EVM水平范围内(−80至−15 dB)，异常值在−0.5和−0.8 dB之间。
{"title":"The error power ratio estimates EVM for a wide class of impairments: Monte Carlo simulations","authors":"Karl Freiberger, H. Enzinger, C. Vogel","doi":"10.1109/INMMIC.2017.7927308","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927308","url":null,"abstract":"The error vector magnitude (EVM) is an important system level metric for RF and mixed-signal communication systems and related building blocks. Recently, we have introduced the error power ratio (EPR), a method based on the noise power ratio for estimating the EVM, and presented selected simulation and measurement results. The present paper compares EVM and EPR for many different systems by randomly varying impairment model parameters. To model a multitude of nonlinearities with memory using few parameters, we use a novel baseband Wiener-Hammerstein model with feedback. In 3000 trials of combined phase noise, IQ mismatch and nonlinearity, the mean error (EPR minus EVM) is less than −0.25 dB. Outliers are within −0.5 and −0.8 dB over the entire range of EVM levels (−80 to −15 dB).","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125424570","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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