Pub Date : 1990-07-23DOI: 10.1109/BAODS.1990.205509
C. Lo, L. Reith, G. Coquin, H. Tohme
Subcarrier-multiplexed (SCM) lightwave systems for near-term, potentially low-cost video distribution are considered. An experiment is reported in which a single wavelength, carrying simultaneously 622-Mb/s data, ten C-band satellite channels between 950 and 1450 MHz, and three HDTV signals from 1.5 to 2.1 GHz, via amplification by a packaged traveling-wave laser amplifier (TWLA) was transmitted through 10 km of a single-mode (SM) fiber and split 128 ways optically. No optical filter was used after the amplifier. At the receiver, with a 3-dB power margin, the data bit error rate (BER) was 10/sup -9/ and carrier-to-noise ratios (CNRs) of 16.9 dB and 12.9 dB, respectively, were measured for the HDTV and satellite signals. The effects of TWLA-introduced noise degradations on BER and CNR at various input power levels to the TWLA are also quantified.<>
{"title":"Distribution of 3 FM-HDTV and 10 satellite FM-NTSC signals and 622 Mb/s data over 10 km of fiber to 128 customers using a packaged traveling-wave laser amplifier","authors":"C. Lo, L. Reith, G. Coquin, H. Tohme","doi":"10.1109/BAODS.1990.205509","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205509","url":null,"abstract":"Subcarrier-multiplexed (SCM) lightwave systems for near-term, potentially low-cost video distribution are considered. An experiment is reported in which a single wavelength, carrying simultaneously 622-Mb/s data, ten C-band satellite channels between 950 and 1450 MHz, and three HDTV signals from 1.5 to 2.1 GHz, via amplification by a packaged traveling-wave laser amplifier (TWLA) was transmitted through 10 km of a single-mode (SM) fiber and split 128 ways optically. No optical filter was used after the amplifier. At the receiver, with a 3-dB power margin, the data bit error rate (BER) was 10/sup -9/ and carrier-to-noise ratios (CNRs) of 16.9 dB and 12.9 dB, respectively, were measured for the HDTV and satellite signals. The effects of TWLA-introduced noise degradations on BER and CNR at various input power levels to the TWLA are also quantified.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121339230","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205493
C. Cox, G. Betts, A. Yee
Operation of a broadband, incrementally lossless, fiber-optic link is reported. By using a solid-state laser as the CW source, a dynamic range for this externally modulated link was measured and shown to exceed that of a directly modulated link. The modulator was a conventional Mach-Zehnder design. The average optical power on the detector was 20 mW. The modulator input and detector output are resistively terminated with 50 Omega , and the link RF-to-RF insertion loss vs. frequency is measured using an RF network analyzer. The maximum intermodulation-free (IM-free) dynamic range occurs at the optical modulation depth (OMD) for which the output intermodulation power equals the link output noise power. Consequently, the maximum IM-free dynamic range depends not only on the linearity of the modulating device, but also on the sources of noise in the link.<>
{"title":"Incrementally lossless, broad-bandwidth analog fiber-optic link","authors":"C. Cox, G. Betts, A. Yee","doi":"10.1109/BAODS.1990.205493","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205493","url":null,"abstract":"Operation of a broadband, incrementally lossless, fiber-optic link is reported. By using a solid-state laser as the CW source, a dynamic range for this externally modulated link was measured and shown to exceed that of a directly modulated link. The modulator was a conventional Mach-Zehnder design. The average optical power on the detector was 20 mW. The modulator input and detector output are resistively terminated with 50 Omega , and the link RF-to-RF insertion loss vs. frequency is measured using an RF network analyzer. The maximum intermodulation-free (IM-free) dynamic range occurs at the optical modulation depth (OMD) for which the output intermodulation power equals the link output noise power. Consequently, the maximum IM-free dynamic range depends not only on the linearity of the modulating device, but also on the sources of noise in the link.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129839186","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205510
R. Gross, G. Joyce, W. Rideout, R. Olshansky
Coherent subcarrier multiplexed (SCM) systems for broadband fiber-optic video distribution networks are considered. A specific architecture is discussed enabling both the transmitter and local oscillator (LO) laser to be shared among multiple optoelectronic receivers. It is shown that the system performance can be greatly enhanced by inserting an inline optical amplifier. A consequence of this system architecture is that the shared LO cannot be used for optical tuning. However, this design can be employed for video distribution in a fiber-to-the-curb architecture or as a video feeder network connecting the central office to multiple distribution hubs, where optical tuning is not an issue. Measurements with an optical amplifier demonstrated transmission of 48 FM-channels with the LO being shared among eight subscribers. The analysis of the coherent SCM system showed that a significant increase in the number of subscribers can be obtained when an inline optical amplifier is used.<>
{"title":"Coherent optical video distribution system using shared local oscillator configuration","authors":"R. Gross, G. Joyce, W. Rideout, R. Olshansky","doi":"10.1109/BAODS.1990.205510","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205510","url":null,"abstract":"Coherent subcarrier multiplexed (SCM) systems for broadband fiber-optic video distribution networks are considered. A specific architecture is discussed enabling both the transmitter and local oscillator (LO) laser to be shared among multiple optoelectronic receivers. It is shown that the system performance can be greatly enhanced by inserting an inline optical amplifier. A consequence of this system architecture is that the shared LO cannot be used for optical tuning. However, this design can be employed for video distribution in a fiber-to-the-curb architecture or as a video feeder network connecting the central office to multiple distribution hubs, where optical tuning is not an issue. Measurements with an optical amplifier demonstrated transmission of 48 FM-channels with the LO being shared among eight subscribers. The analysis of the coherent SCM system showed that a significant increase in the number of subscribers can be obtained when an inline optical amplifier is used.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128164776","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205512
L. A. Campos, E. E. Ames
Experimental and theoretical results are reported for fiber-optic links using MESFETs as light detectors for application in monolithic microwave integrated circuit (MMIC)-based phased-array antennas. Since MESFETs are compatible with MMICs, it is easy to implement a MESFET receiver in MMIC transmit-and-receive (T/R) modules. A receiver design using MESFET detection is less complicated and occupies less area than a PINFET receiver. The use of single-mode (SM) and multimode graded-index (MMGI) fiber to illuminate microwave devices is examined. The keys to this investigation are the high responsivity (R) values obtained by illuminating MESFETS with fibers (R/sub SM/=1.87 mA/mW; R/sub MMGI/=1.18 mA/mW) and the phase coherency demonstration of MESFET fiber-optic links at microwave frequencies using an antenna array and measuring its radiation pattern RF link loss improvements of 9 to 13 dB with respect to links using p-i-n photodiodes were measured.<>
{"title":"Fibre-optic illumination of GaAs MESFETs for use in phased-array antennas","authors":"L. A. Campos, E. E. Ames","doi":"10.1109/BAODS.1990.205512","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205512","url":null,"abstract":"Experimental and theoretical results are reported for fiber-optic links using MESFETs as light detectors for application in monolithic microwave integrated circuit (MMIC)-based phased-array antennas. Since MESFETs are compatible with MMICs, it is easy to implement a MESFET receiver in MMIC transmit-and-receive (T/R) modules. A receiver design using MESFET detection is less complicated and occupies less area than a PINFET receiver. The use of single-mode (SM) and multimode graded-index (MMGI) fiber to illuminate microwave devices is examined. The keys to this investigation are the high responsivity (R) values obtained by illuminating MESFETS with fibers (R/sub SM/=1.87 mA/mW; R/sub MMGI/=1.18 mA/mW) and the phase coherency demonstration of MESFET fiber-optic links at microwave frequencies using an antenna array and measuring its radiation pattern RF link loss improvements of 9 to 13 dB with respect to links using p-i-n photodiodes were measured.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115721086","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205498
T. Uno, M. Tanabe, Y. Matsui, M. Ohshima, K. Fujito
The distortion mechanism of distributed-feedback (DFB) laser modules has not yet been studied extensively. The authors report an additional distortion degradation characteristic, which is caused by the etalon interference effect in a laser module. This effect occurs between two or more reflection facets of the optical components in a module, such as optical lens, polarizers, Faraday crystal, and fiber facet. The calculation results for the second-harmonic distortions (HM2) show that less than 0.1% power reflection from both etalon facets can degrade HM2 up to 50 dB in certain conditions. It is notable that HM2 and HM3 values change periodically against the center wavelength change, and that HM2 and HM3 take two peaks in the free spectral range (FSR) of the etalon cavity.<>
{"title":"High quality 64 channel 15 km AM-FDM transmission using low distortion characteristics DFB laser module","authors":"T. Uno, M. Tanabe, Y. Matsui, M. Ohshima, K. Fujito","doi":"10.1109/BAODS.1990.205498","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205498","url":null,"abstract":"The distortion mechanism of distributed-feedback (DFB) laser modules has not yet been studied extensively. The authors report an additional distortion degradation characteristic, which is caused by the etalon interference effect in a laser module. This effect occurs between two or more reflection facets of the optical components in a module, such as optical lens, polarizers, Faraday crystal, and fiber facet. The calculation results for the second-harmonic distortions (HM2) show that less than 0.1% power reflection from both etalon facets can degrade HM2 up to 50 dB in certain conditions. It is notable that HM2 and HM3 values change periodically against the center wavelength change, and that HM2 and HM3 take two peaks in the free spectral range (FSR) of the etalon cavity.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123816705","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205511
V. Shukla, R. Kearns, L. Ulbricht
A number of interdependent electrical and optical parameters (viz., frequency deviation, optical modulation depth, frequency plan, laser relative intensity noise (RIN), and receiver sensitivity) were investigated analytically and experimentally to determine possible tradeoffs in optimizing system performance for an 80-channel supertrunk application requiring a more demanding 60-dB SNR and a system gain exceeding 15 dB. An analytical model developed to examine the cumulative effects of various parameters on system gain is discussed. Possible frequency band dependence was examined experimentally on an 80-channel FM subcarrier multiplexing (FM-SCM) system set up with a notch filter in the test channel to isolate the effects of the optoelectronic components.<>
{"title":"Opportunities for optimizing interdependent FM-SCM system parameters for high capacity, high performance video supertrunks","authors":"V. Shukla, R. Kearns, L. Ulbricht","doi":"10.1109/BAODS.1990.205511","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205511","url":null,"abstract":"A number of interdependent electrical and optical parameters (viz., frequency deviation, optical modulation depth, frequency plan, laser relative intensity noise (RIN), and receiver sensitivity) were investigated analytically and experimentally to determine possible tradeoffs in optimizing system performance for an 80-channel supertrunk application requiring a more demanding 60-dB SNR and a system gain exceeding 15 dB. An analytical model developed to examine the cumulative effects of various parameters on system gain is discussed. Possible frequency band dependence was examined experimentally on an 80-channel FM subcarrier multiplexing (FM-SCM) system set up with a notch filter in the test channel to isolate the effects of the optoelectronic components.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128330617","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205502
C. Bulmer, W. Burns, C. Pickett
The characteristics are presented of a 1*2 coupler with coplanar stripline, traveling-wave electrodes designed for broadband operation to approximately 10 GHz. Modulators are fabricated by Ti diffusion in Z-cut, Y-propagating LiNbO/sub 3/ to form single-mode guides at the 1.3- mu m wavelength. Electrodes are defined over an approximately 0.3- mu m-thick SiO/sub 2/ buffer layer in approximately 3- mu m electroplated gold, with L=6.5 mm. The waveguide parameters and arm separation are designed with the aim of achieving coupling coefficients corresponding to 0.5>
{"title":"Linear, 1*2 directional coupler modulator with 10 GHz bandwidth","authors":"C. Bulmer, W. Burns, C. Pickett","doi":"10.1109/BAODS.1990.205502","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205502","url":null,"abstract":"The characteristics are presented of a 1*2 coupler with coplanar stripline, traveling-wave electrodes designed for broadband operation to approximately 10 GHz. Modulators are fabricated by Ti diffusion in Z-cut, Y-propagating LiNbO/sub 3/ to form single-mode guides at the 1.3- mu m wavelength. Electrodes are defined over an approximately 0.3- mu m-thick SiO/sub 2/ buffer layer in approximately 3- mu m electroplated gold, with L=6.5 mm. The waveguide parameters and arm separation are designed with the aim of achieving coupling coefficients corresponding to 0.5<or=y<or=1.0. which gives optimum sensitivity. Measurements were made of the modulation characteristics at 1 kHz. The results indicate that a good linear modulation performance can be achieved with a 1*2 directional coupler having a 10-11-GHz bandwidth response.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121866571","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205505
R. Snelling
The deployment of fiber optic technology is reviewed. Cost trends for fiber vs copper, better transmission quality, and a reduction in fiber maintenance expense are pointed out as the major reasons for using fiber optic technology. The fact that the fiber optic facilities, which are the most economical and efficient means of providing existing telephone service, also possess the capability of transporting video signals is naturally an additional reason supporting their use.<>
{"title":"Telecommunications industry rationale for fibre-optics-a business perspective","authors":"R. Snelling","doi":"10.1109/BAODS.1990.205505","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205505","url":null,"abstract":"The deployment of fiber optic technology is reviewed. Cost trends for fiber vs copper, better transmission quality, and a reduction in fiber maintenance expense are pointed out as the major reasons for using fiber optic technology. The fact that the fiber optic facilities, which are the most economical and efficient means of providing existing telephone service, also possess the capability of transporting video signals is naturally an additional reason supporting their use.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127759753","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205508
W. Way, C. Lin
Applications of both semiconductor optical amplifiers, (SOAs) and erbium-doped fiber amplifiers (EDFAs) in broadband distribution systems are discussed. Advantages and disadvantages of both types of amplifier are addressed. The discussion is concentrated on the applications of power and inline amplifiers. In addition, wavelength-division-multiplexing (WDM) and optical-frequency-division-multiplexing (OFDM) technologies, in combination with optical amplifiers are shown to provide a significant increase in the broadband system capacity and flexibility.<>
{"title":"Optical amplifiers in broadband distribution systems","authors":"W. Way, C. Lin","doi":"10.1109/BAODS.1990.205508","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205508","url":null,"abstract":"Applications of both semiconductor optical amplifiers, (SOAs) and erbium-doped fiber amplifiers (EDFAs) in broadband distribution systems are discussed. Advantages and disadvantages of both types of amplifier are addressed. The discussion is concentrated on the applications of power and inline amplifiers. In addition, wavelength-division-multiplexing (WDM) and optical-frequency-division-multiplexing (OFDM) technologies, in combination with optical amplifiers are shown to provide a significant increase in the broadband system capacity and flexibility.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124193740","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 : 1990-07-23DOI: 10.1109/BAODS.1990.205513
G. Simonis, K. Purchase, R. Hay, F. Adams, E. Cheng, T. Kane
The monolithic diode-laser-pumped unidirectional single-mode Nd:YAG ring laser has extraordinary properties of coherence and frequency stability. Reported is the use of a pair of such lasers voltage controlled by a PC-AT computer to frequency scan the laser frequency and the heterodyne frequency between the lasers in an automated fashion. An IEEE-488 bus interface to an HP8566B spectrum analyser is used to provide computerized data acquisition of heterodyne frequency (and, thereby, change in tuned laser frequency) and heterodyne power. This automated heterodyne instrumentation has been applied in a straightforward fashion to the characterization of the absolute frequency response of individual infrared detectors over the DC-to-24-GHz calibrated power range of the spectrum analyzer.<>
{"title":"Automated laser heterodyne optical/microwave spectrum analyzer","authors":"G. Simonis, K. Purchase, R. Hay, F. Adams, E. Cheng, T. Kane","doi":"10.1109/BAODS.1990.205513","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205513","url":null,"abstract":"The monolithic diode-laser-pumped unidirectional single-mode Nd:YAG ring laser has extraordinary properties of coherence and frequency stability. Reported is the use of a pair of such lasers voltage controlled by a PC-AT computer to frequency scan the laser frequency and the heterodyne frequency between the lasers in an automated fashion. An IEEE-488 bus interface to an HP8566B spectrum analyser is used to provide computerized data acquisition of heterodyne frequency (and, thereby, change in tuned laser frequency) and heterodyne power. This automated heterodyne instrumentation has been applied in a straightforward fashion to the characterization of the absolute frequency response of individual infrared detectors over the DC-to-24-GHz calibrated power range of the spectrum analyzer.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122186327","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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