Pub Date : 1990-07-23DOI: 10.1109/BAODS.1990.205507
N. Hamilton-Piercy
An evolutionary upgrade of cable television by the introduction of fiber-optic cable and components is discussed. Relatively-long-distance transmission over fiber allows the establishment of many small neighborhood coaxial distribution networks of very high quality and capacity, all served from one hub. Technology available today allows 100000 urban households to be served from a single signal source (primary hub). Intermediate secondary hubs allow individual sections of the community to receive unique programming with subsequent transport on fiber to the 200-home neighborhood. Each neighborhood shares a fiber-optic node, delivering the equivalent of 75 HDTV channels with 50-dB carrier-to-noise ratio and all distortion products suppressed 60 dB or more below the carrier. Analog transmission is assumed to support this number node to the viewer's receiver. Signal formats suitable for direct reception to the home by conventional heterodyne receiver technology is generated at the primary hub, and no further processing is required.<>
{"title":"Role of fiber optics in HDTV","authors":"N. Hamilton-Piercy","doi":"10.1109/BAODS.1990.205507","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205507","url":null,"abstract":"An evolutionary upgrade of cable television by the introduction of fiber-optic cable and components is discussed. Relatively-long-distance transmission over fiber allows the establishment of many small neighborhood coaxial distribution networks of very high quality and capacity, all served from one hub. Technology available today allows 100000 urban households to be served from a single signal source (primary hub). Intermediate secondary hubs allow individual sections of the community to receive unique programming with subsequent transport on fiber to the 200-home neighborhood. Each neighborhood shares a fiber-optic node, delivering the equivalent of 75 HDTV channels with 50-dB carrier-to-noise ratio and all distortion products suppressed 60 dB or more below the carrier. Analog transmission is assumed to support this number node to the viewer's receiver. Signal formats suitable for direct reception to the home by conventional heterodyne receiver technology is generated at the primary hub, and no further processing is required.<<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":"130965979","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.1990.205516
L. Westbrook, N. Fletcher, D. M. Cooper, M. Stevenson, M. Aylett
Measurements are presented which demonstrate that multiple-quantum-well (MQW) lasers can offer significantly lower noise and distortion levels than equivalent double-heterostructure lasers. Improvements of approximately=10 dB in the laser intensity noise and approximately=8 dB in the second-harmonic distortion have been achieved. These figures are close to the predicted improvement of approximately=12 dB expected in MQW lasers as a result of doubling the laser resonant frequency.<>
{"title":"Linearity and noise of InGaAs multi-quantum-well lasers","authors":"L. Westbrook, N. Fletcher, D. M. Cooper, M. Stevenson, M. Aylett","doi":"10.1109/BAODS.1990.205516","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205516","url":null,"abstract":"Measurements are presented which demonstrate that multiple-quantum-well (MQW) lasers can offer significantly lower noise and distortion levels than equivalent double-heterostructure lasers. Improvements of approximately=10 dB in the laser intensity noise and approximately=8 dB in the second-harmonic distortion have been achieved. These figures are close to the predicted improvement of approximately=12 dB expected in MQW lasers as a result of doubling the laser resonant frequency.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"3 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":"115568867","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.1990.205491
H. Yen
Optical interconnects offer several performance advantages for advanced phased-array antennas. New phased-array architecture designs are possible because of the use of photonic technology, which allows the antenna system to be partitioned differently. Functions that can be provided by the optical interconnect include: transmit/receive switch setting, polarization selection, A/D output bus, phase and amplitude control, local oscillator signal distribution, and beam forming or shaping. Some of these functions require digital transmission links, and some require analog microwave links. For the most part the digital links can be implemented using present fiber optic technology. For analog links the insertion loss and signal-to-noise-ratio performance still need to be improved. Nevertheless, fiber optic delay lines have been demonstrated as wideband true time delay microwave phase shifters for antenna beam steering.<>
{"title":"Optical interconnects for phase array antennas","authors":"H. Yen","doi":"10.1109/BAODS.1990.205491","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205491","url":null,"abstract":"Optical interconnects offer several performance advantages for advanced phased-array antennas. New phased-array architecture designs are possible because of the use of photonic technology, which allows the antenna system to be partitioned differently. Functions that can be provided by the optical interconnect include: transmit/receive switch setting, polarization selection, A/D output bus, phase and amplitude control, local oscillator signal distribution, and beam forming or shaping. Some of these functions require digital transmission links, and some require analog microwave links. For the most part the digital links can be implemented using present fiber optic technology. For analog links the insertion loss and signal-to-noise-ratio performance still need to be improved. Nevertheless, fiber optic delay lines have been demonstrated as wideband true time delay microwave phase shifters for antenna beam steering.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"9 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":"115791853","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.1990.205495
M. Tanabe, T. Uno, K. Kaida, H. Nakata, K. Fujito, T. Ichida
The authors investigate the laser diode (LD) over-modulation which causes composite second-order (CSO) distortion and limits the maximum number of loading channels, even if a perfectly linear LD is used. Measured results of CSO are presented as a function of modulation depth for various numbers of channels. The maximum number of channels is found for an ideal LD which has no distortion except the over-modulation area. Using newly developed distributed-feedback (DFB)-LDs for analog transmission, the authors have achieved 64-channel AM-FDM signal transmission of over 8-dB loss, with a fiber launching power of 3 mW, CNR of 51 dB, CSO of less than -60 dBc, and a CTB of less than -65 dBc.<>
{"title":"80ch AM-FDM signals optical transmission","authors":"M. Tanabe, T. Uno, K. Kaida, H. Nakata, K. Fujito, T. Ichida","doi":"10.1109/BAODS.1990.205495","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205495","url":null,"abstract":"The authors investigate the laser diode (LD) over-modulation which causes composite second-order (CSO) distortion and limits the maximum number of loading channels, even if a perfectly linear LD is used. Measured results of CSO are presented as a function of modulation depth for various numbers of channels. The maximum number of channels is found for an ideal LD which has no distortion except the over-modulation area. Using newly developed distributed-feedback (DFB)-LDs for analog transmission, the authors have achieved 64-channel AM-FDM signal transmission of over 8-dB loss, with a fiber launching power of 3 mW, CNR of 51 dB, CSO of less than -60 dBc, and a CTB of less than -65 dBc.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"46 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":"122748702","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 : 1900-01-01DOI: 10.1109/BAODS.1990.205494
J. Lipson, C. J. McGrath
Summary form only given. Analog optical transmission of video signals with distributed feedback lasers is briefly reported. Link quality is determined primarily by the noise and linearity of the laser and is characterized by the carrier-to-noise ratio (CNR), composite second-order distortion (CSO), and composite triple beat (CTB). Measurements were made using multiple continuous wave carriers input to the laser. Among the best results reported are a CNR of 55 dB, a CSO of 65 dBc, and a CTB of 71 dBc for a link loss of 5 dB (12-km fiber) and for 42 channels. End-of-life chip aging data with 16 devices and 3000 h of accelerated aging data with an additional 16 devices reveal a mean time to failure which is conservatively estimated at >25 years. When operated with live video signals, links typically show all improvement of 12 dBc in CTB and 6-12 dBc in CSO. Using a dual pumping configuration of erbium-doped fiber amplifiers (EDFAs), a total output power of 16 mW was achieved.<>
{"title":"Components and systems for AM optical fiber links","authors":"J. Lipson, C. J. McGrath","doi":"10.1109/BAODS.1990.205494","DOIUrl":"https://doi.org/10.1109/BAODS.1990.205494","url":null,"abstract":"Summary form only given. Analog optical transmission of video signals with distributed feedback lasers is briefly reported. Link quality is determined primarily by the noise and linearity of the laser and is characterized by the carrier-to-noise ratio (CNR), composite second-order distortion (CSO), and composite triple beat (CTB). Measurements were made using multiple continuous wave carriers input to the laser. Among the best results reported are a CNR of 55 dB, a CSO of 65 dBc, and a CTB of 71 dBc for a link loss of 5 dB (12-km fiber) and for 42 channels. End-of-life chip aging data with 16 devices and 3000 h of accelerated aging data with an additional 16 devices reveal a mean time to failure which is conservatively estimated at >25 years. When operated with live video signals, links typically show all improvement of 12 dBc in CTB and 6-12 dBc in CSO. Using a dual pumping configuration of erbium-doped fiber amplifiers (EDFAs), a total output power of 16 mW was achieved.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115627269","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 : 1900-01-01DOI: 10.1109/baods.1990.205501
G. Betts, C. Cox, K. Ray
An optical analog link operating at 20 GHz with a 3-dB bandwidth of 5.2 GHz was demonstrated. This link has an intermodulation-free dynamic range of 108 dB-Hz/sup 2/3/ and a maximum signal-to-noise ratio (SNR) of 155 dB-Hz. Previously reported direct modulation analog links have not been able to operate at 20 GHz and, even in the 10-GHz frequency range, have had 20-30-dB-poorer SNRs; externally modulated links are capable of high-frequency operation but have demonstrated 30-50-dB-poorer SNRs than the present link. The link consists of a CW laser, an integrated-optical intensity modulator, and a p-i-n diode detector connected by fibers; it contains no amplifiers. The link performance is evaluated at the RF ports, i.e. it is treated as a two-port RF device. It is noted that by simply using a detector with no rolloff and by reducing the modulator excess optical insertion loss to 3 dB, the RF insertion loss can be improved to -25 dB and the noise figure to 33 dB.<>
{"title":"20-GHz optical analog link using an external modulator","authors":"G. Betts, C. Cox, K. Ray","doi":"10.1109/baods.1990.205501","DOIUrl":"https://doi.org/10.1109/baods.1990.205501","url":null,"abstract":"An optical analog link operating at 20 GHz with a 3-dB bandwidth of 5.2 GHz was demonstrated. This link has an intermodulation-free dynamic range of 108 dB-Hz/sup 2/3/ and a maximum signal-to-noise ratio (SNR) of 155 dB-Hz. Previously reported direct modulation analog links have not been able to operate at 20 GHz and, even in the 10-GHz frequency range, have had 20-30-dB-poorer SNRs; externally modulated links are capable of high-frequency operation but have demonstrated 30-50-dB-poorer SNRs than the present link. The link consists of a CW laser, an integrated-optical intensity modulator, and a p-i-n diode detector connected by fibers; it contains no amplifiers. The link performance is evaluated at the RF ports, i.e. it is treated as a two-port RF device. It is noted that by simply using a detector with no rolloff and by reducing the modulator excess optical insertion loss to 3 dB, the RF insertion loss can be improved to -25 dB and the noise figure to 33 dB.<<ETX>>","PeriodicalId":119716,"journal":{"name":"LEOS Summer Topical on Broadband Analog Optoelectronics: Devices and Systems","volume":"337 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123339997","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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