The Experts below are selected from a list of 20829 Experts worldwide ranked by ideXlab platform
Marius Florin Niculescu - One of the best experts on this subject based on the ideXlab platform.
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the double edged sword of backward compatibility the adoption of multigenerational platforms in the presence of intergenerational services
Information Systems Research, 2016Co-Authors: Ilhorn Hann, Byungwan Koh, Marius Florin NiculescuAbstract:We investigate the impact of the intergenerational nature of services, via backward compatibility, on the adoption of multigenerational platforms. We consider a mobile Internet platform that has evolved over several generations and for which users download complementary services from third-party providers. These services are often intergenerational: newer platform generations are backward compatible with respect to services released under earlier generation platforms. In this paper, we propose a model to identify the main drivers of consumers’ choice of platform generation, accounting for (i) the migration from older to newer platform generations, (ii) the indirect network effect on platform adoption due to same-generation services, and (iii) the effect on platform adoption due to the consumption of intergenerational services via backward compatibility. Using data on mobile Internet platform adoption and services consumption for the time period of 2001–2007 from a major Wireless Carrier in an Asian countr...
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the double edged sword of backward compatibility the adoption of multi generational platforms in the presence of intergenerational services
Social Science Research Network, 2016Co-Authors: Ilhorn Hann, Byungwan Koh, Marius Florin NiculescuAbstract:We investigate the impact of the intergenerational nature of services, via backward compatibility, on the adoption of multi-generational platforms. We consider a mobile Internet platform that has evolved over several generations and for which users download complementary services from third party providers. These services are often intergenerational: newer platform generations are backward compatible with respect to services released under earlier generation platforms. In this paper, we propose a model to identify the main drivers of consumers’ choice of platform generation, accounting for (i) the migration from older to newer platform generations, (ii) the indirect network effect on platform adoption due to same-generation services, and (iii) the effect on platform adoption due to the consumption of intergenerational services via backward compatibility. Using data on mobile Internet platform adoption and services consumption for the time period of 2001-2007 from a major Wireless Carrier in an Asian country, we estimate the three effects noted above. We show that both the migration from older to newer platform generations and the indirect network effects are significant. The surprising finding is that intergenerational services that connect subsequent generations of platforms essentially engender backward compatibility with two opposing effects. While an intergenerational service may accelerate the migration to the subsequent platform generations, it may also, perhaps unintentionally, provide a fresh lease on life for earlier generation platforms due to the continued use of earlier generation services on newer platform generations.
Geekung Chang - One of the best experts on this subject based on the ideXlab platform.
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adaptive digitization and variable channel coding for enhancement of compressed digital mobile fronthaul in pam 4 optical links
Journal of Lightwave Technology, 2017Co-Authors: Feng Lu, Mu Xu, Lin Cheng, Jing Wang, Shuyi Shen, Hyung Joon Cho, Geekung ChangAbstract:The standardization and development of LTE-A and 5G introduced advanced Wireless technologies including multiple-input multiple-output and Carrier aggregation, which require multiple Wireless Carriers to be delivered to and from each remote radio head. The common public radio interface (CPRI) as the mainstream standard in mobile fronthaul (MFH) with on-off-keying-based optical links cannot fulfill the capacity and efficiency requirement. Instead, using compressed CPRI in a high-speed pulse-amplitude-modulation-4 (PAM-4) link is actively researched and demonstrated. In this paper, we propose and demonstrate adaptive digitization and channel coding based on these compression and capacity boosting technologies. Depending on the optical link condition, the digitization bits and channel coding rates can be adaptively and dynamically changed to achieve the lowest error vector magnitude (EVM) of Wireless Carriers. By separating digitization bits into high bits and low bits, the coding overhead can be different between groups, while still keeping the same bit rate per Wireless Carrier. Based on the existing digital MFH infrastructure, the proposed scheme can significantly improve the capacity and sensitivity in the PAM-4-based compressed digital MFH. Capacity gains from 30% to 68%, sensitivity improvement of 2–9 dB, and significant EVM improvements are demonstrated experimentally, comparing with other compressed CPRI MFH solutions.
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multichannel 120 gb s data transmission over 2 times 2 mimo fiber Wireless link at w band
IEEE Photonics Technology Letters, 2013Co-Authors: Junwen Zhang, Jianjun Yu, Ze Dong, Xinying Li, Geekung ChangAbstract:We experimentally demonstrated a seamlessly integrated fiber-Wireless system that delivers multichannel 120-Gb/s data through 80-km fiber and 2-m 2×2 multiple-input multiple-output (MIMO) Wireless link at 92-GHz W-band adopting polarization division multiplexing quadrature phase shift keying (PDM-QPSK) modulation. The three-channel 3×40-Gb/s optical PDM-QPSK signals with 12.5-GHz channel spacing are simultaneously upconverted to 92-GHz Wireless Carrier by optical polarization-diversity heterodyne beating and then transmitted and received by two pairs of transmitter and receiver antennas, which form a full 2×2 MIMO Wireless link. At the Wireless receiver, a two-stage analog and digital downconversion is performed. Polarization and Wireless 2×2 MIMO demultiplexing are realized by constant modulus algorithm based on digital signal processing. The bit-error ratio performance for the 120-Gb/s PDM-QPSK signal is measured after 80-km single-mode fiber-28 and 2-m Wireless transmission.
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fiber Wireless transmission system of 108 gb sdata over 80 km fiber and 2 2multiple input multiple output Wireless links at 100 ghz w band frequency
Optics Letters, 2012Co-Authors: Xinying Li, Ze Dong, Jianjun Yu, Yufeng Shao, Geekung ChangAbstract:We experimentally demonstrate a seamlessly integrated fiber-Wireless system that delivers a 108 Gb/s signal through 80 km fiber and 1 m Wireless transport over free space at 100 GHz adopting polarization-division-multiplexing quadrature-phase-shift-keying (PDM-QPSK) modulation and heterodyning coherent detection. The X- and Y-polarization components of the optical PDM-QPSK baseband signal are simultaneously upconverted to 100 GHz Wireless Carrier by optical polarization-diversity heterodyne beating, and then independently transmitted and received by two pairs of transmitter and receiver antennas, which form a 2×2 multiple-input multiple-output Wireless link. At the Wireless receiver, two-stage downconversion is performed firstly in the analog domain based on balanced mixer and sinusoidal radio frequency signal, and then in the digital domain based on digital signal processing (DSP). Polarization demultiplexing is realized by the constant modulus algorithm in the DSP part at the receiver. The bit-error ratio for the 108 Gb/s PDM-QPSK signal is less than the pre-forward-error-correction threshold of 3.8×10−3 after both 1 m Wireless delivery at 100 GHz and 80 km single-mode fiber-28 transmission. To our knowledge, this is the first demonstration to realize 100 Gb/s signal delivery through both fiber and Wireless links at 100 GHz.
Ilhorn Hann - One of the best experts on this subject based on the ideXlab platform.
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the double edged sword of backward compatibility the adoption of multigenerational platforms in the presence of intergenerational services
Information Systems Research, 2016Co-Authors: Ilhorn Hann, Byungwan Koh, Marius Florin NiculescuAbstract:We investigate the impact of the intergenerational nature of services, via backward compatibility, on the adoption of multigenerational platforms. We consider a mobile Internet platform that has evolved over several generations and for which users download complementary services from third-party providers. These services are often intergenerational: newer platform generations are backward compatible with respect to services released under earlier generation platforms. In this paper, we propose a model to identify the main drivers of consumers’ choice of platform generation, accounting for (i) the migration from older to newer platform generations, (ii) the indirect network effect on platform adoption due to same-generation services, and (iii) the effect on platform adoption due to the consumption of intergenerational services via backward compatibility. Using data on mobile Internet platform adoption and services consumption for the time period of 2001–2007 from a major Wireless Carrier in an Asian countr...
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the double edged sword of backward compatibility the adoption of multi generational platforms in the presence of intergenerational services
Social Science Research Network, 2016Co-Authors: Ilhorn Hann, Byungwan Koh, Marius Florin NiculescuAbstract:We investigate the impact of the intergenerational nature of services, via backward compatibility, on the adoption of multi-generational platforms. We consider a mobile Internet platform that has evolved over several generations and for which users download complementary services from third party providers. These services are often intergenerational: newer platform generations are backward compatible with respect to services released under earlier generation platforms. In this paper, we propose a model to identify the main drivers of consumers’ choice of platform generation, accounting for (i) the migration from older to newer platform generations, (ii) the indirect network effect on platform adoption due to same-generation services, and (iii) the effect on platform adoption due to the consumption of intergenerational services via backward compatibility. Using data on mobile Internet platform adoption and services consumption for the time period of 2001-2007 from a major Wireless Carrier in an Asian country, we estimate the three effects noted above. We show that both the migration from older to newer platform generations and the indirect network effects are significant. The surprising finding is that intergenerational services that connect subsequent generations of platforms essentially engender backward compatibility with two opposing effects. While an intergenerational service may accelerate the migration to the subsequent platform generations, it may also, perhaps unintentionally, provide a fresh lease on life for earlier generation platforms due to the continued use of earlier generation services on newer platform generations.
Byungwan Koh - One of the best experts on this subject based on the ideXlab platform.
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the double edged sword of backward compatibility the adoption of multigenerational platforms in the presence of intergenerational services
Information Systems Research, 2016Co-Authors: Ilhorn Hann, Byungwan Koh, Marius Florin NiculescuAbstract:We investigate the impact of the intergenerational nature of services, via backward compatibility, on the adoption of multigenerational platforms. We consider a mobile Internet platform that has evolved over several generations and for which users download complementary services from third-party providers. These services are often intergenerational: newer platform generations are backward compatible with respect to services released under earlier generation platforms. In this paper, we propose a model to identify the main drivers of consumers’ choice of platform generation, accounting for (i) the migration from older to newer platform generations, (ii) the indirect network effect on platform adoption due to same-generation services, and (iii) the effect on platform adoption due to the consumption of intergenerational services via backward compatibility. Using data on mobile Internet platform adoption and services consumption for the time period of 2001–2007 from a major Wireless Carrier in an Asian countr...
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the double edged sword of backward compatibility the adoption of multi generational platforms in the presence of intergenerational services
Social Science Research Network, 2016Co-Authors: Ilhorn Hann, Byungwan Koh, Marius Florin NiculescuAbstract:We investigate the impact of the intergenerational nature of services, via backward compatibility, on the adoption of multi-generational platforms. We consider a mobile Internet platform that has evolved over several generations and for which users download complementary services from third party providers. These services are often intergenerational: newer platform generations are backward compatible with respect to services released under earlier generation platforms. In this paper, we propose a model to identify the main drivers of consumers’ choice of platform generation, accounting for (i) the migration from older to newer platform generations, (ii) the indirect network effect on platform adoption due to same-generation services, and (iii) the effect on platform adoption due to the consumption of intergenerational services via backward compatibility. Using data on mobile Internet platform adoption and services consumption for the time period of 2001-2007 from a major Wireless Carrier in an Asian country, we estimate the three effects noted above. We show that both the migration from older to newer platform generations and the indirect network effects are significant. The surprising finding is that intergenerational services that connect subsequent generations of platforms essentially engender backward compatibility with two opposing effects. While an intergenerational service may accelerate the migration to the subsequent platform generations, it may also, perhaps unintentionally, provide a fresh lease on life for earlier generation platforms due to the continued use of earlier generation services on newer platform generations.
Xinying Li - One of the best experts on this subject based on the ideXlab platform.
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multichannel 120 gb s data transmission over 2 times 2 mimo fiber Wireless link at w band
IEEE Photonics Technology Letters, 2013Co-Authors: Junwen Zhang, Jianjun Yu, Ze Dong, Xinying Li, Geekung ChangAbstract:We experimentally demonstrated a seamlessly integrated fiber-Wireless system that delivers multichannel 120-Gb/s data through 80-km fiber and 2-m 2×2 multiple-input multiple-output (MIMO) Wireless link at 92-GHz W-band adopting polarization division multiplexing quadrature phase shift keying (PDM-QPSK) modulation. The three-channel 3×40-Gb/s optical PDM-QPSK signals with 12.5-GHz channel spacing are simultaneously upconverted to 92-GHz Wireless Carrier by optical polarization-diversity heterodyne beating and then transmitted and received by two pairs of transmitter and receiver antennas, which form a full 2×2 MIMO Wireless link. At the Wireless receiver, a two-stage analog and digital downconversion is performed. Polarization and Wireless 2×2 MIMO demultiplexing are realized by constant modulus algorithm based on digital signal processing. The bit-error ratio performance for the 120-Gb/s PDM-QPSK signal is measured after 80-km single-mode fiber-28 and 2-m Wireless transmission.
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fiber Wireless transmission system of 108 gb sdata over 80 km fiber and 2 2multiple input multiple output Wireless links at 100 ghz w band frequency
Optics Letters, 2012Co-Authors: Xinying Li, Ze Dong, Jianjun Yu, Yufeng Shao, Geekung ChangAbstract:We experimentally demonstrate a seamlessly integrated fiber-Wireless system that delivers a 108 Gb/s signal through 80 km fiber and 1 m Wireless transport over free space at 100 GHz adopting polarization-division-multiplexing quadrature-phase-shift-keying (PDM-QPSK) modulation and heterodyning coherent detection. The X- and Y-polarization components of the optical PDM-QPSK baseband signal are simultaneously upconverted to 100 GHz Wireless Carrier by optical polarization-diversity heterodyne beating, and then independently transmitted and received by two pairs of transmitter and receiver antennas, which form a 2×2 multiple-input multiple-output Wireless link. At the Wireless receiver, two-stage downconversion is performed firstly in the analog domain based on balanced mixer and sinusoidal radio frequency signal, and then in the digital domain based on digital signal processing (DSP). Polarization demultiplexing is realized by the constant modulus algorithm in the DSP part at the receiver. The bit-error ratio for the 108 Gb/s PDM-QPSK signal is less than the pre-forward-error-correction threshold of 3.8×10−3 after both 1 m Wireless delivery at 100 GHz and 80 km single-mode fiber-28 transmission. To our knowledge, this is the first demonstration to realize 100 Gb/s signal delivery through both fiber and Wireless links at 100 GHz.
