Kenneth R. Demarest

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—The performance of high-speed digital fiber-optic transmission using subcarrier multiplexing (SCM) is investigated both analytically and numerically. In order to reduce the impact of fiber chromatic dispersion and increase bandwidth efficiency, optical single-sideband (OSSB) modulation was used. Because frequency spacing between adjacent subcarriers can be(More)
— A new phase-matching factor is derived for four-wave mixing (FWM) that includes the effects of self-phase and cross-phase modulation in optical fibers. Theoretical results predict that the wavelength of peak FWM efficiency shifts away from the fiber zero-dispersion wavelength and indicate that the conventional phase-matching factor may induce significant(More)
— The spectral characteristics of cross-phase modulation (XPM) in multispan intensity-modulation direct-detection (IM-DD) optical systems are investigated, both experimentally and theoretically. XPM crosstalk levels and its spectral features are found to be strongly dependent on fiber dispersion and optical signal channel spacing. Interference between(More)
—An adaptive polarization-mode dispersion (PMD) compensation system has been developed to cancel the effects of first-order PMD by producing a complementary PMD vector in the receiver. Control parameters for the PMD compensation system comprised of a polarization controller and a PMD emu-lator are derived from the nonreturn-to-zero (NRZ) signal in the(More)
—The T-match structure is commonly used to match an RFID chip's reactive impedance to a dipole. Models that describe T-match are known, but they are neither sufficiently accurate to model antennas nor to synthesize the antenna geometry. Here, we present the embedded T-match circuit model, which is amenable to accurate analysis and synthesis.
— The spectral characteristics of cross-phase modulation (XPM) in multispan intensity-modulation direct-detection optical systems were investigated both experimentally and theoretically. XPM crosstalk levels and its spectral features were found to be strongly dependent on fiber dispersion and optical signal channel spacing. Interference between XPM-induced(More)
A 10Gb/s SCM long-haul optical system is reported. 4 x 2.5Gb/s data streams are combined into one wavelength, which occupies a 20GHz optical bandwidth. Optical SSB is used to increase bandwidth efficiency and reduce dispersion penalty. In order to use the optical bandwidth provided by optical fibers more efficiently, new transmission technologies have been(More)
—Subcarrier multiplexing (SCM) optical systems with high subcarrier frequencies are susceptible to power fading caused by fiber polarization-mode dispersion (PMD). In this letter, an SCM optical receiver free of carrier fading is proposed and demonstrated using polarization diversity. Unlike conventional PMD compensators, this setup does not require a(More)
—A novel and simple method to generate a variable-rate, ultrahigh-speed optical pulse train is demonstrated using a dual-wavelength, strongly gain-coupled distributed-feedback laser diode. The repetition rate of the optical pulse train is continuously tunable from 25 to 80 GHz and no high-speed electronics are required in this method. G ENERATING(More)