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An impulse-radio ultrawideband (UWB) photonic generation technique based on frequency shifting in the remote connectivity fiber in optical access networks is proposed and analyzed in this paper. This technique is based on optical carrier suppression modulation combined with fiber chromatic dispersion targeting to overcome the bandwidth limitation of optical upconversion, with the advantage of being easily reconfigurable generating simultaneously different RF bands. A comprehensive simulation analysis is performed with special focus on capabilities for dual 24 GHz/60 GHz operation paired with experimental demonstration at 1.24 Gb/s. 60 GHz wireless performance after optical generation and transmission in 12.5 km of standard single-mode fiber is measured demonstrating error-free transmission at 1 m radio distance. The inclusion of remote Gaussian-monocycle pulse shaping is also analyzed in this paper considering dual 24 GHz/60 GHz operation. Pulse-shaped dual 24 GHz/60 GHz generation is experimentally demonstrated at 1.24 Gb/s. Transmission performance is measured at 24 GHz demonstrating error-free transmission. The simulation analysis further indicates that the technique is suitable for UWB generation at higher RF bands such as the W-band (75-110 GHz). Practical implementation considerations and trade-offs (e.g., in terms of cost and number of remote antenna units supported) of this system are also analyzed by simulation showing that the technique is cost effective. [ABSTRACT FROM PUBLISHER]

As large arrays of ultrasensitive cryogenic detectors of radiant energy are developed, multiplexing schemes are required to manage system complexity. Any such scheme must also meet stringent sensitivity, bandwidth, dynamic range and power dissipation specifications. We describe preliminary tests of a microwave frequency-division multiplexed readout of SQUID amplifiers. From these initial tests we estimated the number of SQUIDs that can be multiplexed with this scheme and the sensitivity and bandwidth of each SQUID amplifier. [ABSTRACT FROM AUTHOR]

In this letter, we present a scalable high-speed W-band (75-110-GHz) fiber wireless communication system. By using an optical frequency comb generator, three-channel 8.3-Gb/s/ch optical orthogonal frequency-division-multiplexing (OOFDM) baseband signals in a 15-GHz bandwidth are seamlessly translated from the optical to the wireless domain. The W-band wireless carrier is generated from heterodyne mixing the OOFDM baseband signal with a free-running laser. A W-band electronic down-converter and a digital signal processing-based receiver are used. Three-channel QPSK-OFDM W-band wireless signals are transmitted over 0.5- and 2-m air distance with and without 22.8-km single-mode fiber, respectively, with achieved performance below the forward error correction limit. [ABSTRACT FROM PUBLISHER]

The use of an ultra-wideband (UWB) radio technique is proposed as a viable solution for the distribution of high-definition audio/video content in fiber-to-the-home (FTTH) networks. The approach suitability is demonstrated by the transmission of standards-based UWB signals at 1.25 Gb/s along different FTTH fiber links with 25 km up to 60 km of standard single-mode fiber length in a laboratory experiment. Experimental results suggest that orthogonal frequency-division-multiplexed UWB signals exhibit better transmission performance in FFTH networks than impulse radio UWB signals. [ABSTRACT FROM PUBLISHER]