Hybrid fiberoptic-millimeter-wave links

Abstract

he growth of information tcchnolugy demands improvements in communication sys torn capacity, bandwidih (it., spccd), sucurity, mobility, and flcxibil-T ity. Currcntly dcployed communication systems do not offer ihcsc features simultaneously.Fiberoptic technology can provide tremendous bandwidth, but it does not suppork user mobility or flexible system wonfiguration. Wirclcss communication systems using traditional KF or microwave frequencies can providc user mobility, but they do not support high data rates and suciirity (low probability of intcrccpt). Wireless communication systems using millimeter-wave frequencies offer thc potential for broadband, scciirc, wireless communication. Communication security features of millimeter W~V C S include thc ability to spatially control radiated emissions throiigh a combination of the exploitation of high atmospheric attcnuafion and the use of physically small but highly dircctive antennas. Until recently, millimeter-wave technology was extremely cxpcnsivc, but increased commercial invcstment in applications likc local multipoint distribution system (LMDS) have advanced the state-of-the-art of millimotcr-wave components while reducing costs. hdditional cost reductions caii be expected as thcsc commercial technologies gain a grcatcr foothold in the marketplacc.The combined us(! of fiberoptics for point-to-point comniunication and millimctcr waves for short-range wirclcss communication can provide fast data rates, high luvcls of security, arid user mobility simulhneously 111. This article provides a n overview of progress made in [he dcvelopnient of a hybrid 04 " w a v e

Design of an optically frequency or phase‐controlled oscillator for hybrid fiber‐radio LAN at 5.2 GHz

“…The common architecture of the optical part a hybrid fiber radio consists of a digitally modulated microwave subcarrier, which modulates the optical carrier [1]. As the frequency of the subcarrier is usually greater than several GHz, the optical modulation remains difficult, either by direct modulation of a laser current, or by means of an electro-optical modulator.…”

“…In [7], an approximate technique that combines the MoM and the PO method is used for analysis of the finite FSS. Although several studies have investigated some FSSs with of finite extent in one dimension and infinite in the other, using the spectral method to illustrate the edge effect and incident-angle dependencies [1,5], up to now, few papers have treated the finite and curved FSS using rigorous full-wave numerical techniques. The flat-surface FSS is relatively easier to analyze and design; however, its application is limited.…”

“…Due to its important applications in microwave and optical engineering, FSS has attracted the attention of many researchers and several methods have been developed to analyze different types of FSS structures [1][2][3][4][5][6][7]. However, most previous methods focus on the analysis of flat FSS structures of infinite extent.…”

Design and realization of an optically controlled oscillator for radio over fiber at 5.2 GHz

“…The carrier frequency ranges generally from 5 to 60 GHz. Moreoftens, in such radio over fiber systems [1], the signal is modulated on the RF carrier (or sometimes on an IF carrier) at the optical transmitter. This involves difficulties as well for the optical modulation at very high frequencies, requiring complex techniques, as for the transmission on the optical fiber itself (mainly due to dispersion limits).…”

RIN peak suppression for solid state lasers

“…Herczfeld [ 11, Jemison et al [2] have examined the applications of a Nd:LiNb03 mode locked laser in an LMDS system. Because of the good phase noise characteristics the optical generation of the local oscillator signal is feasible.…”