We are discussing design issues and measurement results for a new type of VCSEL based small form factor low cost optical front end (OFE). The optical interface of the OFE is a duplex LC receptacle. Mechanical, optical and electrical design restrictions are considered. High speed VCSEL biasing, the driver-VCSEL interface, influence of misalignment on RF performance, general requirements for serial 10Gb/s transceivers are main topics. Measurements of transmitter and receiver eye diagrams including a commercially. available driver are presented.

Experimental results of microwave modulation characteristics of high-speed oxide-confined 850 nm VCSELs are presented. First, SFDRs of unpackaged VCSELs measured at various drive currents and frequencies for VCSELs having various oxide apertures are reported, with peak values of approximately 110 dBHz/sup 2/3/. In order to investigate their implementation as low-cost optical sources in analog systems, the fibre length dependence of the SFDR is then measured for a multimode packaged VCSEL. The SFDR remains above 95 dBHz/sup 2/3/ after 800 m of 50 /spl mu/m laser-optimized multimode fibre for both frequencies of 900 and 1800 MHz. This SFDR still fulfills the requirements of analog applications. VCSELs are shown to be insensitive to optical feedback when using absorptive and reflective ball lenses.

Different RF IC technologies are compared regarding their application, frequency range, and suitability for RF and baseband integration. The fully monolithic “phone on a chip” may be technically challenging to realize, and its commercial success may be challenged by progress in multi-chip integration. In the second part, examples of state-of-the-art RF monolithic circuits for applications in the frequency range of 2 to 17 GHz are presented.