Abstract

The use of optical fiber for efficient transport of narrowband millimeter-wave (>30 GHz) signals in mm-wave wireless picocellular networks and fiber-fed phased-array antenna systems has recently gained considerable attention.^1,2 Because these systems may deploy a large number of antennas, the use of a mm-wave fiber infrastructure rests primarily upon the availability of low-cost mm-wave optical transmitters. The technique of resonant modulation of low-bandwidth (BW < 5 GHz) split-contact semiconductor lasers was recently shown to provide a means of building simple, narrowband mm-wave optical transmitters for subcarrier frequencies approaching 100 GHz.³ Recently, we showed that a split-contact laser is not required for resonant modulation to occur. Resonant modulation of single-contact lasers was demonstrated by utilizing the inherent mm-wave propagation loss (~60 dB/mm at 40 GHz) along the laser contact.⁴ In this paper, we demonstrate mm-wave signal transmission at 35 GHz by resonant modulation of an uncoated single-contact telecommunications-grade distributed feedback (DFB) laser. The simplicity and availability of this device can have significant impact on the cost of narrowband mm-wave optical transmitters. Measurement of the modulation response of this device in the vicinity of the cavity round-trip frequency is presented. Bit-error-rate (BER) is measured for a 35-GHz subcarrier binary-phase-shift-keyed (BPSK) modulated at 2 Mbit/s and transmitted over 2.2 km of singlemode fiber. Carrier-to-noise (CNR) as a function of RF drive is also discussed.

© 1996 Optical Society of America