Performance of Resonant Modulation in the Millimeter-Wave Frequency Range: Multi-Subcarrier Modulation

Abstract

Optical transmitters capable of efficiently transporting several millimeter-wave (mm-wave) subcarriers to/from fiber-fed antenna sites in indoor/outdoor mm-wave mobile/point-to-point wireless networks are of considerable importance in mm-wave free space links [101, 102]. Future deployment of a fiber infrastructure in these systems rests primarily upon the availability of low-cost mm-wave optical transmitters. Optical transmission of a single narrowband (50 Mb s^− 1) channel at 45 GHz was demonstrated using resonant modulation of an inexpensive, conventional semiconductor laser with a baseband direct modulation bandwidth of < 5 GHz [103]. It was shown that this technique provides a means of building simple, low-cost, narrowband ( < 1 GHz) mm-wave subcarrier optical transmitters for frequencies approaching 100 GHz. In this chapter, the multichannel analog and digital performance of these transmitters at a subcarrier frequency of ∼ 40 GHz are described.