Spectrally Efficient mm-wave Radio-on-Fiber (PR02-431)

"We propose to demonstrate the key components for 38 GHz mm-wave digital radio-on-fiber optical link with high spectral efficiency: photonic mm-wave modulators and demodulators. Such links show promise as a means to remote large numbers of inexpensiveantennas needed for micro- and pico-cell wireless networks. Our modulator concept is based on the IPITEK photonic mm-wave generator whose low frequency noise and low phase noise characteristics will increase spectral efficiency by allowing tight spacingof channels in allocated bands and high M-ary phase modulation.Mm-wave RoF systems are especially useful to military communications systems developers who seek to achieve a low probability-of-intercept (LPI) characteristic by exploiting the propagation characteristics of mm-wave signals. The low diffraction and/orattenuation of mm-waves during atmospheric transmission allows the establishment of well defined cells. RoF links are a natural means for establishing LPI links between well defined but separated cells and antenna remoting. There is an expanding need for short-range cellular communications networks, like the picocell configuration popular in Japan and Europe. It is estimated that by the beginning of 2005, there will be 1 billion mobile phone users, with the vast majorityalso using the Internet. Mobile and Internet services will converge as people depend on both technologies. To enable such, a vast increase in system capacity