Simon P. Yeung

Simultaneous fiber-optic transport and RF phase control of narrow-band millimeter-wave signals using multicontact monolithic semiconductor lasers

We demonstrate fiber-optic transport over 2.2 km of single-mode fiber with continuous RF phase control of narrow-band millimeter-wave signals using a three-section monolithic distributed Bragg reflector (DBR) laser. By injection-locking the laser at the cavity round-trip resonant frequency of 45 GHz, we achieve 360/spl deg/ of continuous, linear RF phase control of the input mm-wave signal by simply varying the bias current into the laser. The RF phase shift of the 45 GHz tone versus bias current into the phase section of the laser is characterized in detail. Carrier-to-noise and locking bandwidth measurements are performed. Dynamic RF phase control of the mm-wave optical transmitter is also demonstrated by modulating the bias current into the phase section of the device, resulting in an RF phase modulated 45 GHz subcarrier with good AM suppression.

Fiber Optic Infrastructure for Wireless Communication Networks

It is clear that to meet the new demands of wireless customers, conventional cellular service providers and upcoming Personal Communication Service (PCS) providers for conventional phone service and high bandwidth wireless LAN must upgrade their networks to provide complete radio coverage. This evolution has motivated the need for low-cost systems that transport radio signals to and from areas of poor signal coverage. The most important area where this problem must be solved is inside of buildings, since this is where people spend most of their time. Unfortunately, the in-building enviroment is also the ost challenging area to provide radio coverage due to severe attenuation and multi-path effects. The problem must be tackled from the viewpoint of optimization of performance/cost ratio of the network. In this paper, we describe a system-level approach to tackle this problem. We demonstrate how one can trade-off hardware performance, which represent cost, with proper choice of system architecture which includes, among other factors, in-buiding radio environment, to arrive at an optimum network solution technically and economically.

Millimeter wave signal transmission using uncoated telecommunications-grade distributed feedback lasers

Summary form only given. In conclusion, we have demonstrated efficient fiber-optic transport at mm-wave frequencies using an uncoated single contact DFB laser. These results indicate that simple, low-cost mm-wave optical transmitters can be constructed for fiber-fed antennas in mm-wave wireless picocellular networks and mm wave phased-array antenna systems.

Optical transmission of narrowband mm-wave signals using telecommunications-grade DFB lasers

Using an uncoated monolithic single-contact distributed feedback (DFB) laser, transmission of 2 Mb/s data at a subcarrier frequency of 35 GHz over 2.2 km of optical fiber by resonant modulation is demonstrated. Modulation response of 60 MHz with more than 1 GHz of enhancement at round trip frequency, carrier-to-noise ratio and bit-error-rate results are reported. The tolerance of the resonant round-trip frequency to the DFB facet cleaving process and the device length uncertainty due to cleaving is also addressed in detail by computer simulation.

Transmission of millimeter-wave signals using uncoated telecommunications-grade distributed feedback lasers

Transmission of 2-Mb/s data at a subcarrier frequency of 35 GHz over 2.2 km of optical fiber by resonant modulation of an uncoated monolithic single-contact distributed feedback (DFB) laser is demonstrated. Modulation response, carrier-to-noise ratio and bit-error-rate results are reported. The tolerance of the resonant round-trip frequency to the DFB facet cleaving process and the device length uncertainty due to cleaving is also addressed in detail by computer simulation.