Optical switching can be performed by using optical amplifiers combined with a passive waveguiding network. Recently, most of the effort in optical amplifier switch modules have been focused on monolithic switches in which the entire device is fabricated on an InP substrate together with the semiconductor optical amplifiers (SOAs). In this paper, we investigate the use of SOAs with passive poly...

This paper presents large capacity switching systems for a local network using the broadcast-and-select (B&S) architecture. The B&S switching system, based on optical time-division multiplexing (OTDM), can provide several hundreds of Gbit/s by using a nonlinear optical switch as the timechannel selector. Moreover, the combination of OTDM and wavelength-division multiplexing (WDM) can realize th...

Transparent optical nodes (TONs), such as all-optical switches and erbium-doped fiber amplifiers, are an increasingly important part of wavelength-division multiplexed (WDM) networks. Our goal in this paper is to consider how quality of service (QoS) may be monitored at such TONs. The question is particularly important as access to WDM networks, and associated security concerns, increase. Our p...

All-optical switching fabrics will be a significant breakthrough in order to relieve the capacity bottleneck of electronic-switched networks. These devices allow switching traffic directly in the optical domain, avoiding the need of several optical-to-electrical-to-optical conversions. In this paper, the state of the art of optical switching fabrics is reviewed, by outlining the main technologi...

In this paper a new 8-bit 50-Msample/s CMOS digital-to-analog converter (DAC) is presented. The circuit employs 9 operational transconductance amplifiers (OTAs) and CMOS transistors as switching circuit. The proposed DAC is simulated using SPICE simulation program with 3μm CMOS technology. Simulation results shows verify good performance of the circuit.

All-optical 2R logic regeneration is demonstrated using a vertical cavity semiconductor optical amplifier. The optical switching threshold is 1 μW, with 10 dB gain and >6:1 (8dB) extinction ratio. Performance limits are also discussed. ©2003 Optical Society of America OCIS codes: (190.1450) Bistability; (200.4660) Optical Logic; (250.5980) Semiconductor Optical Amplifiers; (230.4320) Nonlinear ...

This paper discusses system aspects and describes experimental demonstrations of nanosecond wavelength tuning in laser diode structures. Both tunable transmitters and tunable filters are considered. The dependence of the refractive index on the carrier density in semiconductors is exploited to obtain fast wavelength tuning. Experimentally, switching times of < 15 ns have been demonstrated in a ...

This article is based on “Class-E High-Efficiency Power Amplifiers, from HF to Microwave,” Proceedings of the IEEE International Microwave Symposium, June 1998, Baltimore; and “ClassE Switching-Mode High-Efficiency Tuned RF Microwave Power Amplifier: Improved Design Equations,” Proceedings of the IEEE International Microwave Symposium, June 2000, Boston; both by Nat Sokal, © IEEE 1998, 2000.—Ed.

Wide band code division multiple access (WCDMA) signals, transmitted by the base station high power amplifiers (HPAs), show high peak to average power ratios (PAPR), which results in nonlinear distortions. In this paper, using computer simulations effect of using a predistorted HPA on the symbol error rate (SER) of multi-user detectors in terms of output back-off (OBO) in the transmit power...

The previous literature on tuned power amplifiers has not made clear the fundamental differences between amplifiers in which the output device acts 1) as a current source, or 2) as a switch. Previous circuits have often operated in contradiction to their design assumptions, resulting in the need for “cut-and-try” design. The new class of amplifiers deseribed here is based on a load network synt...