Design and Analysis of New Erbium Doped Fiber Amplifiers and Lasers

Erbium doped fiber amplifiers and lasers have a great impact on optical communication due to their ideal advantages for the compensation of light energy during transmission through the fiber optic systems. This has been the focus of many research groups. Replacing the bottleneck electronic amplifier by the optical amplifier, a great improvement is made for the optical communication systems. New configurations have been conceived and realized in this thesis. They have shown a great enhancement in amplifier and laser performance parameters. Several new configurations, for example double pass with filter which also supports multiple wavelengths, have been demonstrated and investigated. The design and performance parameters of the new configurations are thoroughly characterized, showing an improvement in gain, noise figure output power flatness efficiency and side mode suppression ratio. Enhancement of results has been experimentally demonstrated, where a higher gain (56dB) and flat output power (<0.7dB), a higher signal to noise ratio (77dB) and a higher efficiency (22%) are demonstrated

High-gain erbium-doped fiber amplifier incorporating a double-pass amplification technique as a preamplifier

We present a high-gain erbium-doped fiber amplifier to be utilized as a preamplifier. A double-pass amplification technique is used in the first-stage amplifier together with a tunable bandpass filter. The secondstage amplifier is a counter-pumped configuration and another tunable bandpass filter is utilized to filter out amplified spontaneous emission from the first-stage amplifier. This design is able to produce a high gain of 55.6 dB and a noise figure of 6.02 dB at 1530 nm with a signal power of −45 dBm. The receiver sensitivity measurement shows that the proposed amplifier improves the minimum detectable power from −33.7 to −40.8 dBm for a bit-error rate of 10−11 at 155 Mbps

Enhanced structure of a double-pass erbium-doped fiber amplifier for multiple wavelength amplifications.

We demonstrate an enhanced double-pass erbium-doped fiber amplifier for multichannel amplification. The multichannel selection is formed by combining a demultiplexer and a multiplexer together in the fiber-loop mirror. The structure is able to filter out the amplified spontaneous emission that saturates the amplifier gain in the small signal regime. The maximum average gain of 47.2 dB is obtained with a gain enhancement of 12.8 dB at a -50-dBm signal power per channel. The noise figure penalty is almost negligible for a signal power per channel of less than -15 dBm

The influence of EDFA’s configurations on the behavioral trends of gain and noise figure

Various configurations have been conceived and tested for improvement of the gain and noise figures in Erbium doped fiber amplifiers (EDFA’s). Single pass (SP), double pass (DP), triple pass (TP) and quadruple pass (QP), are employed in the investigation. The highest gain and highest noise figure (NF) of 54dB and 7dB respectively are obtained at -50 dBm input power with 90 mW pump power using the QP configuration, while and the lowest gain of 23dB and lowest NF of 3dB are obtained at -50 dBm input power with 90 mW pump power for SP configuration

A high gain EDFA using double-pass dual-stage amplification

A new configuration of an Erbium Doped Fiber Amplifier is proposed. Double-Pass amplification in a Dual-Stage using a fiber loop-back is incorporated with a Tunable Band Pass Filter. Spontaneous emission is filtered-out in the mid-section to ensure efficient amplification of the signal as it propagates along the fiber. High gain of 54dB is achieved for - 50dBm signal power at 1550nm. The two stages were pumped by laser diodes operating at 980nm with 10mW and 90mW respectively

The Influence of EDFA’s Configuration on the Behavioral Trends

Abstract Various configurations have been conceived and tested for improvement of the gain and noise figures in Erbium doped fiber amplifiers (EDFA&apos;s). Single pass (SP), double pass (DP), triple pass (TP) and quadruple pass (QP)

Double pass optical amplifier.

A double pass optical amplifier comprises a first three port circulator (1) having an input signal port connected to at least one pumping laser (2) and an output signal port and a third port connected to one end of a length of doped optical fibre (4),a second three port circulator (5) connected to the other end of the length of doped optical fibre (4) and a loop of undoped optical fibre (6) incorporating at least one band pass filter (7), for allowing passage only of the input signal or signals and filtering out the amplified spontaneous emissions from the doped optical fibre (4), connected between the other two ports of the second circulator (5) to direct the filtered signal back through the length of doped optical fibre (4) to the output signal port of the first circulator

An efficient background suppression ratio and output power using a novel fiber loop mirrors technique

This paper demontrates a novel configuration of a linear cavity erbium-doped fiber laser using fiber loop mirrors to effectively suppress the noise generated by the amplified spontaneous emission (ASE). A tunable filter is deployed in each fiber loop mirror to create a narrow passband for the selected mode. The fiber laser produces high background suppression ratio (BSR) of more than 75 dB from 1525 to 1565 nm at the output coupling of 95%. There is no residual ASE detected at the output to verify the effectiveness of the noise filtering in the proposed fiber laser. Low threshold powers are obtained in the range of 2.5-3 mW and the peak power variation is smaller than 1.6 dB. (c) 2005 Elsevier Ltd. All rights reserved