Hiroshi Ishii

Field Trial of 100-km Reach Symmetric-Rate 10G-EPON System Using Automatic Level Controlled Burst-Mode SOAs

This paper reports the worlds first field trial of a 100-km reach symmetric-rate ten gigabit Ethernet passive optical network (10G-EPON) system that uses optical-amplifier-based PON repeaters. Semiconductor optical amplifiers (SOAs) are utilized to handle the 10G-EPON wavelength allocation defined in IEEE802.3av; a fast automatic level control technique is applied to cascaded SOAs for upstream amplification to achieve high gain and wide input dynamic range. An electronic dispersion compensation technique is also applied for downstream detection. These techniques support a 79.5-dB loss budget and 100-km reach transmission with 40 km span lengths. In a field trial, we successfully demonstrate bidirectional real-time uncompressed high-definition television signal transmission over installed standard single-mode fiber links.

Burst-mode compound optical amplifier with automatic level control circuit that offers enhanced setting flexibility in a 10 Gb/s-class PON

Proposed amplifier provides 10 G/s-class PONs with the two-dimensionally expanded dynamic range of 22.5 dB with very wide repeater-OLT link loss margin, both of which allow much greater flexibility in locating the repeater.

ALC burst-mode optical fiber amplifiers for 10 Gb/s-class long-reach PONs

This paper proposes a burst-mode optical fiber amplifier (OFA) that consists of a combination of an automatic gain controlled praseodymium-doped fiber amplifier (AGC-PDFA), a fast automatic level controlled circuit (ALC), and a PDFA with just forward pumping. The second PDFA is used as a booster to achieve high gain, over 20 dB. The combination of AGC and ALC techniques suppresses optical surge generation against strong burst signal inputs and also prevents overloading of the burst-mode receivers; it provides OFA-based passive optical network (PON) repeaters with wide input dynamic range and solves the near-far problem in upstream transmission in long-reach PONs. We experimentally compare the operating range of the proposed burst-mode PDFA with that of a conventional burst-mode PDFA. Experiments show that the proposed PDFA achieves a much wider operating area than a conventional PDFA; a wide dynamic range in an access span of 17.5 dB, which is equivalent to the input dynamic range of the burst-mode receiver used in 10 gigabit Ethernet PON (10G-EPON), is obtained with an allowable loss margin of 14 dB in a trunk span. A maximum link budget of 55 dB is achievable.

Pattern Effect Suppression by Injecting Directly Modulated Synchronized Gain-Clamping Light Using Inverted Signal for PON Application of SOA

This paper presents and demonstrates a simple pattern effect suppression technique for the downstream repeater and the upstream booster semiconductor optical amplifiers (SOAs) of an SOA-based, optically amplified passive optical network (PON) system. The synchronized gain-clamping light injection technique is applied to an SOA mainly consisting of an optical-electrical-optical converter. The feasibility of the technique is confirmed experimentally by applying it to a downstream amplification repeater in a Gigabit Ethernet PON (GE-PON) and a upstream booster amplifier in a 10G-EPON with a high output power optical network unit (ONU). In both cases, the pattern effect is significantly suppressed and the system loss budget is greatly improved. For the GE-PON repeater a large access span loss of over 40 dB was achieved with a trunk span distance of 51.8 km, and for the 10G-EPON the loss budget was increased to over 40 dB by using high-output power ONU.

Applicable area estimation of bidirectional optical amplifiers to 10-Gb/s class long-reach PON systems

We analytically investigate the applicable areas of bidirectional optical amplifiers as regards 10-G/s class long-reach PONs and also discuss technical issues with both DFA and SOA based PON repeaters in terms of allowable repeater layout.

1G / 10G coexistence long-reach PON system using ALC burst-mode SOAs

This paper evaluates the allowable loss ranges of 1G / 10G dual-rate symmetric long-reach 10 gigabit Ethernet passive optical networks (10G-EPONs) that employ cascaded semiconductor optical amplifiers with fast automatic level controlled circuit (ALC-SOAs) for upstream transmission and a single SOA for downstream transmission. Experiments show that our optical amplifiers have the ability to achieve the maximum loss budget of 61dB with very wide loss ranges for both access and trunk spans; they support up to 80km transmission (60km trunk span and 20km access span).

Optically-amplified PON system using XGM-based ALC technique

This paper describes an automatic level control (ALC) technique that utilizes cross gain modulation (XGM)-based wavelength conversion to expand the upstream transmission operating areas in optically-amplified passive optical network (PON) systems. We conduct experiments to evaluate the allowable link budgets of optically-amplified PON systems using XGM-based ALC (XGM-ALC), and also show that we can achieve a large operating area with a dynamic range in a trunk span of 18.5dB against an allowable link loss range for an access span of between 8.0 and 20.0dB. The allowable link loss range of an access span can be expanded to between 8.0 and 25.0dB if the dynamic range in the trunk span is reduced to 15.5dB. A total link budget of 55.0dB is achieved.