C.C. Lee

Composite-second-order improvement of 15 dB in an optically amplified 110-km AM-VSB CATV transport system using chirped fiber grating

To improve system composite-second-order (CSO) of an optically amplified AM-VSB CATV transport system, we investigate the system using chirped fiber grating (CFG) and dispersion-compensating fiber (DCF) separately. We find that the CFG technique is superior to the DCF one in both CSO and carrier-to-noise ratio with satisfied composite-triple-beat performance.

Reduction of cross-phase-modulation-induced crosstalk by using chirped fiber grating in WDM AM-VSB CATV transmission systems

Cross talk induced by cross-phase modulation (XPM) in a 1.55-/spl mu/m WDM CATV transport system can be effectively improved, theoretically and experimentally, from -55.4 dBc to 69.8 dBc by using the chirped fiber grating and polarization control technique.

System demonstration of wavelength-tunable multiple-ITU-WDM-channel add/drop multiplexer using an optical-switch pair and fiber Bragg gratings

Summary form only given. A wavelength-tunable four-ITU-WDM-channel add/drop multiplexer using a mechanical-switch pair and fiber Bragg gratings is demonstrated and studied. Either single- or multichannel add-drop tunability can be realized according to the fibre Bragg grating (FBG) arrangement. Negligible power penalty has been achieved in a 2.5 Gbit/s/spl times/4 four WDM-wavelength system experiment. This simple, cost-effective device may find important applications in WDM networks to provide more flexibility for reconfiguration requirements and to enhance network survivability.

Multiwavelength dynamically selective cross-connect based on fiber Bragg gratings and optical switches

We have demonstrated a dynamically selective multiwavelength cross-connect switch based on fiber Bragg gratings (FBGs) and optical switches. Dynamically single- or multi-channel selectivity can be realized by connecting the appropriate FBGs. Negligible power penalty was observed in a 2.5 Gb/s/spl times/6 WDM-wavelength 100-km system experiment. The device may find applications in all-optical WDM system for more reconfiguration flexibility and network survivability.

Hybrid 10-Gb/s, 2.5-Gb/s, 64-QAM, and AM-VSB high-capacity wavelength-division-multiplexing transport systems using standard single-mode fiber and LEAF fibers

Summary form only given.We have demonstrated a four-wavelength hybrid WDM system with OC-48 and OC-192 baseband digital signals, AM-VSB analog video, and QAM digital video signals over 100-km of either single mode fibre (SMF) or LEAF link. The hybrid WDM system, which simultaneously transmits 80 AM-VSB channels, 110 64-QAM channels, one OC-48 and one OC-192 baseband channels, offers satisfactory system performances.

Large nonblocking multiwavelength cross-connects based on fiber Bragg gratings for WDM networks

Multi-wavelength cross-connects (WXCs) will play a key role to provide more reconfiguration flexibility and network survivability in wavelength-division-multiplexing (WDM) transport networks. In this paper, we utilize three different fiber-Bragg-grating (FBG) based P-type, S-type, and N-type building blocks with optical circulators and related control devices for constructing large rearrangeably non-blocking N X N WXCs. The P-type building block is composed of certain parallel FBG-element chains placed between the control device of two large mechanical optical switches (OSWs). The S-type building block consists of a series of FBG elements and the control device of 2 X 2 OSWs. The non-switched N-type building block includes a series of FBG elements with appropriate stepping motor or PZT control devices. Large N X N WXC structures, with minimum number of required constitutive elements, based on a three-stage Clos network are then constructed. We investigate their relevant characteristics, compare the required constitutive elements, and estimate the dimension limits for these WXC architectures.

Optical label swapping for IP-WDM networks using self-seeded Fabry-Perot laser label and fiber Bragg gratings

We experimentally demonstrate a simple optical label swapping technique for 10 Gb/s IP-WDM networks using the self-seeded Fabry-Perot laser label and fiber Bragg gratings. Negligible power penalty of 0.1 - 0.2 dB can be achieved for both the 120-MHz label and the swapped label. In addition, tolerable power penalty of 0.6 dB for the data payload is obtained.

In-service supervisory AM-VSB CATV supertrunk system using 1310/1650 nm optical time domain reflectometer

Summary form only given. We have demonstrated an in-service supervisory CATV video transport system using both the 1310 nm and 1650 nm OTDR for the first time to our knowledge. Simultaneous fiber-fault location and EDFA status monitoring have been achieved without degrading the video performance in a 80-NTSC-channel 77.6-km fiber link. This supervisory technique applied to the CATV supertrunk link can efficiently improve the system reliability and reduce the disaster-repairing time of EDFA-failure and link-faults.

Baseband video distortion due to on-line OTDR monitoring at 1.65 /spl mu/m with negligible CNR/CSO/CTB degradation

Summary form only given. In conclusion, we have investigated the SRS effect in OTDR-monitored AM video lightwave system. Negligible CNR/CSO/CTB degradation, but accompanied with baseband video distortion, due to the OTDR monitoring is only observed at 1650 nm. This makes the 1310-nm wavelength a good candidate for in-service monitoring. After reducing the peak power of the OTDR probe pulses at the expense of reduced dynamic range, the 1650-nm wavelength can also be used in lightwave CATV system.

In-service fault locating and supervisory CATV optical distribution network using WDM-based OTDR and optical switches

We demonstrate an in-service fault-locating and supervisory technique for multi-staged CATV optical distribution networks. The requirements of ultra-high dynamic range of an optical time domain reflectometer (OTDR) to diagnose the network can be tremendously relaxed by the introduction of optical switch and wavelength-division-multiplexing (WDM) technique. Any faults of the fiber links whether before, after, or between optical splitters can be located. The system operation is experimentally demonstrated in a two- staged eight-optical-node CATV distribution network. The degradation of system performance of carrier-to-noise ratio, composite second order, and composite triple beat due to in- service OTDR operation can be neglected. This surveillance system can provide real-time testing, saving the cost of dispatching a technician to perform routine testing and reducing the time taken to identify faults after an outrage occurs.