低功耗千兆光互连链路的研制

基于可编程门阵列(FPGA)器件实现了低功耗的高速光互连链路。采用电时分复用(ETDM)技术在1根光纤上实现了G,数据信号的虚拟并行传输,降低了系统成本。链路物理层带宽达1056Mbit／s,链路稳定传输带宽为545Mbit／s,在应用层可得到300Mbit／s的数据传输率。并通过合理的器件选择、动态功耗管理和低功耗编码等设计方法,使系统功耗降低50％。     

Bidirectional multichannel 1.44 Gbit/s lightwave distributionsystem using subcarrier multiplexing

Demonstrates a bidirectional lightwave distribution system that uses subcarrier multiplexing to transmit data to eight nodes from a single head-end laser. Data for each node (180 Mbit/s) and return date (45 Mbit/s digital video) are transmitted as FSK subcarrier, between 2.5 and 5.0 GHz. Penalties from laser nonlinearities, interchannel interference or bidirectional transmission are negligible     

2488Mbit／s SDH系统与设备

由我国自行研制和开发的２４８８Ｍｂｉｔ／ｓ ＳＤＨ复接传输设备和再生中断设备已经成功地应用于从海口市至三亚市长途大容量光缆传输系统。其中还配有若干个１５５Ｍｂｉｔ／ｓ复用设备。本文将简要地介绍该系统的构成及设备特征等情况。     

SDH的映射和同步复用原理（一）

同步复用和映射方法是ＳＤＨ最具特色的内容。本文在简要介绍ＳＤＨ基本知识的基础上，通过对由１４０Ｍｂｉｔ／ｓ信号、２Ｍｂｉｔ／ｓ信号组成ＳＴＭ－１信号的介绍，可使读者对ＳＤＨ有进一步的了解。     

Surface-acoustic-wave multiplexing techniques

Two approaches to frequency division multiplexing using SAW devices are described. The first one uses a 9-channel filter array, where the signal combining and splitting is performed using wide-band power splitters. Two of these filter arrays were used in a data link, with data rates up to 7.5 Mbit/s for a total data rate of 67.5 Mbit/s. The second approach uses offset multistrip couplers to channel a wide-band signal into various narrow-band outputs according to frequency. Consequently, this approach exhibits lower insertion loss and is especially suitable for a large number of channels. An 8-channel MSC multiplexer has been constructed with less than 10-dB insertion loss.     

120 Mbit/S QPSK data and multi-channel TV transmission over 13 kmfibre to a 60 GHz mobile radio link using an electroabsorption modulatoras a transceiver

A broadband analogue fibre-radio millimetre-wave system has been constructed. The system is capable of downstream 120 Mbit/s QPSK data transmission over 13 km of fibre and onward radio transmission at 60 GHz. Simultaneous transmission of downstream data, broadcast video and upstream data over fibre is also incorporated using sub-carrier multiplexing     

1.544 Mbit/s Data Above FDM Voice and Data Under FDM Voice Microwave Transmission

Methods are presented for the transmission of wideband digital signals above and below the frequency division multiplexing (FDM) baseband spectrum of analog microwave systems. In particular, it is shown that a Data Above Voice (DAV) system employing a 1.544 Mbit/s data channel above FDM channels and a Data Under Voice (DUV) system employing 1.544 Mbit/s channel below 720 FDM channels, are practical hybrid systems. Theoretical models of hybrid transmission are disucssed and the DAV/DUV methods are compared. A conceptual hybrid system design procedure is introduced and field measurement results on an 8 hop 6 GHz system are presented, comparing favorably with theoretical predictions.     

Power budget optimisation of WDM network with MSCM control

The authors have experimentally demonstrated a 28.7 dB power budget for simultaneous transmission of 2.5 Gbit/s/node payload data and 80 Mbit/s/node control channels using the multichannel subcarrier multiplexing (MSCM) signalling technique. The power budget is sufficient to support a 234 node MSCM-WDM network with 2.5 Gbit/s/node 10 km radius coverage and 0.25 dB/km fibre attenuation with 0.45 dB/km attenuation, the network can support up to 93 nodes     

Design of integrated services digital broadcasting systems usingmultirate optical fiber code-division multiplexing

This paper presents the design of a new type of integrated services digital broadcasting (ISDB) systems which use a multirate optical fiber code-division multiplexing (OF-CDM) technique. The proposed system can efficiently multiplex various kinds of digital signals with multiple bit rates. This is feasibly achieved by using strict optical orthogonal codes of both auto- and cross-correlation constraints being “1” in multirate OF-CDM systems. Moreover, the low-cost design of OF-CDM transmitters is presented, and experimental demonstrations are also carried out. The measured results show that a transmission distance up to 13 km can be feasibly accomplished by using the proposed transmitter design and the external optical injection-locking scheme. It is expected that the proposed ISDB systems can be employed to cost-effectively transmit fast ethernet (125 Mbit/s), FDDI (125 Mbit/s), ATM (155 Mbit/s), and ESCON (200 Mbit/s) protocol data. Their potential applications include Internet services and multimedia broadcasting, such as videoconferencing, video on demand, HDTV, distance learning, and World Wide Web     

Terminal transmission equipment (TTE) for the SL undersea lightwave system

the SL transmission terminal equipment (TTE) provides the interface between the inland toll transmission network at 139.264 Mbit/s (CCITT 4th level) and the SL undersea cable on a two working and one standby fiber-pair basis. The TTE provides multiplexing of two 139.264- Mbit/s signal and overhead bits per fiber as well as electrical-to-optical signal conversion. End-to-end maintenance features, such as, order-wire, line performance parameters, alarms, and line regenerator supervisory signaling access are also provided.     

Rapid wavelength stabilising control for fast LD wavelength switching

A novel control scheme for fast laser diode (LD) wavelength switching with rapid stabilisation is proposed, which is the key technology for wavelength-division multiplexing (WDM) data cell transfer networks. The obtained characteristics are suitable for 600 Mbit/s asynchronous transfer mode (ATM) cell transfer networks. The proposed control scheme can be applied to over 10 Gbit/s cell speed networks.<>     

Subcarrier multiplexing for multiple-access lightwave networks

This paper describes the applicability of subcarrier multiplexing to lightwave multiple-access networks. It is shown how currently available microwave and lightwave components can be used, by using subcarrier multiplexing, to provide high-capacity networks. For example, the proposed multiple-access network can support 1024 users at a continuous bit rate of 1.5 Mbit/s, per user.     

A versatile ECL multiplexer IC for the Gbit/s range

A new approach to digital multiplexing for communication systems operating in the Gbit/s range is presented. With a single function, monolithically integrated in the established silicon bipolar process, many operations required by the communication system's multiplex equipment are achieved at data rates of up to 3 Gbits/s. The IC is a four-channel multiplexer designed to interface readily with ECL families. Demonstrations of the ICs performance include pseudorandom pattern generation by multiplexing ECL inputs up to 2 Gbits/s, demultiplexing into ECL registers at 1 Gbits/s, clock extraction in a 560 Mbit/s coaxial cable transmission system, and a modulo-n divider technique for timing generation using ECL feedback shift registers for frequencies up to 1.6 GHz. The demonstrations highlight the multiplexer's ability to effectively extend the system speed limit of commercially available ECL from a few hundred Mbits/s to the Gbit/s range. An eight-input multiplexer using three chips in a hybrid assembly is demonstrated multiplexing a static input pattern up to 2.8 Gbits/s.     

Wavelength-division-multiplexed optical transmission system with single-mode fibre and a dual-wavelength hybrid laser light source

Wavelength-division-multiplexed optical fibre transmission over a 45km single-mode fibre using a hybrid dual-wavelength InP CSBH laser light source emitting at 1.3 ?m and 1.5 ?m has been demonstrated. This simple and economic system provides two distinct optical data channels without requiring electronic or optical multiplexing. Optical crosstalk was unobservable while operating the separate optical channels at 1.5 Gbit/s and 90 Mbit/s, respectively. The use of a single light source eliminates multiple fibre-to-source alignments, reducing transmitter packaging costs.     

量子密钥分发和经典光通信波分复用共纤传输研究

研究了量子密钥分发和经典光通信波分复用共纤传输的技术难点和可行性。基于系统重复频率 40 MHz的诱骗态相位编码BB84协议量子密钥分发设备,提出了3种量子信号与经典光信号的波分复用共纤传输方案：单纤双向CWDM共纤传输方案,复用1 550.12 nm波长量子信号、1 310 nm波长时钟信号以及正向1 590 nm波长100 Mbit/s速率光信号和反向1 610 nm波长100 Mbit/s速率光信号,光纤传输距离70 km下密钥成码率达到1.2 kbit/s;双纤双向CWDM共纤传输方案,复用1 550.12 nm波长量子信号、1 610 nm波长时钟信号以及1个波长的同向光信号在1 310 nm波长OOK光信号速率10 Gbit/s,光纤传输距离55 km下,密钥成码率达到1.58 kbit/s;双纤双向DWDM共纤传输方案,复用1 550.12 nm波长量子信号、1 610 nm波长时钟信号以及2个同向波长各自为1 551.72 nm和1 552.52 nm,并模拟100 Gbit/s相干光通信DP-QPSK信号接收功率,光纤传输距离70 km下,密钥成码率达到1.16 kbit/s。     

Feasibility of a 1 Gbit/s/ 565 Mbit/s bidirectional single-mode-fibre subscriber line for B-ISDN using 1279 nm/ 1315 nm wavelength division multiplexing

A laboratory system, transmitting 1 Gbit/s signals to a subscriber station and 565 Mbit/s signals back to a head station via one 20 km-long single-mode fibre, has been realised. Wavelength division multiplexing via two 3 dB fibre couplers of selectivity ?0.04 dB/nm has been used. The experiment demonstrates that bidirectional single-mode-fibre transmission is applicable to a future B-ISDN subscriber network.     

Repeater using two wavelengths for passive optical star networks connection

A repeater for the 32 Mbit/s star-configured optical local area network (SOLARnet) has been developed. This repeater permits a tree-type interconnection of SOLARnets at layer 1 and enlarges the network scale. Wavelength-division multiplexing (WDM) is used to overcome self-collision (collision of the packet header with its packet).     

Mode partition noise caused by wavelength-dependent attenuation in lightwave systems

Power fluctuations among the longitudinal modes of laser diodes cause noise in the received signal after being filtered by a wavelength-dependent attenuation mechanism. We have developed a theoretical model to characterise this noise and studied degradation in lightwave system performance. Power penalties observed in a 432 Mbit/s wavelength division multiplexing system experiment agreed with theoretical predictions.     

Two-channel system demonstration of differential frequency-deviation multiplexing

A two-channel lightwave system using differential frequencydeviation multiplexing (DFDM) is presented. Both 90Mbit/s channels are differentially detected using a fibre interferometer. The performance is independent of the absolute optical frequencies and received state of polarisation. Interchannel interference results in a 1 dB penalty for channel separations of 700 MHz.     

一种应用于波分复用无源光网络系统中的滤波片-PIN-TIA阵列光接收组件

设计并实现了一种将密集波分复用(DWDM)薄膜滤波片与光电探测器PIN以及前置放大器TIA集成封装的光接收组件。通过创新设计单模光纤双芯插针和自聚焦透镜的结构,解决了透过密集波分复用滤波片后的反射光偏离轴线带来的耦合问题。并基于该组件实现了32个密集波分复用通道的解复用与信号检测同时完成的波分复用无源光网络(WDM-PON)系统中上行信道阵列接收模块。测试表明模块满足国际电信联盟(ITU-T)中心波长,最小插入损耗为0.3 dB,最大插入损耗为6 dB,响应速率为100 Mbit/s~1.25 Gbit/s。