OptSim™ Product Overview

OptSim is RSoft's award-winning software tool for the design and simulation of optical communication systems at the signal propagation level. With state-of-the-art simulation techniques, an easy-to-use graphical user interface and lab-like measurement instruments, OptSim provides unmatched accuracy and usability. The software has been commercially available since 1998 and is in use by leading engineers in both academic and industrial organizations worldwide.

OptSim project layout of a DQPSK system. OptSim includes an advanced BER estimator specific for D(Q)PSK systems based on Karhunen-Loeve series expansion.

Benefits Virtual prototyping of the optical communication system for increased productivity and

reduced time-to-market. Optimization of the design for enhanced performance and/or reduced cost. Interfaces with 3rd party tools such as MATLAB®, Cadence Spectre, Liekki Application

Designer, Luna Optical Vector Analyzer.ApplicationsOptSim is ideally suited for computer-aided design of optical communication systems including, but not limited to:

DWDM / CWDM Amplified, e.g. EDFA, Raman, SOA, OPA Advanced Modulation Formats, e.g. D(Q)PSK, Duobinary, OFDM OCDMA / OTDM CATV Digital/Analog

Optical Interconnects FTTx / PON EDC FSO Soliton

FEATURES Only design tool with multiple engines implementing both the Time Domain Split Step

and the Frequency Domain Split Step for the most accurate and efficient simulation of any optical link architecture.

MATLAB® interface makes it easy to develop custom user models using the m-file language and/or the Simulink® modeling environment.

Interface with Liekki Application Designer for the simulation at the system-level of Fiber Lasers & Fiber Amplifiers designed at the device-level with LAD.

Interfaces with laboratory test equipment such as Agilent and Luna to merge simulation with experiment.

Interfaces with device-level design tools such as BeamPROP, GratingMOD, and LaserMOD provide a powerful mixed-level design flow for optoelectronic circuits and systems.

Interfaces with EDA tools such as Berkeley SPICE, Cadence Virtuoso Spectre, and Synopsys HSPICE for a mixed-domain electrical and optical simulation.

Application Programming Interface (API) for programming languages such as C/C++ for the development of custom user models.

Best Fit Laser Toolkit™ makes customizing powerful rate-equation laser model parameters to fit desired performance characteristics easy.

Extensive library of predefined manufacturer components makes it easy to model commercially available devices.

Intuitive and flexible measurement post-processing graphical interface acts like a virtual laboratory instrument.

OptSim - MATLAB cosimulation project layout. An Electro Absorption Modulator with Chirp is modeled using MATLAB m-file programming language. The MATLAB engine is automatically

invoked by OptSim at runtime to simulate the EAM model.

FTTH System with GEPON Access ArchitectureTools used: OptSimThis example demonstrates an OptSim design for FTTH GEPON link. Here we consider typical GEPON FTTH design for downlink with 16 subscribers and 20-km reach. Passive optical network (PON) access architecture is the accepted choice of triple-play (voice, video, and data) service delivery from service providers to the end users in FTTH (fiber-to-the-home) access networks. Three major PON technologies are currently accepted as the basis for FTTH deployments: Broadband PON (BPON), Gigabit PON (GPON), and Ethernet PON (EPON or GEPON). GEPON architecture is specified by IEEE 802.3ah standard and supports Gigabit Ethernet 1.25 Gbps transmission rate for data component in both down- and up-link configuration.

In a PON, the active optoelectronics are situated on either ends of the passive network. An optical line termination (OLT) device is installed in the central office (CO), and an optical network termination (ONT) device is installed on the other end, in or near each home or business site. Fiber distribution is done using a tree-and-branch architecture.

The figure below depicts the layout for this example:

The figure below shows shows full 16-users GEPON configuration - here each ONT block is a compound component.

The diagram below shows the OLT output optical waveforms for data and video signal:

The following figure shows OLT output optical spectra for data and video signals:

Next two figures depict results at the received side for ONT_1, namely, the received eye diagram for data signal and the corresponding BER.

The figure below shows the received RF spectrum of video signal with two tones (channels) recovered, and for comparison the RF video spectrum at the transmitter:

In summary, we described a simple example for typical layout of FTTH GEPON system in OptSim. This layout can be further modified to study links with more specific details and provided components specifications. For example, a fiber trunk can consist of few fiber spans

and splices, the drop-off cables from splitter to users ONTs can be added. The upstream configuration can be studied as well.