The future (third-generation) mobile communications system will provide not only voice and low-speed data services, but also video and high-speed data services. It will eventually have the capability for wireless multimedia communications. As a radio-access technique for such a system, the code-division multiple access (CDMA) has been considered in many potential third-generation systems includ...

The optical CDMA and WDM systems have been of widespread implementation for local and metro access network. This is because optical CDMA systems provide users both simultaneous and asynchronous access to networks with high security [1], and WDM systems provide a relatively high transmission capacity [2]. In addition, optical CDMA can be overlaid onto existing WDM networks in order to enhance th...

Code division multiple access (CDMA) is a highly flexible multiple access protocol, however, significant signal bandwidth expansion is required. Given the Terahertz pass band of optical fiber, the frequency spreading of the CDMA signal is no impediment, provided it can be accomplished optically. Among wide variants of optical CDMA techniques, only a spectral encoding based approach [1] has pene...

We describe a heterogeneous simulation framework in which conventional simulation models and the DEVS (Discrete Event Systems Specification) models can be interoperable. The framework conceptually consists of three layers: the model layer, the DEVS layer, and the HLA (High Level Architecture) layer. The model layer has a collection of heterogeneous simulation models, such as DEVS, CSIM, SLAM, a...

The simulation of computer architecture is an important task in the development of new architectures. Exploring novel architectures requires simulations which are flexible, easy to produce, and high performance. The greater these characteristics, the more efficiently the design space can be explored. A number of simulation frameworks exist which can assist the architect in creating new simulato...

We develop a new switch-level simulator, CSim, for MOS transistor cells. CSim simulates cells without circuit parameters, such as the sizing of transistors. To tackle the challenges caused by the lack of circuit parameters, a new transistor-level levelization algorithm is developed. SPICE simulator is used as reference simulator, CSim is accurate in a sense that the simulation results for a cel...

There are many research and clinical settings in which accurate objective measures of speech intelligibility are either necessary or highly desirable. Unfortunately, most objective measures of intelligibility require blinded human listeners to classify speech tokens obtained from the talker whose speech intelligibility is to be measured, a process that can be both costly and time-consuming to c...