53 research outputs found
A global routing technique for wave-steered design methodology
Wave-Steering is a new circuit design methodology to realize high throughput circuits by embedding layout friendly structures in silicon. Latches guarantee correct signal arrival times at the input of synthesized modules and maintain the high throughput of operation. This paper presents a global routing technique for networks of wave-steered blocks. Latches can be distributed along interconnects. Their number depends on net topologies and signal ordering at the inputs of wave steered blocks. here, we route nets using Steiner tree heuristics and determine signal ordering and latch positions on interconnect. The problem of total latch number minimization is solved using SAT formulation. Experimental results on benchmark circuits show the efficiency of our technique. We achieve on average a 40% latch reduction at minimum latency over un-optimized circuits operating at 250 MHz in 0.25 μm CMOS technology</p
Introduction to Logic Circuits & Logic Design with VHDL
The overall goal of this book is to fill a void that has appeared in the instruction of digital circuits over
the past decade due to the rapid abstraction of system design. Up until the mid-1980s, digital circuits
were designed using classical techniques. Classical techniques relied heavily on manual design
practices for the synthesis, minimization, and interfacing of digital systems. Corresponding to this design
style, academic textbooks were developed that taught classical digital design techniques. Around 1990,
large-scale digital systems began being designed using hardware description languages (HDL) and
automated synthesis tools. Broad-scale adoption of this modern design approach spread through the
industry during this decade. Around 2000, hardware description languages and the modern digital
design approach began to be taught in universities, mainly at the senior and graduate level. There
were a variety of reasons that the modern digital design approach did not penetrate the lower levels of
academia during this time. First, the design and simulation tools were difficult to use and overwhelmed
freshman and sophomore students. Second, the ability to implement the designs in a laboratory setting
was infeasible. The modern design tools at the time were targeted at custom integrated circuits, which
are cost- and time-prohibitive to implement in a university setting. Between 2000 and 2005, rapid
advances in programmable logic and design tools allowed the modern digital design approach to be
implemented in a university setting, even in lower-level courses. This allowed students to learn the
modern design approach based on HDLs and prototype their designs in real hardware, mainly field
programmable gate arrays (FPGAs). This spurred an abundance of textbooks to be authored teaching
hardware description languages and higher levels of design abstraction. This trend has continued until
today. While abstraction is a critical tool for engineering design, the rapid movement toward teaching only
the modern digital design techniques has left a void for freshman- and sophomore-level courses in digital
circuitry. Legacy textbooks that teach the classical design approach are outdated and do not contain
sufficient coverage of HDLs to prepare the students for follow-on classes. Newer textbooks that teach
the modern digital design approach move immediately into high-level behavioral modeling with minimal
or no coverage of the underlying hardware used to implement the systems. As a result, students are not
being provided the resources to understand the fundamental hardware theory that lies beneath the
modern abstraction such as interfacing, gate-level implementation, and technology optimization.
Students moving too rapidly into high levels of abstraction have little understanding of what is going
on when they click the “compile and synthesize” button of their design tool. This leads to graduates who
can model a breadth of different systems in an HDL but have no depth into how the system is
implemented in hardware. This becomes problematic when an issue arises in a real design and there
is no foundational knowledge for the students to fall back on in order to debug the problem
Introduction to Logic Circuits & Logic Design with Verilog
The overall goal of this book is to fill a void that has appeared in the instruction of digital circuits over
the past decade due to the rapid abstraction of system design. Up until the mid-1980s, digital circuits
were designed using classical techniques. Classical techniques relied heavily on manual design
practices for the synthesis, minimization, and interfacing of digital systems. Corresponding to this design
style, academic textbooks were developed that taught classical digital design techniques. Around 1990,
large-scale digital systems began being designed using hardware description languages (HDL) and
automated synthesis tools. Broad-scale adoption of this modern design approach spread through the
industry during this decade. Around 2000, hardware description languages and the modern digital
design approach began to be taught in universities, mainly at the senior and graduate level. There
were a variety of reasons that the modern digital design approach did not penetrate the lower levels of
academia during this time. First, the design and simulation tools were difficult to use and overwhelmed
freshman and sophomore students. Second, the ability to implement the designs in a laboratory setting
was infeasible. The modern design tools at the time were targeted at custom integrated circuits, which
are cost- and time-prohibitive to implement in a university setting. Between 2000 and 2005, rapid
advances in programmable logic and design tools allowed the modern digital design approach to be
implemented in a university setting, even in lower-level courses. This allowed students to learn the
modern design approach based on HDLs and prototype their designs in real hardware, mainly fieldprogrammable gate arrays (FPGAs). This spurred an abundance of textbooks to be authored, teaching
hardware description languages and higher levels of design abstraction. This trend has continued until
today. While abstraction is a critical tool for engineering design, the rapid movement toward teaching only
the modern digital design techniques has left a void for freshman- and sophomore-level courses in digital
circuitry. Legacy textbooks that teach the classical design approach are outdated and do not contain
sufficient coverage of HDLs to prepare the students for follow-on classes. Newer textbooks that teach
the modern digital design approach move immediately into high-level behavioral modeling with minimal
or no coverage of the underlying hardware used to implement the systems. As a result, students are not
being provided the resources to understand the fundamental hardware theory that lies beneath the
modern abstraction such as interfacing, gate-level implementation, and technology optimization.
Students moving too rapidly into high levels of abstraction have little understanding of what is going
on when they click the “compile and synthesize” button of their design tool. This leads to graduates who
can model a breadth of different systems in an HDL but have no depth into how the system is
implemented in hardware. This becomes problematic when an issue arises in a real design and there
is no foundational knowledge for the students to fall back on in order to debug the problem
Embedded System Design
A unique feature of this open access textbook is to provide a comprehensive introduction to the fundamental knowledge in embedded systems, with applications in cyber-physical systems and the Internet of things. It starts with an introduction to the field and a survey of specification models and languages for embedded and cyber-physical systems. It provides a brief overview of hardware devices used for such systems and presents the essentials of system software for embedded systems, including real-time operating systems. The author also discusses evaluation and validation techniques for embedded systems and provides an overview of techniques for mapping applications to execution platforms, including multi-core platforms. Embedded systems have to operate under tight constraints and, hence, the book also contains a selected set of optimization techniques, including software optimization techniques. The book closes with a brief survey on testing. This fourth edition has been updated and revised to reflect new trends and technologies, such as the importance of cyber-physical systems (CPS) and the Internet of things (IoT), the evolution of single-core processors to multi-core processors, and the increased importance of energy efficiency and thermal issues
Embedded System Design
A unique feature of this open access textbook is to provide a comprehensive introduction to the fundamental knowledge in embedded systems, with applications in cyber-physical systems and the Internet of things. It starts with an introduction to the field and a survey of specification models and languages for embedded and cyber-physical systems. It provides a brief overview of hardware devices used for such systems and presents the essentials of system software for embedded systems, including real-time operating systems. The author also discusses evaluation and validation techniques for embedded systems and provides an overview of techniques for mapping applications to execution platforms, including multi-core platforms. Embedded systems have to operate under tight constraints and, hence, the book also contains a selected set of optimization techniques, including software optimization techniques. The book closes with a brief survey on testing. This fourth edition has been updated and revised to reflect new trends and technologies, such as the importance of cyber-physical systems (CPS) and the Internet of things (IoT), the evolution of single-core processors to multi-core processors, and the increased importance of energy efficiency and thermal issues
Imaging Based Beam Steering for Optical Communication and Lidar Applications
Optical beam steering is a key component in any application that requires dynamic (i.e. realtime control) of beam propagation through free-space. Example applications include remote sensing, spectroscopy, laser machining, targeting, Lidar, optical wireless communications (OWC) and more. The pointing control requirements for many of these applications can be met by traditional mechanical steering techniques; however, these solutions tend to be bulky, slow, expensive, power hungry and prone to mechanical failures leading to short component lifetimes. Two emerging applications, Lidar imaging and OWC, truly need improved beam-steering capabilities to flourish and support the advancement of self-driving cars or relieve the congestion in radio-frequency wireless networks, respectively. We consider the novel requirements of these applications during development of a new beam-steering technology. We introduce imaging-based beam steering (IBBS) that uses an imaging transform between spatial and directional domains to implement a new method of electronic beam-steering. We introduce this concept while focusing on transmitters (Tx) for OWC but the pointing control mechanism is bi-directional supporting both transmit and receive functionality, even out of the same aperture; likewise, features that make this solution compelling for OWC are also great for Lidar imaging. In IBBS, an array of high-speed sources are positioned at the focal plane of a lens and the lens passively collects, collimates and steers the beam into a conjugate direction. Steering is accomplished by selecting which source to use for an OWC link. This gives a coarse, pixelated beam-steering control that is well-suited for short-range OWC such as indoor communications and we present a prototype bulb for this application. Notably, multiple sources can be utilized at once with each steered into its conjugate directions and this presents the first beam-steering technology that supports multiple beams out of a single aperture; this feature uniquely supports multiplexed communications and fast, high-resolution Lidar imaging
Hidden Markov Models
Hidden Markov Models (HMMs), although known for decades, have made a big career nowadays and are still in state of development. This book presents theoretical issues and a variety of HMMs applications in speech recognition and synthesis, medicine, neurosciences, computational biology, bioinformatics, seismology, environment protection and engineering. I hope that the reader will find this book useful and helpful for their own research
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