Discussing embedded systems in general is difficult, Because each embedded system is unique. Rather than presenting a list of general principles for handling embedded development issues, this book presents examples of problems encountered and solutions to those problems using real hardware and software. In that sense, it is a “cookbook” for developers that offers design “recipes” that can be elaborated on or modified as needed to solve other design problems.
Because WDM networks are circuit switched loss networks blocking may occur Because of lack of resources. Also in circuit switched networks many paths use the same links. This toolbox answers the question how different paths with different loads influence on each other and what is the blocking on each of the defined path. Toolbox is capable of computing blocking for three different WDM network types: with no wavelength conversion, with full wavelength conversion and with limited range wavelength conversion. It is worth noting that case for full conversion can be usefull for any circuit switched network without additional constraints (i.e. wavelength continuity constraint in WDM), for example telephone network.
Toolbox contains also scripts for defining network structures (random networks, user defined networks) and traffic matrixes. Three graph algorithms for shortest path computation are also in this toolbox (they are used for traffic matrix creation).
You may read code Because you have to-to fix it, inspect it, or improve it. You may read code the way an engineer examines a machine--to discover what makes it tick. Or you may read code Because you are scavenging--looking for material to reuse.
Code-reading requires its own set of skills, and the ability to determine which technique you use when is crucial. In this indispensable book, Diomidis Spinellis uses more than 600 real-world examples to show you how to identify good (and bad) code: how to read it, what to look for, and how to use this knowledge to improve your own code.
Fact: If you make a habit of reading good code, you will write better code yourself.
Abstract: Alexander Graham Bell patented twisted pair wires in 1881. We still use them today Because they work so well. In addition we have the advantage ofincredible computer power within our world. Circuit simulators and filter design programs are available for little or no cost. We combine the twisted pair and lowpassfilters to produce spectacular rejection of radio frequency interference (RFI) and electromagnetic interference (EMI). We also illustrate use of a precision resistorarray to produce a customizable differential amplifier. The precision resistors set the gain and common mode rejection ratios, while we choose the frequencyresponse.
Designers of signal receiver systems often need to performcascaded chain analysis of system performancefrom the antenna all the way to the ADC. Noise is a criticalparameter in the chain analysis Because it limits theoverall sensitivity of the receiver. An application’s noiserequirement has a signifi cant infl uence on the systemtopology, since the choice of topology strives to optimizethe overall signal-to-noise ratio, dynamic range andseveral other parameters. One problem in noise calculationsis translating between the various units used by thecomponents in the chain: namely the RF, IF/baseband,and digital (ADC) sections of the circuit.
Recent advances in low voltage silicon germaniumand BiCMOS processes have allowed the design andproduction of very high speed amplifi ers. Because theprocesses are low voltage, most of the amplifi er designshave incorporated differential inputs and outputs to regainand maximize total output signal swing. Since many lowvoltageapplications are single-ended, the questions arise,“How can I use a differential I/O amplifi er in a single-endedapplication?” and “What are the implications of suchuse?” This Design Note addresses some of the practicalimplications and demonstrates specifi c single-endedapplications using the 3GHz gain-bandwidth LTC6406differential I/O amplifi er.
Abstract: A resistive feedback network is often used to set the output voltage of a power supply. A mechanical potentiometer (pot)conveniently solves the problem of adjusting a power supply. For easier automatic calibration, a mechanical pot can be replaced witha digital pot. This application note presents a calibration solution that uses a digital pot, Because digipots are smaller, do not movewith age or vibration, and can be recalibrated remotely. This proposed solution reduces the susceptibility of the system to thetolerance of the digital pot's end-to-end resistance, making the solution optimal fordesigners. This application note also explainssome of the equations required to calculate the resistor chain values and to use a digital pot in this way. A spreadsheet withstandard reisistor values is available for easy calculations.
Although recent popular attention is focused on LithiumIon batteries, one must not forget that other batterychemistries, such as Nickel Cadmium (NiCd) and NickelMetal Hydride (NiMH) have advantages in rechargeablepower systems. Nickel-based batteries are robust, capableof high discharge rates, have good cycle life, do notrequire special protection circuitry and are less expensivethan Li-Ion. Among the two, NiMH batteries are rapidlyreplacing NiCd Because of their higher capacity (40% to50% more) and the environmental concerns of the toxiccadmium contained in NiCd batteries.
