Friday, February 13, 2015

HTAM - Intel’s Hyper-Threading Technology


Intel’s Hyper-Threading Technology brings the concept of simultaneous multi-threading to the Intel Architecture. Hyper-Threading Technology makes a single physical processor appear as two logical processors; the physical execution resources are shared and the architecture state is duplicated for the two logical processors. From a software or architecture perspective, this means operating systems and user programs can schedule processes or threads to logical processors as they would on multiple physical processors. From a micro architecture perspective, this means that instructions from both logical processors will persist and execute simultaneously on shared execution resources.

Hyper-Threading Technology makes a single physical processor appear as multiple logical processors [11, 12]. To do this, there is one copy of the architecture state for each logical processor, and the logical processors share a single set of physical execution resources. From a software or architecture perspective, this means operating systems and user programs can schedule processes or threads to logical processors as they would on conventional physical processors in a multiprocessor system. From a micro-architecture perspective, this means that instructions from logical processors will persist and execute simultaneously on shared execution resources.

The first implementation of Hyper-Threading Technology is being made available on the Intel. Xeon processor family for dual and multiprocessor servers, with two logical processors per physical processor. By more efficiently using existing processor resources, the Intel Xeon processor family can significantly improve performance at virtually the same system cost. This implementation of Hyper-Threading Technology added less than 5% to the relative chip size and maximum power requirements, but can provide performance benefits much greater than that.

Each logical processor maintains a complete set of the architecture state. The architecture state consists of registers including the general-purpose registers, the control registers, the advanced programmable interrupt controller (APIC) registers, and some machine state registers. From a software perspective, once the architecture state is duplicated, the processor appears to be two processors. The number of transistors to store the architecture state is
an extremely small fraction of the total. Logical processors share nearly all other resources on the physical processor, such as caches, execution units, branch predictors, control logic, and buses. Each logical processor has its own interrupt controller or APIC. Interrupts sent to a specific logical only that logical processor handles processors.


  • High processor utilization rates: One processor with two architectural states enable the processor to more efficiently utilize execution resources. Because the two threads share one set of execution resources, the second thread can use resources that would be otherwise idle if only one thread was executing. The result is an increased utilization of the execution resources within each physical processor package.
  • Higher performance for properly optimized software: Greater throughput is achieved when software is multithreaded in a way that allows different threads to tap different processor resources in parallel. For example, Integer operations are scheduled on one logical processor while floating point computations occur on the other.
  • Full backward compatibility: Virtually all multiprocessor-aware operating systems and multithreaded applications benefit from Hyper- Threading technology. Software that lacks multiprocessor capability is unaffected by Hyper-Threading technology.

Image Source: Wikimedia

Bacterio-Rhodopsin Memory

At first, it was sufficient to paint on the family cave wall how one hunted. Since the dawn of time, man has tried to record important events and techniques for everyday life. Then came the people who invented spoken languages and the need arose to record what one was saying without hearing it firsthand. Therefore later, more early scholars invented writing to convey what was being said. Pictures gave way to letters that represented spoken sounds. Eventually clay tablets gave way to parchment, which gave way to paper. Paper was, and still is, the main way people convey information.

However, in the mid twentieth century computers began to come into general use . . .
Computers have gone through their own evolution in storage media. In the forties, fifties, and sixties, everyone who took a computer course used punched cards to give the computer information and store data. In 1956, researchers at IBM developed the first disk storage system. This was called RAMAC (Random Access Method of Accounting and Control).


Since the days of punch cards, computer manufacturers have strived to squeeze more data into smaller spaces. That mission has produced both competing and complementary data storage technology including electronic circuits, magnetic media like hard disks and tape, and optical media such as compact disks.
The demands made upon computers and computing devices are increasing each year. Processor speeds are increasing at an extremely fast clip. However, the RAM used in most computers is the same type of memory used several years ago. The limits of making RAM denser are being reached. Surprisingly, these limits may be economical rather than physical. A decrease by a factor of two in size will increase the cost of manufacturing of semiconductor pieces by a factor of 5.

Currently, RAM is available in modules called SIMMs or DIMMs. These modules can be bought in various capacities from a few hundred kilobytes of RAM to about 64 megabytes. Anything more is both expensive and rare. These modules are generally 70ns, however 60ns and 100ns modules are available. The lower the nanosecond rating, the more the module will cost.
Currently, a 64MB DIMM costs over $400.
All dimensions are 12cm by 3cm by 1cm or about 36 cubic centimeters. Whereas a 5 cubic centimeter block of bacterio-rhodopsin studded polymer could theoretically store 512 gigabytes of information. When this comparison is made, the advantage becomes quite clear. Also, these bacterio-rhodopsin modules could also theoretically run 1000 times faster.

In response to the demand for faster, more compact, and more affordable memory storage devices, several viable alternatives have appeared in recent years. Among the most promising approaches include memory storage using holography, polymer-based memory, and our focus, protein-based memory.

The bacterio-rhodopsin protein is one of the most promising organic memory materials. Seven helix-shaped polymers form a membrane structure, which contains a molecule known as the retinal chromophor. The chromophor absorbs light of a certain color and is therefore able to switch to another stable state in addition to its original state. Only blue light can change the molecule back to its original state. 

There have been many methods and proteins researched for use in computer applications in recent years. However, among the most promising approaches, and the focus of this particular web page, is 3-Dimensional Optical RAM storage using the light sensitive protein bacterio-rhodopsin. Bacterio-rhodopsin is a protein found in the purple membranes of several species of bacteria, most notably Halobacterium halobium. This particular bacteria lives in salt marshes. Salt marshes have very high salinity and temperatures can reach 140 degrees Fahrenheit. Unlike most proteins, bacterio-rhodopsin does not break down at these high temperatures.

Early research in the field of protein-based memories yielded some serious problems with using proteins for practical computer applications. Among the most serious of the problems was the instability and unreliable nature of proteins, which are subject to thermal and photochemical degradation, making room-temperature or higher-temperature use impossible. Largely through trial and error, and thanks in part to nature's own natural selection process, scientists stumbled upon bacterio-rhodopsin, a light-harvesting protein that has certain properties which makes it a prime candidate for computer applications. While bacterio-rhodopsin can be used in any number of schemes to store memory, we will focus our attention on the use of bacterio-rhodopsin in 3-Dimensional Optical Memories.

Image Source: Wikipedia, Extremetech

What is xMax


xMax, as a physical layer technology, can be configured for use in wired and wireless products; designed for deployment at any frequency; configured for licensed and unlicensed spectrum, or in a spectrum sharing fashion. Importantly, it can improve range and battery life in such applications and uses the radio spectrum in a very power efficient manner. The original xMax system is a hybrid technology in the sense that it has aspects of both narrowband and wideband communication systems; it uses pulse position modulation (PPM) and ultra wideband communications (UWB), but also employs a narrowband carrier. The use of the carrier at the receiver basically eliminates the difficult synchronization and search problems inherent with PPM and UWB systems.

The GSM Association estimates that of the 4B mobile users worldwide, roughly 90% are voice only users
Thus we see that despite the hype, mobile broadband data revenues are less than 20% of that of mobile voice. Even using bullish industry assumptions for mobile broadband data growth, it is likely to take 9-10 years before mobile broadband data revenues are on parity with mobile voice revenues.

Low-cost mobile voice and broadband data services, xG Technology, Inc. has developed an innovative wireless communication system (aka “xMax”) that is capable of delivering mobile voice over IP (VoIP) and broadband data services in the 902-928 MHz unlicensed band. From a business model perspective xG Technology is targeting this scalable radio access network (RAN) solution towards new-entrant service provider partners, such as cable companies, competitive local exchange carriers (CLECs), satellite companies, foreign incumbent local exchange carriers, etc. that may be seeking to deliver mobile VoIP/data services to the market on a nationwide or selected market basis.

The inclusion of voice capability in addition to broadband data in the xMax RAN solution is a critical differentiation that will be emphasized throughout this white paper. This is because despite the media fascination with the iPhone™ and other smartphones and despite the increasing demand for mobile broadband data services, mobile voice remains and will continue to remain the major revenue earner for mobile operators. Note the following market facts:


xMax is a mobile voice and data solution from xG Technology that has been designed to address the issues raised above and more. In particular, it was designed with the following requirements in mind:

  • A single end-to-end IP network architecture supporting mobile voice, wideband data, real time video, chat and other apps.
  • Dynamic Spectrum Access (DSA) and advanced interference mitigation to increase operational and deployment flexibility.
  • Leverages COTS end user devices including 3G and 4G smart phones, tablets and net books without requiring licensed commercial frequencies. 
  • Full cognitive networking capabilities including dynamic access and optimization of available spectrum resources, as well as self-Radio Frequency (RF) planning and self-organizing. 


Take the energy issue first. xMax uses a modulation technique designed to allow more data to be transmitted on a single sine waves than is required with typical modulation technologies. So instead of using more than 100,000 sine waves to transmit one bit of data, xMax uses a ratio closer to 1:1. This technique would therefore be more efficient and keep energy levels very low, which would mean devices that receive the signals wouldn't consume much power. To solve the distance problem, xMax uses frequency channels in the sub-gigahertz range, which can penetrate obstacles such as walls or trees. But channels below 1GHz are very narrow, which means it is difficult to pack large amounts of data into them. xMax fulfills the need for a radio technology that According to the inventor Joseph Bobier "xMax's unique signal profile is a perfect fit for low frequency channels that have previously been unsuitable for wireless broadband." The technology will benefit rural ISPs due to the lower number of base stations required. xMax, because it has 20 times the range of Bluetooth, could challenge that technology. Other possibilities are enterprise WLANs and metropolitan networks. Nowadays it is used for VoIP (Voice over Internet Protocol)

Network Structure

In order to meet the objective of providing low-cost mobile voice and broadband data services the xMax carrier class cognitive radio solution has been developed around commonly used and open Internet protocols including IP, RTP, UDP and IP. In addition, it was designed to operate in both unlicensed spectrum, such as the 902-928 MHz ISM band, and licensed spectrum.

As a result of these design considerations, xMax includes responsive opportunistic-use technology based on “Identify And Utilize (IAU) techniques capable of combating in-band interference encountered in the unlicensed spectrum, and extends the SIP and RTP protocols to the wireless domain.

Among VoIP signaling protocols, SIP is regarded as very bandwidth-inefficient from a signaling overhead standpoint. In fact, SIP signaling can consume up to 400% of the VoIP payload bandwidth, an unacceptable figure for mobile networks.

Friday, January 2, 2015

DARPA Developed Mind Controlled Artificial Arm

DARPA has recently developed a Technological Surprise

DARPA Director, Arati Prabhakar spoke about the projects the agency is currently funding, including a mind-controlled robotic arm, at Expand NY. Tested by Jan Scheuermann, the test run has ended.  However, the University of Pittsburgh has recently published a paper explaining how the limb has improved over the past two years.  “Overall, our results indicate that highly coordinated, natural movement can be restored to people whose arms and hands are paralyzed,” said Pitt School of Medicine professor Andrew Schwartz, Ph.D.

Jan could move the arm, wrist and fingers of the robotic arm and even reportedly beat her brother in a rock, paper, scissor game. In 2012 Jan had neural implants put in the part of her brain that controls her right arm. How was this ‘mind reading’ accomplished?  Scientists had her watch animations of hand-arm movements and had her imagine doing them.  The brain patterns were then used to program the arm.

Scientists would now like to further their technology by using the arm on other volunteers.  Although it still stalls when the hand holds an object, they are hoping to fix the problem.  The aim is to make it a wireless, wheelchair device.  BrainGate is also a research company working on mind-controlled robotic limbs.  Duke University also made a mind-controlled exoskeleton for Juliana Pinto who used it during opening ceremony of the World cup in June.

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