Featured Research

from universities, journals, and other organizations

Data storage: Synchronized at the 'write time'

Date:
May 13, 2013
Source:
The Agency for Science, Technology and Research (A*STAR)
Summary:
Numerical simulations show how to avoid imperfections in the next generation of high-density data storage.

A scanning electron microscope image of a bit-patterned recording medium, with ordered arrays of magnetic islands.
Credit: 2013 A*STAR Data Storage Institute

Numerical simulations show how to avoid imperfections in the next generation of high-density data storage.

Related Articles


The rise of the internet and the move from paper to digital information has driven a need for large-volume electronic data storage. Maria Yu Lin and her co‐workers at the A*STAR Data Storage Institute, Singapore, have now established some important design principles to consider when developing bit patterned media recording (BPMR) -- a potential high-density magnetic recording system of the future.

Conventional hard disk drives store a single data bit in a continuous magnetic medium consisting of many 'grains'. However, the number (approximately 10-15) and the size of these grains (about 6-10 nanometers) naturally limits the maximum density at which digital information can be stored. The BPMR technique offers much higher storage capacity because it records the data in a regular array of single-grain magnetic islands (see image) that can be much smaller than multiple grain bits in continuous media, according to Lin.

"Multiple grains must be used per data bit in continuous-media storage," she explains. "Ideally, bit-patterned media [will] achieve one grain per bit because the magnetic cells are patterned in isolated and ordered arrays known as 'islands'."

A number of practical hurdles, however, are preventing the use of BPMR in computer hard disks. One problem is that the islands are separated by non-magnetic spaces -- some 25-65% of the surface only is magnetic. The data can be passed from the writing `head' only when it is aligned with an island on the spinning disk. Therefore the writing process must be synchronized with the position of the magnetic islands. However, manufacturing defects, variations in disk spinning speed and vibrations can all cause temporal misalignment, which in turn causes writing errors.

Adding information to the disk that tells the writing head its exact position is one way to correctly time the writing process. This includes synchronization sectors and error correction information; however, this information reduces the capacity of the disk for data storage. Lin and co-workers used computer simulations to theoretically analyze the optimum number of the synchronization sectors. They also analyzed how the additional information would relate to variations in disk spin speed. They investigated the system with read/write spindle motors suffering from high, medium, low and zero speed variation.

"The analysis indicates that the total additional information needed for synchronization and error correction for a motor with a medium rotation variation is 11.75%," says Lin. "Compared to the potential gain in terms of data density that this technology enables, such a total overhead is acceptable."

The A*STAR-affiliated researchers contributing to this research are from the Data Storage Institute


Story Source:

The above story is based on materials provided by The Agency for Science, Technology and Research (A*STAR). Note: Materials may be edited for content and length.


Journal References:

  1. Maria Yu Lin, Moulay Rachid Elidrissi, Kheong Sann Chan, Kwaku Eason, Melissa Chua, Mohamed Asbahi, Joel K. W. Yang, Naganivetha Thiyagarajah, Vivian Ng. Channel Characterization and Performance Evaluation of Bit-Patterned Media. IEEE Transactions on Magnetics, 2013; 49 (2): 723 DOI: 10.1109/TMAG.2012.2226708
  2. Maria Yu Lin, Kheong Sann Chan, Melissa Chua, Songhua Zhang, Cai Kui, Moulay Rachid Elidrissi. Modeling for write synchronization in bit patterned media recording. Journal of Applied Physics, 2012; 111 (7): 07B918 DOI: 10.1063/1.3679022

Cite This Page:

The Agency for Science, Technology and Research (A*STAR). "Data storage: Synchronized at the 'write time'." ScienceDaily. ScienceDaily, 13 May 2013. <www.sciencedaily.com/releases/2013/05/130513114955.htm>.
The Agency for Science, Technology and Research (A*STAR). (2013, May 13). Data storage: Synchronized at the 'write time'. ScienceDaily. Retrieved November 27, 2014 from www.sciencedaily.com/releases/2013/05/130513114955.htm
The Agency for Science, Technology and Research (A*STAR). "Data storage: Synchronized at the 'write time'." ScienceDaily. www.sciencedaily.com/releases/2013/05/130513114955.htm (accessed November 27, 2014).

Share This


More From ScienceDaily



More Computers & Math News

Thursday, November 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

EU Pushes Google For Worldwide Right To Be Forgotten

EU Pushes Google For Worldwide Right To Be Forgotten

Newsy (Nov. 27, 2014) Privacy regulators recommend Google expand its requested removals to apply to all its web domains. Video provided by Newsy
Powered by NewsLook.com
Predictions Of Tablets' Demise Sound Familiar

Predictions Of Tablets' Demise Sound Familiar

Newsy (Nov. 26, 2014) The tablet's days are numbered, at least according to a recent IDC report. The market-research firm paints a grim outlook for tablets. Video provided by Newsy
Powered by NewsLook.com
Today's Prostheses Are More Capable Than Ever

Today's Prostheses Are More Capable Than Ever

Newsy (Nov. 26, 2014) Advances in prosthetics are making replacement body parts stronger and more lifelike than they’ve ever been. Video provided by Newsy
Powered by NewsLook.com
FCC Forces T-Mobile To Alert Customers Of Data Throttling

FCC Forces T-Mobile To Alert Customers Of Data Throttling

Newsy (Nov. 25, 2014) T-Mobile and the FCC have reached an agreement requiring the company to alert customers when it throttles their data speeds. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins