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  • Question

  •  

    DEAR FRIENDS EVERYONE IS INVITED TO

    POST SOME

    PAPER (INFORMATIVE OF COURSE) OR ANY NEWS      WHICH YOU LIKE TO SHARE HERE

    IN THIS THREAD AND IF THERE IS CONTENT IN YOUR PAPER IS MARKED AS "ANSWER"

    I AM STARTING HERE WITH THE FIRST PAPER BELOW:

    Sunday, March 25, 2007 9:15 AM

Answers

  •  

    Overview

     

     

    A hybrid drive is a new type of large-buffer computer hard disk drive. It is different from standard hard drives in that it employs a large buffer (up to 1 GB) of non-volatile flash memory to cache data during normal use. By primarily using this large buffer for non-volatile data storage, the platters of the hard drive are at rest almost all of the time, instead of constantly spinning as they are in current hard drives. This offers numerous benefits, chief among them speed,[1] decreased power consumption, improved reliability, and a faster boot process.

    Hybrid drives are set to be released, primarily for notebook computers, in early 2007, with Samsung introducing their first drives in January, and Seagate in the first three months. At the moment, they are only known to be fully compatible with the Windows Vista operating system[2]; Microsoft uses the name ReadyDrive to describe the software side of this technology.

    The command interface will be standardized in the new revision 8 of the ATA standard

    Function explanation

     

     

    Unlike most standard hard drives, the hybrid drive in its normal state has its platters at rest, as if it were off. During this time, any data that the user must write to the hard drive is written instead to the buffer. While working on a text document, for example, or browsing through the Internet, any temporary save files or the browser's disk cache will be saved to the buffer, instead of being written to the hard drive every time.

     

    The hybrid drive's platters will spin up in only two situations. When the buffer begins to near its capacity, the platters of the hard drive will spin up, and all of the data in the buffer will be cleared onto the hard drive, whereupon the platters will again return to an off state, and the cache will be empty for use again. The second instance is when the user must access a new file from the hard drive that is not already stored in the buffer. In this case, the platters must spin up to access the file and place it onto the buffer, whereupon the platters will once again return to an off state.[citation needed]

     

    Because the hybrid drive utilizes nonvolatile flash memory (such as those in a USB key), as opposed to volatile memory (such as RAM), the buffer is able to retain all the data even in the event of a sudden power failure or reboot, and can even store boot-up data into the buffer (see below).

     

    Early estimates place the actual hard drive usage (when the platters are spinning) at anywhere between 1.25%[3] and 10%[4] for normal users, although there are obviously situations where hard drive usage will be much higher, such as the encoding or editing of very large video files. See flash memory for more disadvantages.

     

     

     

     

    Benefits

     

     

    The hybrid drive is claimed to offer several benefits over the standard hard drive, especially for use in notebook computers.

     

    Decreased Power Consumption: Because the platters will almost always be in an off state, power consumption by the hard drive will be reduced. Although not so much of an issue for desktop computers, this greatly extends the battery life of notebook computers.

    Decreased Heat Generation: The reduced spinning of the platters also greatly decreases the amount of heat generated, as few parts of the hard drive are physically moving (and generating friction).

    Decreased Noise Levels: In addition to the decrease in noise due to needing less overall cooling because of decreased power consumption and heat generation, hybrid drives are almost completely silent due the decreased use of the hard drive platters.

    Improved Reliability: As the platters won't be spinning nearly as much, the wear and tear on the hard drive is drastically reduced. Hybrid drives should be able to last much longer than today's standard notebook drives. In addition to this, head crashes — in which a sudden movement, such as a violent impact, causes the read/write head of the hard drive to physically impact one of the platters — will become much less frequent, as the head should be docked most of the time.[verification needed]

     

     

     

    Drawbacks

     

     

    There are also drawbacks to the use of hybrid drives:

     

    Increased seek time for non-cached data: If the data being accessed is not in the cache and the drive has spun down, seek time will be greatly increased since the platters will need to spin up again.

    Increased Cost: Flash memory chips are much more expensive per-gigabyte than comparably-sized traditional hard drives.

    Increased frequency of spin-up: a hard drive, once spinning, suffers almost no wear. A significant proportion of wear arises during the spin-up and spin-down processes. A hybrid drive requires spin-up and spin-down more often than a normal hard drive, which is often spinning without a break.[citation needed]

    Disk spinup is also the time when HDD uses the most power.

    Two other potential issues arise with regards to flash memory:

     

    Lower reliable lifetime - Flash based memory has relatively limited read/write cycles compared to hard drives which can last over a decade without mechanical malfunction. This is significant since in many systems, the hard drive may regularly be accessed tens of thousands of times within even short periods.

    Lower recoverability - After failure any data in flash memory is completely lost as the cell is destroyed, while if normal HDD suffers mechanical failure the data is often recoverable using expert help. The amount of data lost if the cache of a hybrid drive is lost may be significant due to the cache size compared to the cache on non-hybrid drives.

     


     

    Sunday, March 25, 2007 9:17 AM
  • OVERVIEW of GPRS

     

     

                General Packet Radio Service (GPRS) is a mobile data service available to users of GSM and IS-136 mobile phones. GPRS data transfer is typically charged per megabyte of transferred data, while data communication via traditional circuit switching is billed per minute of connection time, independent of whether the user has actually transferred data or he has been in an idle state. GPRS can be utilized for services such as WAP access, SMS and MMS, but also for Internet communication services such as email and web access. In the future, it is expected that low cost voice over IP will be made available in cell phones.

     

    2G cellular systems combined with GPRS is often described as "2.5G", that is, a technology between the second (2G) and third (3G) generations of mobile telephony. It provides moderate speed data transfer, by using unused TDMA channels in for example the GSM system. Originally there was some thought to extend GPRS to cover other standards, but instead those networks are being converted to use the GSM standard, so that GSM is the only kind of network where GPRS is in use. GPRS is integrated into GSM standards releases starting with Release 97 and onwards. First it was standardized by ETSI but now that effort has been handed onto the 3GPP.

     

     

     

     

    GPRS basics

     

    GPRS is different from the older Circuit Switched Data (or CSD) connection included in GSM standards. In CSD, a data connection establishes a circuit, and reserves the full bandwidth of that circuit during the lifetime of the connection. GPRS is packet-switched which means that multiple users share the same transmission channel, only transmitting when they have data to send. This means that the total available bandwidth can be immediately dedicated to those users who are actually sending at any given moment, providing higher utilisation where users only send or receive data intermittently. Web browsing, receiving e-mails as they arrive and instant messaging are examples of uses that require intermittent data transfers, which benefit from sharing the available bandwidth.

     

    Usually, GPRS data are billed per kilobytes of information transceived while circuit-switched data connections are billed per second. The latter is to reflect the fact that even during times when no data are being transferred, the bandwidth is unavailable to other potential users.

     

    The multiple access methods used in GSM with GPRS are based on frequency division duplex (FDD) and FDMA. During a session, a user is assigned to one pair of uplink and downlink frequency channels. This is combined with time domain statistical multiplexing, i.e. packet mode communication, which makes it possible for several users to share the same frequency channel. The packets have constant length, corresponding to a GSM time slot. In the downlink, first-come first-served packet scheduling is used. In the uplink, a scheme that is very similar to reservation ALOHA is used. This means that slotted Aloha (S-ALOHA) is used for reservation inquiries during a contention phase, and then the actual data is transferred using first-come first-served scheduling.

     

    GPRS originally supported (in theory) IP, PPP and X.25 connections. The last has been typically used for applications like wireless payment terminals although it has been removed as a requirement from the standard. X.25 can still be supported over PPP, or even over IP, but doing this requires either a router to do encapsulation or intelligence built into the end terminal. In practice, mainly IPv4 is used. PPP is often not supported by the operator, while IPv6 is not yet popular.

     

    GPRS in practice

     

     

    Telephone operators have priced GPRS relatively cheaply (compared to older GSM data transfer, CSD and HSCSD) in many areas, such as Finland. Some mobile phone operators offer flat rate access to the Internet and some other mobile phone operators base their tariffs on data transferred, usually rounded off per 100 kilobyte.

     

    During its heyday, the mid 2000's, typical rates for GPRS service varied wildly, ranging from EUR €0,24 per megabyte to over €20 per megabyte.

     

    The maximum speed of a GPRS connection (as offered in 2003) is the same as modem connection in an analog wire telephone network, about 32–40 kbit/s (depending on the phone used). Latency is very high; a round-trip ping being typically about 600–700 ms and often reaching one second round trip time. GPRS is typically prioritized lower than speech, and thus the quality of connection varies greatly.

     

    In order to set up a GPRS connection for a wireless modem, a user needs to specify Access Point Name (APN), optionally a user name and password, and very rarely an IP address, all provided by the network operator.

     

    Devices with latency /RTT improvements (via e.g. the extended UL TBF mode feature) are rather widely available. Also network upgrades the feature(s) are available within certain operators. With these enhancements the active RTT can be reduced, resulting in significant increase in application-level throuhput speeds.

     

    Sunday, March 25, 2007 9:18 AM
  • Nokia released the N95 mobile phone, its first phone with an onboard global positioning system. The unit, which is currently available in Asia and Europe, also comes with a 5 megapixel camera that supports 30 frames-per-second video. The $732 device includes maps for 150 cities worldwide.


    Nokia (NYSE: NOK)  has started shipping its first phone with built-in GPS  (global positioning system) capabilities and a host of other applications.

    The Finnish company said the N95 mobile phone, now available in Europe and Asia, is a slider-type device with a 5 megapixel camera for shooting photos and 30 frames-per-second video.

    However, the feature that has techies in a tizzy is the built-in GPS, which allows users to find out their location, get directions, and search for nearby hotels, restaurants and other services.

     
    The Big Prize
    The device also comes with 150 maps installed for cities around the world. Programs sold separately include city guides and audio tours.

    Nokia is one of the first major handset makers to include GPS.

    "This is one of those all-in-one products that competes with a number of devices," Rob Enderle, a principal analyst with the Enderle Group, told TechNewsWorld. "It competes with the BlackBerry , portable GPS devices and other high-end phones."

    The myriad of functions in the new phone should be able to keep up with its counterparts sold individually, Enderle also noted.

    In addition to the key features, the phone has a 2.6 inch TFT (thin film transistor) display with 240 by 320 pixel screen resolution, and a MicroSD memory card slot, according to the company.

    In fact, it packs so many extras that Nokia is calling it a "multimedia computer."

    "It easily replaces a number of single purpose devices with a well designed package that is with you and connected," Juha Putkiranta, senior vice president at Nokia, said.

    All the bells and whistles also help ring up a higher price on the phone. At US$732, it is one of the priciest additions to Nokia's Nseries range.

    "There is definitely a market for it," said Enderle. "There are plenty of products that are in the incredible nosebleed category [in terms of costs] that people are lining up for. This type of premium product should do very well."

    The OS and More
    The phone operates on HSDPA (high speed downlink packet access) networks, wireless LANs, EDGE and WCDMA networks, and is based on Nokia's S60 software and the Symbian  OS, according to the company.

    Nokia acquired the technology when it bought Gate5 last year.

    The handset also includes RealNetworks' (Nasdaq: RNWK)  RealPlayer, Nokia's PC Suite with a calendar and e-mail , and software for posting to blogs and to the Flickr.com photo site.

    The device can connect to a PC via Bluetooth , USB  2.0 or a wireless LAN, so users can download music and video to the device to play later

    refference :technonews.com

    Sunday, March 25, 2007 9:19 AM
  • MPEG-1 Audio Layer 3, more commonly referred to as MP3, is a popular digital audio encoding, lossy compression format, and algorithm, designed to greatly reduce the amount of data required to represent audio, yet still sound like a faithful reproduction of the original uncompressed audio to most listeners. It was invented by a team of European engineers of Philips, CCETT (Centre commun d'études de télévision et télécommunications), IRT and Fraunhofer Society, who worked in the framework of the EUREKA 147 DAB digital radio research program, and it became an ISO/IEC standard in 1991.

    encoding

     

    The MPEG-1 standard does not include a precise specification for an MP3 encoder. The decoding algorithm and file format, as a contrast, are well defined. Implementers of the standard were supposed to devise their own algorithms suitable for removing parts of the information in the raw audio (or rather its MDCT representation in the frequency domain). During encoding 576 time domain samples are taken and are transformed to 576 frequency domain samples. If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)

    As a result, there are many different MP3 encoders available, each producing files of differing quality. Comparisons are widely available, so it is easy for a prospective user of an encoder to research the best choice. It must be kept in mind that an encoder that is proficient at encoding at higher bit rates (such as LAME, which is in widespread use for encoding at higher bit rates) is not necessarily as good at other, lower bit rates.

     

    decoding

    Decoding, on the other hand, is carefully defined in the standard. Most decoders are "bitstream compliant", meaning that the decompressed output they produce from a given MP3 file will be the same (within a specified degree of rounding tolerance) as the output specified mathematically in the ISO/IEC standard document. The MP3 file has a standard format which is a frame consisting of 384, 576, or 1152 samples (depends on MPEG version and layer) and all the frames have associated header information (32 bits) and side information (9, 17, or 32 bytes, depending on MPEG version and stereo/mono). The header and side information help the decoder to decode the associated Huffman encoded data correctly.

    Therefore, comparison of decoders is usually based on how computationally efficient they are (i.e., how much memory or CPU time they use in the decoding process).

    BIT RATE

     

    [edit] Bit rate
    Several bit rates are specified in the MPEG-1 Layer 3 standard: 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s, and the available sampling frequencies are 32, 44.1 and 48 kHz. A sample rate of 44.1 kHz is almost always used since this is also used for CD audio, the main source used for creating MP3 files. A greater variety of bitrates are used on the internet. 128 kbit/s is the most common since it typically offers very good audio quality in a relatively small space. 192 kbit/s is often used by those who notice artifacts at lower bitrates. By contrast, uncompressed audio as stored on a compact disc has a bit rate of 1411.2 kb/s (16 bits/sample × 44100 samples/second × 2 channels).

    Some additional bit rates and sample rates were made available in the MPEG-2 and the (unofficial) MPEG-2.5 standards: bit rates of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kb/s and sample rates of 8, 11.025, 12, 16, 22.05 and 24 kHz.

    Non-standard bit rates up to 640 kb/s can be achieved with the LAME encoder and the --freeformat option, but few MP3 players can play those files. Gabriel Bouvigne, a principal developer of the LAME project, says that the freeformat option is compliant with the standard but, according to the standard, decoders are only required to be able to decode streams up to 320 kbit/s


     

    Sunday, March 25, 2007 9:20 AM

All replies

  •  

    Overview

     

     

    A hybrid drive is a new type of large-buffer computer hard disk drive. It is different from standard hard drives in that it employs a large buffer (up to 1 GB) of non-volatile flash memory to cache data during normal use. By primarily using this large buffer for non-volatile data storage, the platters of the hard drive are at rest almost all of the time, instead of constantly spinning as they are in current hard drives. This offers numerous benefits, chief among them speed,[1] decreased power consumption, improved reliability, and a faster boot process.

    Hybrid drives are set to be released, primarily for notebook computers, in early 2007, with Samsung introducing their first drives in January, and Seagate in the first three months. At the moment, they are only known to be fully compatible with the Windows Vista operating system[2]; Microsoft uses the name ReadyDrive to describe the software side of this technology.

    The command interface will be standardized in the new revision 8 of the ATA standard

    Function explanation

     

     

    Unlike most standard hard drives, the hybrid drive in its normal state has its platters at rest, as if it were off. During this time, any data that the user must write to the hard drive is written instead to the buffer. While working on a text document, for example, or browsing through the Internet, any temporary save files or the browser's disk cache will be saved to the buffer, instead of being written to the hard drive every time.

     

    The hybrid drive's platters will spin up in only two situations. When the buffer begins to near its capacity, the platters of the hard drive will spin up, and all of the data in the buffer will be cleared onto the hard drive, whereupon the platters will again return to an off state, and the cache will be empty for use again. The second instance is when the user must access a new file from the hard drive that is not already stored in the buffer. In this case, the platters must spin up to access the file and place it onto the buffer, whereupon the platters will once again return to an off state.[citation needed]

     

    Because the hybrid drive utilizes nonvolatile flash memory (such as those in a USB key), as opposed to volatile memory (such as RAM), the buffer is able to retain all the data even in the event of a sudden power failure or reboot, and can even store boot-up data into the buffer (see below).

     

    Early estimates place the actual hard drive usage (when the platters are spinning) at anywhere between 1.25%[3] and 10%[4] for normal users, although there are obviously situations where hard drive usage will be much higher, such as the encoding or editing of very large video files. See flash memory for more disadvantages.

     

     

     

     

    Benefits

     

     

    The hybrid drive is claimed to offer several benefits over the standard hard drive, especially for use in notebook computers.

     

    Decreased Power Consumption: Because the platters will almost always be in an off state, power consumption by the hard drive will be reduced. Although not so much of an issue for desktop computers, this greatly extends the battery life of notebook computers.

    Decreased Heat Generation: The reduced spinning of the platters also greatly decreases the amount of heat generated, as few parts of the hard drive are physically moving (and generating friction).

    Decreased Noise Levels: In addition to the decrease in noise due to needing less overall cooling because of decreased power consumption and heat generation, hybrid drives are almost completely silent due the decreased use of the hard drive platters.

    Improved Reliability: As the platters won't be spinning nearly as much, the wear and tear on the hard drive is drastically reduced. Hybrid drives should be able to last much longer than today's standard notebook drives. In addition to this, head crashes — in which a sudden movement, such as a violent impact, causes the read/write head of the hard drive to physically impact one of the platters — will become much less frequent, as the head should be docked most of the time.[verification needed]

     

     

     

    Drawbacks

     

     

    There are also drawbacks to the use of hybrid drives:

     

    Increased seek time for non-cached data: If the data being accessed is not in the cache and the drive has spun down, seek time will be greatly increased since the platters will need to spin up again.

    Increased Cost: Flash memory chips are much more expensive per-gigabyte than comparably-sized traditional hard drives.

    Increased frequency of spin-up: a hard drive, once spinning, suffers almost no wear. A significant proportion of wear arises during the spin-up and spin-down processes. A hybrid drive requires spin-up and spin-down more often than a normal hard drive, which is often spinning without a break.[citation needed]

    Disk spinup is also the time when HDD uses the most power.

    Two other potential issues arise with regards to flash memory:

     

    Lower reliable lifetime - Flash based memory has relatively limited read/write cycles compared to hard drives which can last over a decade without mechanical malfunction. This is significant since in many systems, the hard drive may regularly be accessed tens of thousands of times within even short periods.

    Lower recoverability - After failure any data in flash memory is completely lost as the cell is destroyed, while if normal HDD suffers mechanical failure the data is often recoverable using expert help. The amount of data lost if the cache of a hybrid drive is lost may be significant due to the cache size compared to the cache on non-hybrid drives.

     


     

    Sunday, March 25, 2007 9:17 AM
  • OVERVIEW of GPRS

     

     

                General Packet Radio Service (GPRS) is a mobile data service available to users of GSM and IS-136 mobile phones. GPRS data transfer is typically charged per megabyte of transferred data, while data communication via traditional circuit switching is billed per minute of connection time, independent of whether the user has actually transferred data or he has been in an idle state. GPRS can be utilized for services such as WAP access, SMS and MMS, but also for Internet communication services such as email and web access. In the future, it is expected that low cost voice over IP will be made available in cell phones.

     

    2G cellular systems combined with GPRS is often described as "2.5G", that is, a technology between the second (2G) and third (3G) generations of mobile telephony. It provides moderate speed data transfer, by using unused TDMA channels in for example the GSM system. Originally there was some thought to extend GPRS to cover other standards, but instead those networks are being converted to use the GSM standard, so that GSM is the only kind of network where GPRS is in use. GPRS is integrated into GSM standards releases starting with Release 97 and onwards. First it was standardized by ETSI but now that effort has been handed onto the 3GPP.

     

     

     

     

    GPRS basics

     

    GPRS is different from the older Circuit Switched Data (or CSD) connection included in GSM standards. In CSD, a data connection establishes a circuit, and reserves the full bandwidth of that circuit during the lifetime of the connection. GPRS is packet-switched which means that multiple users share the same transmission channel, only transmitting when they have data to send. This means that the total available bandwidth can be immediately dedicated to those users who are actually sending at any given moment, providing higher utilisation where users only send or receive data intermittently. Web browsing, receiving e-mails as they arrive and instant messaging are examples of uses that require intermittent data transfers, which benefit from sharing the available bandwidth.

     

    Usually, GPRS data are billed per kilobytes of information transceived while circuit-switched data connections are billed per second. The latter is to reflect the fact that even during times when no data are being transferred, the bandwidth is unavailable to other potential users.

     

    The multiple access methods used in GSM with GPRS are based on frequency division duplex (FDD) and FDMA. During a session, a user is assigned to one pair of uplink and downlink frequency channels. This is combined with time domain statistical multiplexing, i.e. packet mode communication, which makes it possible for several users to share the same frequency channel. The packets have constant length, corresponding to a GSM time slot. In the downlink, first-come first-served packet scheduling is used. In the uplink, a scheme that is very similar to reservation ALOHA is used. This means that slotted Aloha (S-ALOHA) is used for reservation inquiries during a contention phase, and then the actual data is transferred using first-come first-served scheduling.

     

    GPRS originally supported (in theory) IP, PPP and X.25 connections. The last has been typically used for applications like wireless payment terminals although it has been removed as a requirement from the standard. X.25 can still be supported over PPP, or even over IP, but doing this requires either a router to do encapsulation or intelligence built into the end terminal. In practice, mainly IPv4 is used. PPP is often not supported by the operator, while IPv6 is not yet popular.

     

    GPRS in practice

     

     

    Telephone operators have priced GPRS relatively cheaply (compared to older GSM data transfer, CSD and HSCSD) in many areas, such as Finland. Some mobile phone operators offer flat rate access to the Internet and some other mobile phone operators base their tariffs on data transferred, usually rounded off per 100 kilobyte.

     

    During its heyday, the mid 2000's, typical rates for GPRS service varied wildly, ranging from EUR €0,24 per megabyte to over €20 per megabyte.

     

    The maximum speed of a GPRS connection (as offered in 2003) is the same as modem connection in an analog wire telephone network, about 32–40 kbit/s (depending on the phone used). Latency is very high; a round-trip ping being typically about 600–700 ms and often reaching one second round trip time. GPRS is typically prioritized lower than speech, and thus the quality of connection varies greatly.

     

    In order to set up a GPRS connection for a wireless modem, a user needs to specify Access Point Name (APN), optionally a user name and password, and very rarely an IP address, all provided by the network operator.

     

    Devices with latency /RTT improvements (via e.g. the extended UL TBF mode feature) are rather widely available. Also network upgrades the feature(s) are available within certain operators. With these enhancements the active RTT can be reduced, resulting in significant increase in application-level throuhput speeds.

     

    Sunday, March 25, 2007 9:18 AM
  • Nokia released the N95 mobile phone, its first phone with an onboard global positioning system. The unit, which is currently available in Asia and Europe, also comes with a 5 megapixel camera that supports 30 frames-per-second video. The $732 device includes maps for 150 cities worldwide.


    Nokia (NYSE: NOK)  has started shipping its first phone with built-in GPS  (global positioning system) capabilities and a host of other applications.

    The Finnish company said the N95 mobile phone, now available in Europe and Asia, is a slider-type device with a 5 megapixel camera for shooting photos and 30 frames-per-second video.

    However, the feature that has techies in a tizzy is the built-in GPS, which allows users to find out their location, get directions, and search for nearby hotels, restaurants and other services.

     
    The Big Prize
    The device also comes with 150 maps installed for cities around the world. Programs sold separately include city guides and audio tours.

    Nokia is one of the first major handset makers to include GPS.

    "This is one of those all-in-one products that competes with a number of devices," Rob Enderle, a principal analyst with the Enderle Group, told TechNewsWorld. "It competes with the BlackBerry , portable GPS devices and other high-end phones."

    The myriad of functions in the new phone should be able to keep up with its counterparts sold individually, Enderle also noted.

    In addition to the key features, the phone has a 2.6 inch TFT (thin film transistor) display with 240 by 320 pixel screen resolution, and a MicroSD memory card slot, according to the company.

    In fact, it packs so many extras that Nokia is calling it a "multimedia computer."

    "It easily replaces a number of single purpose devices with a well designed package that is with you and connected," Juha Putkiranta, senior vice president at Nokia, said.

    All the bells and whistles also help ring up a higher price on the phone. At US$732, it is one of the priciest additions to Nokia's Nseries range.

    "There is definitely a market for it," said Enderle. "There are plenty of products that are in the incredible nosebleed category [in terms of costs] that people are lining up for. This type of premium product should do very well."

    The OS and More
    The phone operates on HSDPA (high speed downlink packet access) networks, wireless LANs, EDGE and WCDMA networks, and is based on Nokia's S60 software and the Symbian  OS, according to the company.

    Nokia acquired the technology when it bought Gate5 last year.

    The handset also includes RealNetworks' (Nasdaq: RNWK)  RealPlayer, Nokia's PC Suite with a calendar and e-mail , and software for posting to blogs and to the Flickr.com photo site.

    The device can connect to a PC via Bluetooth , USB  2.0 or a wireless LAN, so users can download music and video to the device to play later

    refference :technonews.com

    Sunday, March 25, 2007 9:19 AM
  • MPEG-1 Audio Layer 3, more commonly referred to as MP3, is a popular digital audio encoding, lossy compression format, and algorithm, designed to greatly reduce the amount of data required to represent audio, yet still sound like a faithful reproduction of the original uncompressed audio to most listeners. It was invented by a team of European engineers of Philips, CCETT (Centre commun d'études de télévision et télécommunications), IRT and Fraunhofer Society, who worked in the framework of the EUREKA 147 DAB digital radio research program, and it became an ISO/IEC standard in 1991.

    encoding

     

    The MPEG-1 standard does not include a precise specification for an MP3 encoder. The decoding algorithm and file format, as a contrast, are well defined. Implementers of the standard were supposed to devise their own algorithms suitable for removing parts of the information in the raw audio (or rather its MDCT representation in the frequency domain). During encoding 576 time domain samples are taken and are transformed to 576 frequency domain samples. If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)

    As a result, there are many different MP3 encoders available, each producing files of differing quality. Comparisons are widely available, so it is easy for a prospective user of an encoder to research the best choice. It must be kept in mind that an encoder that is proficient at encoding at higher bit rates (such as LAME, which is in widespread use for encoding at higher bit rates) is not necessarily as good at other, lower bit rates.

     

    decoding

    Decoding, on the other hand, is carefully defined in the standard. Most decoders are "bitstream compliant", meaning that the decompressed output they produce from a given MP3 file will be the same (within a specified degree of rounding tolerance) as the output specified mathematically in the ISO/IEC standard document. The MP3 file has a standard format which is a frame consisting of 384, 576, or 1152 samples (depends on MPEG version and layer) and all the frames have associated header information (32 bits) and side information (9, 17, or 32 bytes, depending on MPEG version and stereo/mono). The header and side information help the decoder to decode the associated Huffman encoded data correctly.

    Therefore, comparison of decoders is usually based on how computationally efficient they are (i.e., how much memory or CPU time they use in the decoding process).

    BIT RATE

     

    [edit] Bit rate
    Several bit rates are specified in the MPEG-1 Layer 3 standard: 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s, and the available sampling frequencies are 32, 44.1 and 48 kHz. A sample rate of 44.1 kHz is almost always used since this is also used for CD audio, the main source used for creating MP3 files. A greater variety of bitrates are used on the internet. 128 kbit/s is the most common since it typically offers very good audio quality in a relatively small space. 192 kbit/s is often used by those who notice artifacts at lower bitrates. By contrast, uncompressed audio as stored on a compact disc has a bit rate of 1411.2 kb/s (16 bits/sample × 44100 samples/second × 2 channels).

    Some additional bit rates and sample rates were made available in the MPEG-2 and the (unofficial) MPEG-2.5 standards: bit rates of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kb/s and sample rates of 8, 11.025, 12, 16, 22.05 and 24 kHz.

    Non-standard bit rates up to 640 kb/s can be achieved with the LAME encoder and the --freeformat option, but few MP3 players can play those files. Gabriel Bouvigne, a principal developer of the LAME project, says that the freeformat option is compliant with the standard but, according to the standard, decoders are only required to be able to decode streams up to 320 kbit/s


     

    Sunday, March 25, 2007 9:20 AM
  • its good to see this
    Friday, March 30, 2007 3:16 PM