What is Blu-Ray?

Blu-Ray is an optical storage format developed by Sony and Phillips. Blu-Ray was created to store large amounts of high definition video and sound. Blu-Ray gets its name from the type of laser it uses to read and write data from and to the disc, the color of the laser is a hue of blue-violet. Due to the extreme density of these optical discs the data needs to be smaller to fit onto the disc, a blue-violet laser has a shorter wavelength than the normal red lasers used today.

Blu-Ray technology is so-named because of its use of blue laser technology in storing and reading data. Being on the shorter wavelength end of the light spectrum than the red laser used for DVD and CD technologies (405 nanometer for Blu-Ray versus 650 nanometer and 780 nanometer for DVD and CD technology), blue laser is capable of storing a much larger amount of data using the same space because of a much smaller "spot size" requirement. Blu-Ray's 405nm wavelength blue-violet laser uses an 0.85nm pickup aperture.

Single-layer Blu-Ray disks currently store 23.3GB of data, which dual-layer Blu-Ray disks are able to store 46.6GB of data.

There is currently a market war taking place against both HD DVD's and Blu-Ray DVD's. These two types of DVD's are fighting to see who will be the new form of media for the years to come. As of yet, neither media type has made enough inroads to garner a champion.

Obviously the major benefit of Blu-Ray DVD's is that it is able to hold more data on one disc, therefore allowing high definition audio and video. The more data you have, the more data can be read to give a clearer picture with more color and vividness.

One of the benefits of Blu-Ray technology is that because data is so close together, early types of Blu-Ray discs would be contaminated by slight scratches. However, a new coating has been developed that makes Blu-Ray discs extremely difficult to scratch.

Blu-Ray is looking to make inroads into the consumer electronics market with the Blu-Ray DVD player with its Sony PlayStation. The Sony PlayStation will include a basic Blu-Ray DVD player which might spur sales of media and make it the de facto standard.

The disadvantages to Blu-Ray discs are that they are quite expensive. For instance, players are selling at about the $1,000 mark and DVD discs will be more expensive than their standard DVD counterparts. Another disadvantage is that since there are two standards, both Blu-Ray and HD, most people are sitting on the sidelines to see who the winner is. Because Blu-Ray has been developed in part with Sony, Sony has included DRM or digital rights management that will make it more difficult for people to place shift and time shift their content.

Blu-Ray Technology

BD Formats

There are three formats being developed for Blu-Ray technology. The BD-ROM or Blu-Ray read-only disc format will be used to store movies, computer games and software. The Blu-Ray recordable or BD-R will provide users the opportunity to store larger amounts of data and HDTV recordings in one disc. The BD-RE or Blu-Ray rewritable disc format will provide users the ability to change the disc's contents.

Disc Capacity

The main advantage of Blu-Ray technology is its capability of storing massive amounts of data in one disc. Blu-Ray technology will enable users to store an average of 25GB-27GB worth of data into just one layer. This is equivalent to 4 hours worth of HD video and audio. Moreover, Blu-Ray dual layer discs will have a storage capacity of up to 54GB. Research on Blu-Ray discs with up to four layers and with storage capacities of up to 200 GB is currently underway.

Supportable File Formats

Blu-Ray discs are capable of supporting different file formats such as MPEG-2, MPEG-4 High Profile AVC and VC-1 coder decoders which enables the discs to store up to four hours worth of HDTV audio-video per layer. It is also capable of supporting the different multi-channel audio file formats such as the different file formats of Dolby and DTS as well as PCM audio file formats. BD rewritable and recordable disc formats will also be backwards-compatible with older formats such as MPEG-2 while newer codecs will enable Blu-Ray technology to support new file formats in the future. The integration of Java cross platform will also enable the Blu-Ray disc to have interactive menus as well as the capability to add new content or updates such as new subtitles through the Internet.

Regional Codes and Security

For security, Blu-Ray supports mandatory HDCP encrypted output, ROM-Mark watermarking, BD+ dynamic cryptology, and the Advanced Access Content System (AACS).

Blu-Ray discs will have three regional codes: one for countries in the Amercian continent as well as countries in east Asia except China and Japan, another for countries in the European and African continents and another one for all the other countries in the Asian continent such as China, Russia, etc.

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LTE

Definition: LTE (Long Term Evolution) is a wireless broadband technology designed to support roaming Internet access via cell phones and handheld devices. Because LTE offers significant improvements over older cellular communication standards, some refer to it as a 4G (fourth generation) technology along with WiMax.

With its architecture centered on Internet Protocol (IP), Long Term Evolution promises to have excellent support for browsing Web sites, VoIP and other IP-based services. LTE can theoretically support downloads at 300 Megabits per second (Mbps) or more based on experimental trials. However, the actual bandwidth available to an individual LTE subscriber will likely be significantly less.

Long Term Evolution technology remains in a research and development mode, and industry specifications are not fully ratified. Expect networking products and services based on LTE to be globally available only in a few more years.

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What is EVDO?

EVDO is an acronym for "Evolution Data Only" or "Evolution Data Optimized" which is a standard for high speed wireless networks used for Broadband Internet connectivity. EVDO enables computer users to have high speed Internet access without the help of a hotspot. Just by inserting an EVDO card into the computer, users get connected to the Internet within seconds and have Net access at DSL-compatible speeds.

While traditional wireless networks assign a dedicated path between the source and destination for the entire duration of the call very similar to fixed-line telephone networks, EVDO transmits several users' data through a single channel using Code Division Multiple Access (CDMA) as well as Time Division Multiple Access (TDMA) to achieve higher throughput and better utilization of network bandwidth.

The standard underwent many revisions denoted as Rev. 0, Rev. A, and Rev. B and so on. Rev. 0 supports forward link speeds up to 2.4 Mbit/s. while Rev. A can go up to 3.1 Mbit/s. EVDO is part of the CDMA2000 family of standards and has been adopted by many service providers offering high speed broadband connectivity for mobile phone users through CDMA networks. It was developed by Qualcomm during the late 90s. Since the standard was a direct evolution from the 1xRTT standard which carried only data, it was initially called Evolution Data only. Later on, since the word 'only' seemed to add a negative connotation to the name, the name was switched to Evolution Data Optimized. Since the new name was more marketable and sounded more hi-tech, it stuck.

EVDO uses the current broadcast frequencies of existing CDMA networks which is a major advantage when compared to competing technologies which often require expensive hardware and software changes or upgrades to the network. Verizon and Sprint are the two major service providers in the US using EVDO. Verizon has implemented Rev. A throughout its network, and Sprint is rapidly catching up. While there is also a large presence of EVDO technology in Korea, it has made relatively no impact in Europe and countries in Asia which predominantly use the W-CDMA standard for high speed data access.

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What is HSDPA?

HSDPA is associated with various Universal Mobile Telecommunications System (UMTS) networks. These include the Global System for Mobile (GSM) Communications.

High-Speed Downlink Packet Access (HSDPA) is also known as High-Speed Downlink Protocol Access. HSDPA is a protocol for mobile telephones. It is a third-generation (3G) High-Speed Packet Access technology designed to speed up network capacity and data transmission rate of cellular phones.

Currently, HSDPA can support speeds ranging from 1.8 Mbps to 14.4 Mbps. While this is not very fast compared to various wired networks, it is a major milestone considering the speed available to cellular technology.

Although HSDPA is mostly identified with its downlink speeds, it also has the ability to greatly expand transfer capacity. HSDPA networks can transfer up to 30 GB of data monthly and as much as 300 minutes of cellular television viewing and 1000 minutes of talk time.

Current HSDPA Technology

At present, there are 100 HSDPA-capable networks operating in 54 countries worldwide. A large number of these networks offer 3.6 Mbps downlink speeds. However, more networks are beginning to switch to faster 7.2 Mbps downlink speeds. Only a number of networks presently offer a full 14.4 Mbps speed

HSDPA competes with a rival format, the Evolution Data Optimized (EVDO) provided by Code Division Multiple Access (CDMA) cellular providers.

HSDPA Capable Devices

Aside from having a cellular plan with a company offering HSDPA access, the only requirement for logging into the HSDPA network is having a cellular device capable of using the technology. A current total of 171 handset models and other mobile devices can use an HSDPA network. Some of these HSDPA capable devices are famous cellular brand and model names such as the Nokia N95, the Palm Treo 750, and the Motorola RAZR as well as many of its various versions.

In addition to the various HSDPA handsets in the market, several HSDPA notebooks and laptops with access to the data network are available. Such products are offered by several major computer manufacturers including Dell, Acer, Hewlett-Packard, Siemens, Fujitsu, Panasonic, and Lenovo.

Future HSDPA Technology

Although 14.4 Mbps is the current cap on downlink speed over HSDPA, networks are preparing to be upgraded with a new type of HSDPA system. Dubbed as HSPA Evolved, this new HSDPA technology is designed to increase download speeds to 42 Mbps upon release, with the possibility of reaching greater speed values in the future.

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What is WCDMA?

WCDMA (Wideband Code Division Multiple Access) is the radio access scheme used for third generation cellular systems that are being rolled out in various parts of the globe. The 3G systems to support wideband services like high-speed Internet access, video and high quality image transmission with the same quality as the fixed networks. In WCDMA systems the CDMA air interface is combined with GSM based networks. The WCDMA standard was evolved through the Third Generation Partnership Project (3GPP) which aims to ensure interoperability between different 3G networks.

The standard that has emerged through this partnership project is based on ETSI's Universal Mobile Telecommunication System (UMTS) and is commonly known as UMTS Terrestrial Radio Access (UTRA). The access scheme for UTRA is Direct Sequence Code Division Multiple Access (DS-CDMA). The information is spread over a band of approximately 5 MHz. This wide bandwidth has given rise to the name Wideband CDMA or WCDMA.

In WCDMA, there are two different modes of operation possible:

* TDD: In this duplex method, uplink and downlink transmissions are carried over the same frequency band by using synchronized time intervals. Thus time slots in a physical channel are divided into transmission and reception part.

* FDD: The uplink and downlink transmissions employ two separated frequency bands for this duplex method. A pair of frequency bands with specified separation is assigned for a connection. Since different regions have different frequency allocation schemes, the capability to operate in either FDD or TDD mode allows for efficient utilization of the available spectrum

Key Features of WCDMA

The key operational features of the WCDMA radio interface are listed below:

1. Support of high data rate transmission: 384 Kbps with wide area coverage, 2 Mbps with local coverage.

2. High service flexibility: support of multiple parallel variable rate services on each connection.

3. Both Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

4. Built in support for future capacity and coverage enhancing technologies like adaptive antennas, advanced receiver structures and transmitter diversity.

5. Support of inter frequency hand over and hand over to other systems, including hand over to GSM.

6. Efficient packet access.

WCDMA Technical Specifications:

Multiple Access Scheme: DS-CDMA

Duplex Scheme: FDD/TDD

Packet Access Dual mode: (Combined and dedicated channel)

Multirate/Variable rate scheme: Variable spreading factor and multi-code

Chip Rate: 3.84 Mcps

Carrier Spacing: 4.4-5.2 MHz (200 kHz carrier raster)

Frame Length: 4.4-5.2 MHz (200 kHz carrier raster)

Inter Base Station synchronization:

FDD: No synchronization needed

TDD: Synchronization required

The chip rate may be extended to two or three times the standard 3.84 Mcps to accommodate data rates higher than 2 Mbps. The 200 kHz carrier raster has been chosen to facilitate coexistence and interoperability with GSM.

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