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| 0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z |
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| | | 0 | | 1x(CDMA2000) | CDMA2000 is a third-generation (3G) wireless technology that is evolved from existing CDMA 2G technology. Its main features are faster data rates, always-on data service, and improved voice network capacity (more people can use each tower at the same time). Cdma2000 will be deployed in at least three phases.
The first, 1xRTT, supports up to 144 Kbps packet data speeds. It also doubles voice capacity over previous CDMA networks (IS-95).
The second release of 1x, 1xEV-DO, will support data rates up to 2.4 Mbps. It can only be deployed separately from voice networks - in its own spectrum - although devices can be made to access both networks.
The third, 1xEV-DV, supports circuit and packet data rates up to 3-5 Mbps. It fully integrates with 1xRTT voice networks. A possible fourth phase is cdma2000 3x, although it uses three times as much spectrum. | | | 1xEV-DO | Part of a family of cdma2000 1x digital wireless standards. 1xEV-DO is a "3G" standard. EV-DO stands for "EVolution, Data-Optimized"
1xEV-DO is based on a technology initially known as "HDR" (High Data Rate) or "HRPD" (High Rate Packet Data), developed by Qualcomm. The international standard is known as IS-856.
Unlike other "1x" standards, EV-DO only addresses data - not voice. It requires a dedicated slice of spectrum, separate from voice networks using standards such as 1xRTT.
1xEV-DO offers very high data rates - up to 2.4 mbps - averaging 300-600 kbps in the real world. This is much faster than the 50-80 kbps typically offered by 1xRTT technology. | | | 1xEV-DV | (EVolution, Data and Voice) It addresses both data and voice, unlike 1xEV-DO, which only addresses data.
1xEV-DV combines the high-speed HDR technology from 1xEV-DO with the widely-deployed 1xRTT standard. It integrates seamlessly with 1xRTT, providing full backward-compatibility and simultaneous voice and data.
There are two versions of 1xEV-DV currently being prepared: "Release C" and "Release D".
Release C provides high speeds only for the forward link, meaning only "download" speeds are fast. The reverse link ("upload") is the exact same as the slower 1xRTT standard.
Release D provides fast data speeds in both directions, making it ideal for applications such as video conferencing and uploading large files (such as photos from mega pixel camera phones). | | | 1xRTT | (single carrier, radio transmission technology) The first in a family of cdma2000 1x digital wireless standards designed to extend and replace the IS-95 CDMA standard. 1xRTT is sometimes referred to as a "2.5G" or "3G" standard.
Compared to the IS-95 CDMA technology it replaces, 1xRTT offers increased network voice capacity. This benefit requires support on both the base station (tower) and handset (phone). If everyone using a given tower has a 1xRTT phone, twice as many people can use that tower at the same time, compared to the old IS-95 standard.
1xRTT also offers much faster data speeds. The initial release - release 0 (zero) - supports data speeds peaking at 144 kbps. Typical real-world speeds are closer to 60-80 kbps.
A second release of 1xRTT is planned - release A. Release A doubles data rates at 288 kbps peak. | | | 3G | Stands for 3rd-generation. Analog cellular phones were the first generation. Digital marked the second generation.
3G is loosely defined, but generally includes high data speeds, always-on data access, and greater voice capacity.
The high data speeds are possibly the most prominent feature, and certainly the most hyped. They enable such advanced features as live, streaming video.
There are several different 3G technology standards. The most prevalent is UMTS, which is based on WCDMA. (WCDMA and UMTS are often used interchangeably.) UMTS is the 3G technology of choice for most GSM carriers.
The other major standard is cdma2000, which is an evolution of CDMA 2G technology. There are several types of cdma2000, each offering different data rates and levels of compatibility with 2G CDMA. | | | 802.11 | 802.11 is a set of technical specifications for networking and wireless communication, standardized by IEEE.
There are several variants of 802.11. The most common is 802.11b, also known as Wi-Fi, which provides speeds up to 11 mbs. 802.11g and 802.a are faster versions. Many 802.11g and 802.11a products are backward-compatible with the original 802.11b. | | | |
| A | | AMR | (Adaptive Multi Rate) AMR is an advanced voice codec for GSM. A voice codec translates sound (voice) into digital data and vice-versa. AMR is more efficient than older codec's such as FR, EFR, and HR. Increased efficiency provides increased network capacity as more phones with AMR are deployed. Increased network capacity means more people can use each tower at the same time, reducing failed/dropped calls.
AMR gains efficiency by being "adaptive". Unlike older standards, AMR automatically operates in different modes depending on signal conditions, and continuously adjusts to match the sounds being transmitted. | | | Airplane Mode | Some phones and other wireless devices have a special "airplane mode" that turns off just the wireless radio parts of the device, for safe use on an airplane.
Most airlines and many governments ban the use of wireless radio devices during flight, to prevent interference with the plane's radio and navigation systems.
Airplane mode therefore allows the user to safely use the non-wireless functions of a phone (such as games or organizer functions) on an airplane during flight. However, not all airlines have policies that accommodate devices with airplane mode; some airlines still ban the use of all phones during flight regardless. | | | Alphanumeric | | A message or other type of readout containing both letters ("alphas") and numbers ("numerics"). In cellular, "alphanumeric memory dial" is a special type of dial-form-memory option that displays both the name of the individual and that individual's phone number on the cellular phone handset. The name also can be recalled by using the letters on the phone keypad. By contrast, standard memory dial recalls numbers from number only locations. | | | AMPS | | (Advanced Mobile Phone Service) The standard technology in North America for analog phones, first developed and implemented in 1983. See Analog for more information. | | | Analog | | A method of modulating radio signals so they can carry information. A transmission method employing a continuous (rather than pulsed or digital) electrical signal that varies in amplitude or frequency in response to changes in sound impressed on a transducer in the sending device. In contrast to digital technology, which allows upwards of 15 calls per channel, analog only permits 1 call per channel. | | | APC | | (Adaptive Power Control) Found on certain models, it reduces the phone's overall power consumption and increases the battery's charge life. | | | Asynchronous | | A way to send information at non-regular intervals. Information is sent as necessary, instead of synchronized with a time signal, as with Synchronous communication. | | | Attenuation | | The decrease in signal strength as a result of absorption and scattering of energy by objects such as buildings, trees, people, etc. Does not include the reduction due to distance. | | | |
| B | | Band | | Frequencies which are within two defined limits of the radio frequency spectrum, and which are used for a specific purpose. For instance, in the business spectrum we refer to radios that operate in Low Band, High Band, UHF, VHF, 800 and 900 MHz "Bands" of frequencies. | | | Bandwidth | The width or capacity of a communications channel. Analog bandwidth is measured in Hertz (Hz) or cycles per second. The actual bandwidth size is the difference between the lowest and highest frequency in the band, which determines how much information can be transmitted at once. Digital bandwidth is the amount or volume of data that may be sent through a channel, measured in bits per second, without distortion.
Bandwidth should not be confused with the term band, such as a wireless phone that operates on the 800 MHz band. Bandwidth is the space it occupies on that band. The relative importance of bandwidth in wireless communications is that the size, or bandwidth, of a channel will impact transmission speed. Lots of data flowing through a narrow channel takes longer than the same amount of data flowing through a broader channel. | | | Baud | | One change in the amplitude, phase or frequency of a signal, used to encode the signal with digital information. | | | Binary | | A number system that is base-two, meaning each position must be either "0" or "1". Used for all digital communications. | | | Bit | | The smallest unit of information. A bit is a binary unit, represented by either a "0" or a "1". The word "bit" is a contraction of "binary digit". | | | Bluetooth | Bluetooth is a short-range wireless technology used to create PANs (Personal Area Networks) among your devices and with other nearby devices.
Bluetooth allows you to leave your phone in your pocket, while talking on your phone with a Bluetooth headset - with no wires. You can also exchange contact or scheduling information with other Bluetooth-enabled phones nearby, or send such information to a nearby Bluetooth-enabled printer.
Another common use is to give your laptop computer or PDA wireless high-speed Internet access via Bluetooth and your phone. Bluetooth is named for the 10th century Viking, King Herald Bluetooth. | | | bps | (Bits per second) A measurement of data transmission speed. Measures the numbers of bits (a bit is either a "1" or a "0") transmitted in a second. Loosely following the metric system, bps can also be express in kbps (1,000 bits per second) or Mbps (1,000,000 bits per second).
In wireless systems, this is often either a "peak" or "average" number. Peak is a theoretical maximum - rarely achieved outside of a lab. Average is generally a more realistic number. | | | BREW | | (Binary Runtime Environment for Wireless), is a solution developed by Qualcomm for downloading small applications and content to mobile phones. Found almost exclusively in CDMA phones, (currently Verizon only). The primary component lets users download and run small software applications on wireless devices, including phones. Such applications might include games, expense tracking software, or interactive map tools. This component of BREW competes with (J2ME) (Java 2 micro edition), a Java technology from Sun Microsystems. BREW and Java are generally not compatible. | | | Broadband | 1. A term used to compare frequency bandwidth greater than 3 MHz narrowband frequencies. Broadband frequencies can transmit more data and at a higher speed than narrowband frequencies. In general, typical paging services utilize narrowband frequencies. Wireless phones and communication devices use broadband.
2. High-speed data transmission. Often associated with high-speed Internet access. Generally fast enough to support applications such as streaming video. | | | Byte | | A sequence of adjacent bits (usually 8) considered as a unit. A bit is a binary unit - a "1" or a "0". | | | |
| C | | Call Forwarding | | Forwards calls automatically to a number of your choice; some carriers charge airtime during the forwarded call. Some people find convenience and savings in having calls forwarded to them at their desk telephone during work hours. | | | Call Restriction | | Enables a wireless phone to prevent certain types of calls from being made, i.e. permitting only local calls, or allowing only incoming but not outgoing calls. | | | Carrier | | A company that owns a frequency and infrastructure equipment in a specific geographical area. | | | CCD | (charge-coupled device), is a type of image sensor. In effect, it is the "eye" of a camera phone, digital camera, or video camera. It is a device similar to a computer chip, which senses light focused on its surface, like electronic film. CCD is one of two main types of image sensor. The other type is CMOS.
CCD sensors require some additional circuitry compared to CMOS sensors, which can have a minor negative impact on size, cost, and battery life in small devices such as camera phones. | | | CDPD | (Cellular Digital Packet Data) An open wireless transmission standard allowing two-way 19.2-Kbps packet data transmission over existing cellular telephone channels (AMPS with CDPD capability.) In essence, CDPD technology uses idle network capacity caused by pauses in phone conversations and gaps between calls placed, etc. to transmit data. Because it is packet-based, it does not require a continuous circuit (connection), like a voice call.
CDPD is an older technology that has mostly been replaced by newer GPRS and CDMA 1xRTT networks. | | | Cell Cite | | Where a wireless antenna and network communications equipment is located. | | | CIF | | (Common Intermediate Format) A standard size for images produced by low-resolution digital cameras and video cameras. CIF images are 352 pixels wide and 288 pixels tall (352 x 288). CIF is larger than QCIF, but smaller than VGA. | | | Clone | | Refers to a wireless phone programmed with stolen data from a legitimate phone, allowing calls to be made under someone else's account. Theoretically, only analog phones can be cloned. | | | CMOS | | (complementary metal oxide semiconductor), is a type of image sensor. In effect, it is the "eye" of a camera phone, digital camera, or video camera. It is a device similar to a computer chip, which senses light focused on its surface, like electronic film. CMOS is one of two main types of image sensor. The other type is CCD. In the past, CCD image sensors provided better image quality, but the newest and best CMOS sensors match CCD quality. CMOS sensors have basic image-processing circuitry integrated that CCD sensors do not. This gives devices with CMOS sensors a slight edge in the areas of size, cost, and battery life. | | | CMRS | | (Commercial Mobile Radio Service) FCC-designated term for any carrier operating for profit or whose wireless network is connected to the public switched telephone network. | | | Codec | | Acronym for coder-decoder. An electronic device, circuit, or software that converts analog signals, such as video and/or voice signals, into digital form, and vice-versa. Usually also includes digital compression technology for added efficiency. Different codecs may provide different efficiency, quality, and features. | | | Concatenated SMS | | (Long SMS) A feature allowing sending and receiving text messages (SMS) (Short Message Service) longer than the usual 128 or 160 character limit. Long messages can be composed as one, and are automatically split up into smaller messages to send over the network. Maximum lengths vary, from about 300 character to over 1,000, depending on the phone. | | | Contention | | A condition that arises when two or more data stations attempt to transmit at the same time over a shared channel. | | | CPP | | (Calling Party Pays) More common outside the U.S., a service offered by some calling plans in which the caller is billed and not the receiver; the user pays for calls received as well as for calls placed. | | | Crosstalk | | Any phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel. Typically rare in modern digital wireless phone systems, but known to occur mainly in the past on Analog Networks. | | | CTIA | | (Cellular Telecommunications Industry Association) An association, located in Washington, D.C., that represents the interests of the wireless telecommunications industry. | | | |
| D | | Digital | | The use of Binary data to represent information. In digital wireless phone systems, voice sounds are converted (encoded) to a binary stream of data that "describes" the sound. On the other end, the digital signal is decoded and used to reconstruct the sound. This is contrast to analog wireless phone systems, which convert the sound directly into variations in the radio signal. | | | Digital Zoom | Zoom is a feature of many cameras and camera phones that make the subject appear "closer", filling more of the image area. There are two types of Zoom; Optical and Digital.
Digital zoom is a software feature that uses one of two methods: One type of digital zoom simply "crops" the edges of the image. There is no loss in quality, but the resulting image is smaller than the maximum resolution of the camera. The image has the same exact amount of detail as a non-zoomed at full size. The other type uses software to stretch the cropped image larger. The resulting image is the same size as the maximum resolution, but because it has been stretched, no additional detail is visible, meaning the image appears much blurrier than a non-zoomed photo.
Optical zoom uses moving lenses for maximum quality. Unlike digital zoom, optical zoom has no trade-offs in quality or image size. | | | DRM | | (Digital Rights Management) Technology designed to manage, control, or track the distribution and/or use of copyright-protected data. In phones, DRM is used to prevent or control actions such as sending downloaded ring tones, graphics, and video to other people. | | | Dual-Band | A designation indicating that a phone supports two different frequency bands. Not meaningful without knowing which two bands and which technologies the phone will work with.
For North American TDMA and CDMA phones, dual-band indicates that the phone will work in both the 800/850 MHz band and the 1900 MHz band. Most current TDMA phones in the U.S. are tri-mode, meaning they can use both analog and digital in the 800/850 band. Dual-band CDMA phones can be dual-mode or tri-mode. Dual-mode phones only support analog or digital on the 800/850 band, while tri-mode phones support both. The 1900 MHz band is always digital.
A dual-band GSM phone supports two of the four major GSM bands. Depending on which bands, the phone may only work in certain parts of the world. A GSM 850/1900 phone will only work in the Americas. A GSM 900/1800 phone will only work in Europe, Africa, Asia, and Brazil. A GSM 900/1900 phone will work on at least one network in most countries around the world. | | | Dual-Mode | 1. A phone that supports both analog (AMPS) and a digital technology, such as CDMA or TDMA. The digital mode could operate in either the 800/850 MHz frequency band or the 1900 band.
2. A phone that supports both 2G and 3G technologies, such as a GSM/UMTS phone.
Duplex: Full-Duplex refers to simultaneous two-way transmission, such as experienced in a phone conversation. Both ends of the connection can hear each other at the same time.
Half-Duplex, in contrast, will transmit in only one direction - from the loudest noise - at a time. When one person is speaking, the other cannot be heard. | | | |
| E | | E911 | | A wireless 911 service being developed that will automatically provide the caller's identification and geographic location to the 911 call center, facilitating police and rescue service dispatch to the scene. Sometimes referred to as location. | | | ECML / Digital Wallet | | ECML stands for Electronic Commerce Modeling Language. ECML is an open Internet standard for digital wallets and online merchants to facilitate automatic exchange of transaction information. It allows fast and secure online payment via a "digital wallet" in the phone. | | | EDGE | | (Enhanced Data for Global Evolution) An upgrade for GSM/GPRS networks that triples data speeds over standard GPRS. Because it is based on existing GSM technology, EDGE is a smooth upgrade for GSM network operators. It also works within existing spectrum, making it ideal for countries without dedicated 3G spectrum, such as the US. | | | EL | | (Electro-Luminescent) EL refers to a type of light-emitting device that can cover a large area. When electricity is applied, an EL panel glows over its entire surface. EL panels are often used in mobile phones as backlights for LCD displays. EL backlights are characterized by smooth, even light across the display, and often greater brightness than LED backlights. Most EL backlights are blue or aqua in color. | | | EMS | | (Enhanced Messaging Service), is a direct descendent of SMS (Short Messaging Service). EMS extends text messaging to include pictures, melodies, animations and long, formatted text messages. EMS is frequently used to send ring tones and wallpapers to phones from the web. | | | ESN | | (Electronic Serial Number) An electronic identification number of a phone. Similar in function to a car's VIN (vehicle identification number). This number is used by manufacturers and carriers to give each and every phone a unique identification. | | | |
| F | | Fast Busy | | tone heard on a cellular phone when the nearest cell site has reached its capacity of active calls or also if there is no signal detected by a phone and the "Send" key is pressed before logging on the system. | | | FCC | (Fedederal Communications Commission) The Federal Communications Commission (FCC) is an independent United States government agency, directly responsible to Congress. The FCC is charged with regulating interstate and international communications by radio, television, wire, satellite and cable. The FCC's jurisdiction covers the 50 states, the District of Columbia, and U.S. possessions.
The FCC's Office of Engineering and Technology (OET) certifies all mobile phones intended for use in the US, insuring compliance with spectrum allocations, technical standards, and safe SAR (radiation) levels.
The FCC also manages the spectrum allocated to the various mobile phone carriers, via a system of licenses. Each license covers a specific range (band) of frequencies, and a specific geographic area. | | | FDMA | | Frequency Division Multiple Access. An older analog technology used by some wireless carriers. | | | FER | | (Frame Error Rate) Ratio of data transmitted with errors, to total data transmitted. Used to determine the quality of a signal. If the FER is too high, (too many errors,) the connection may be dropped. | | | Firmware | Phones need to store various non-permanent things, too, such as an operating system, roaming instructions, and your phone book. Firmware uses special memory chips that can hold information even when the phone is turned off and battery-less. It's sort of like hardware, because it acts just like a permanently-wired chip, but it's also like software because it can be changed at any time.
So firmware is technically how your phone stores its phone book, but when most people here talk about firmware, they are talking about the roaming instructions (PRL) or operating system. | | | Flex | A new paging protocol that eliminates the need for a Flex pager to constantly remain on scanning constantly, thus extending battery life for up to 5 hours. Also increased message reliability and faster throughput at flexible baud rates of up to 9600 BPS. These are other additional characteristics of Flex paging.
Forward Link: The wireless connection over which information is sent from a cellular base station (tower) to a mobile phone; the opposite of a reverse link. The forward link is analogous to downloading as opposed to uploading. | | | Footprint | | The geographic area in which service is provided for a particular market. | | | Frequency | | The number of complete cycles per second of alternating current or radio waves, usually measured in Hertz (Hz) - cycles per second. Also the way to note a general location on the radio frequency spectrum such as 800 MHz, 900 MHz or 1900 MHz. A frequency is used to transfer information by voice or data in a mobile communications system. | | | Fringe Area | | The area or locality at such a distance from the transmitter that the signal received is weak. Usually referring to the outlying area of a carrier's service coverage. | | | |
| G | | GHz | | (Gigahertz) A unit of frequency equal to one billion cycles per second (Hertz). Wireless mobile phone communications in the United States occur in the 0.8 GHz and 1.9 GHz bands (better known as 800 and 1900 MHz, respectively). 1 GHz = 1,000 MHz = 1,000,000 KHz | | | GPRS | | (General Packet Radio Service) A packet-switched technology that enables high-speed wireless Internet and other data communications. GPRS offers a tenfold increase in data speed over previous technologies, up to 115kbit/s (in theory). Typical real-world speeds are around 30-40 Kbps. Using a packet switching, subscribers are always connected and always on-line, so services will be easy and quick to access. GPRS is considered a "2.5G" technology, meaning it is more advanced than standard 2G digital technology, but does not meet the requirements of a full-feldged 3G technology. | | | GPS | | (Global Positioning System), is a global satellite-based system for determining precise physical location. Most phones with "GPS" in fact use A-GPS technology. The "A" stands for assisted, and means that the phone relies the network for help in determining location. Although the phone does receive GPS signals directly from the satellites, it can't determine actual location without help from the cell network. | | | gpsOne | | gpsOne is a position location technology developed by SnapTrack, a subsidiary of Qualcomm. GpsOne is an A-GPS technology, meaning it uses GPS satellites in conjunction with land-based stations (towers) to determine a phone's location. Phones with gpsOne can receive raw signals directly from GPS satellites, but require a live connection to a network-based location server to do so. The location server helps the phone find the correct satellites. The location server also processes the raw signals and makes the final calculations that determine location. gpsOne is integrated into most Qualcomm CDMA chipsets, and is the position location technology used by most CDMA carriers. | | | GSM | | (Global System for Mobile Communication) GSM is currently the dominant 2G digital mobile phone standard for most of the world. It determines the way in which mobile phones communicate with the land-based network of towers. GSM has not been the most popular standard in the United States in the past. CDMA and TDMA, competing standards, together shared most of the market. However, AT&T Wireless and Cingular, who both used TDMA technology, recently switched to GSM technology. This will narrow the major technologies in the US to two - GSM and CDMA. The most visible feature of GSM are SIM cards. SIM cards are removable, thumbnail-sized smart cards which identify the user on the network, and can also store information such as phone book entries. SIM cards allow users to switch phones by simply moving their SIM card from one phone to the other. | | | |
| H | | Handoff | | In wireless mobile phone systems, the process of transferring a phone call in progress from one base station (tower) and frequency pair to another base station using a different frequency pair, without interruption of the call. Many phones and networks are also capable of performing handoffs between different technologies. For example, a digital (CDMA or TDMA) call might be handed off to an analog (AMPS) tower in the middle of the call, if the digital signal became too weak. | | | Haptics | A category of technology that allows users to "touch" or "feel" virtual things via mechanical simulation. In phones, haptics are typically implemented as advanced vibration mechanisms that provide physical feedback coordinated with the interface, applications, and/or games.
For example, a phone with haptics might allow a user to "feel" a click each time they scrolled through a menu item, or "feel" the rough edge of the road in a racing game. | | | Host Carrier | | The carrier that acts as a temporary cellular provider for a roaming caller. | | | HRPD | | Commonly known as 1xEV-DO. HRPD stands for "high rate packet data". It is a high-speed CDMA-based wireless data technology developed by Qualcomm. It was also known as "HDR" (high data rate) at one point. IS-856 is the official international standard designation. | | | HSDPA | | (High Speed Downlink Packet Access) is an upgrade for WCDMA networks. It doubles network capacity and increases download data speeds five-fold. | | | Hz | | (Hertz) The unit of frequency measurement equal to one cycle per second. Abbreviated Hz and named after Heinrich R. Hertz. | | | |
| I | | iDEN | | iDEN is a TDMA-based digital wireless standard designed to work in special frequencies originally designated for analog Specialized Mobile Radio (SMR) networks. iDEN was invented by Motorola, who remains the primary manufacturer of iDEN devices. iDEN provides several unique features, including integrated push-to-talk (PTT) walkie-talkie capability. IDEN is used in the U.S. by Nextel and Southern LINC. | | | IMEI | | International Mobile Equipment Identifier. A 15-digit number (composed of four parts) that uniquely identifies an individual wireless device. The IMEI is automatically transmitted by the phone when the network asks for it. A network operator might request the IMEI to determine if a device is in disrepair, stolen or to gather statistics on fraud or faults. | | | IMSI | | (International Mobile Subscriber Identity) The identifier, under GSM specifications, which uniquely identifies each phone on the system. | | | Infrared | | (IR), can be used to connect the phone to various devices, for various purposes. Infrared is a line-sight wireless technology that uses a beam of invisible light to transmit information. The infrared ports of both devices must be nearby and aimed at each other for a connection to work. It can connect the phone to a computer, so that the computer can use the phone to make a data connection (to the Internet, for example.) It can also be used to exchange information such as phone book entries with other phones. Finally, some phones can also use it to send information such as phone book entries and calendar events to Infrared-equipped printers. | | | IP | | (Internet Protocol) A standard protocol designed for use in interconnected systems of packet-switched computer communication networks. The basis of the Internet, and the standard that will eventually be used for most wireless 3G network infrastructure. | | | ITU | | (International Telecommunication Union) A civil international organization established to promote standardized telecommunications on a worldwide basis. The ITU headquarters is located in Geneva, Switzerland. | | | |
| J | | J2ME | (Java 2 Micro Edition), is a feature that allows the device to run specially-written applications.
J2ME applications can provide specific functions such as a tip calculator, they can be games, or they can be custom-written corporate applications. They can be Internet-enabled, so that, for example, a J2ME game might let you play someone else in real time over the Internet. They can be created by anyone - not just the phone manufacturer or your carrier. You can download new applications to your phone at any time. Most phones allow you to download new applications directly to your phone using the Wireless Internet feature. | | | |
| K | | Keitai | | A Japanese term referring to cell phones and related products and services. Associated with the extreme popularity of cell phones in Japan, and the unique cultural trends associated with them. | | | Kilohertz (KHz) | | A measurement of the frequency of a signal equivalent to one thousand cycles per second. | | | |
| L | | Landline | | Non-cellular provider of telephone service for a particular location. Hardwired Plain Old Telephone (POT). | | | LCD | | (Liquid Crystal Display) The predominant display technology used in mobile phones. LCD displays have low energy requirements and are generally easy to read. LCDs in mobile phones generally work by transmitting or blocking light across a grid of extremely tiny square areas called "pixels". Monochrome (black & white) LCDs in phones also usually have both a backlight and a reflective backing, allowing them to be equally usable in both bright light and complete darkness. Many newer LCD displays are "transflective", meaning they combine the best properties of both transmissive and reflective displays. Transflective LCD displays have backlights that provide good brightness and color in dim and medium light, while also working well in bright light such as outdoors. | | | LED | | (Light-Emitting Diode) A small semiconductor device that emits light when charged with electricity. LEDs come in many colors, and some LEDs contain multiple elements and are therefore capable of multiple colors. LEDs are often used for LCD display backlights. LEDs are also used for keyback backlights, and service/message lights. | | | LEO | | (Low Earth Orbit Satellite) Satellites with orbiting altitudes typically about 400 to 1200 miles above Earth, which is much lower than geostationary orbiting altitude of around 23,000 miles. LEO satellite orbits keep the audio delay low. These satellite-based systems can be found in Motorola's Iridium system and in Qualcomm's Globalstar system. | | | Lithium Ion | | An ultra lightweight material used in new batteries that can hold 1.5 times more energy than a Nickel Metal Hydride battery and can last over 1000 full charge cycles. This type of battery is found in today's most high-end phones due to its enormous versatility. | | | Lithium Polymer | | A battery technology similar to Lithium-ion. Current "lithium-polymer" batteries are technically "lithium ion polymer", since pure lithium-polymer batteries are not yet commercially viable. Pure lithium-polymer batteries, once available, will theoretically provide considerable benefits over current battery technologies. Today's lithium-ion polymer batteries perform similarly to lithium-ion batteries, but can be made much thinner - as thin as 1mm. | | | |
| M | | Megahertz (MHz) | | One million frequency oscillations per second | | | Megapixel | | This term refers to the size of an image, usually in reference to a photo from a digital camera or camera phone. Megapixel means one million pixels. The resolution of digital cameras and camera phones is often measured in megapixels. Since pixels are usually square and form a grid, a one-megapixel camera will produce an image roughly 1200 x 900 pixels. Megapixel images are much larger than a phone display, so a megapixel camera will not make much difference compared to a sub-megapixel camera for phone-only applications such as MMS. Rather, megapixel cameras are useful for taking photos suitable for viewing on a PC and/or printing. | | | Memory Effect | | The deterioration of battery life in a Nickel Cadmium cell caused by charging the battery before being completely discharged. | | | Microwave | | The portion of the frequency spectrum above 1000 MHz. This type of device is used to transmit radio frequency extensively for long-distance telephone transmission. Digitally encoded messages are sent through microwave channels either between terrestrial antennae, via satellite, or through wave-guides. | | | MIDI | | (Musical Instrument Digital Interface), is a set of specifications for describing music. Instead of capturing and storing the sound of music, MIDI information describes the instruments, notes, and timing of the music, which can then be recreated on MIDI-capable devices. A simple MIDI device might only reproduce the notes, while more sophisticated devices can create realistic-sounding music by synthesizing individual instruments. If multiple instruments can be recreated simultaneously, this is called polyphony (Polyphonic Ringtones). Standard MIDI files can be transferred to a MIDI-capable phone and used as a ringtone. | | | MIN | | (Mobile Identification Number) A unique 24-bit number assigned by the wireless service provider (carrier) to each phone it sells or includes in service plans. Unlike an Electronic Serial Number (ESN), a MIN is changeable because wireless phones may change hands or phone owners may move to another coverage region, requiring a different service plan. The MIN and ESN are both automatically transmitted to the wireless network each time the phone is used to verify that the phone has not been reported lost or stolen and that all subscriber bills are current | | | MMS | | (Multimedia Messaging Service), is a descendent of SMS (Short Messaging Service). MMS extends text messaging to include longer text, graphics, photographic imagery and audio |
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