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Definition
| The first generation of mobile phone service, popular in the 1970's and 1980's, which were routinely analog |
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Definition
| The range of radio frequencies from 2.4 to 2.4835GHz. The 2.4GHz band, which allows for 11 unlicensed channels, is used by WLAN's that follow the popular 802.11b and 802.11g standards, however it is also used for cordless telephone and other transmissions making the 2.4 GHz band more susceptible to interference than the 5GHz. band. |
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Definition
| Second generation mobile phone service popluar in the 1990's. 2G was the first standard to use digital transmission, and as a such, it paved the way for texting and media downloads on mobile web devices. |
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Definition
| Third generation mobile phone service released in the early 2000's, that specifies throughputs of 384 Kbps and packet switching for data (but not voice) communications. |
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Definition
| Fourth generation mobile phone service that is characterized by an all-IP, packet switched network for both data and voice transmission. 4G standards, released in 2008 also specifiy throughputs of 100Mbps for fast moving mobile clients, such as those in cars, and 1Gbps for slow moving mobile clients, such as pedestrians. |
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Term
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Definition
| A range of frequencies four frequency bands: 5.1GHz, 5.3GHz, 5.4GHz, 5.8GHz. It consists of 24 unlicensed bands, each 20MHz wide. the 5GHz band is used by WLANs that follow the 802.11a and 802.11n standards. |
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Term
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Definition
| The IEEE standard for a wireless networking technique that uses multiple frequency bands in the 5GHz frequency range and provides a theoretical maximum throughput of 54 Mbps. 802.11a's high throughput , compared with 802.11b is attributable to its use of higher frequencies, its unique method of encoding data, and more available bandwidth. |
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Definition
| The IEEE standard for a wireless networking technique that uses DSSS (direct-sequence-spread spectrum) signaling in the 2.4-2.4835 GHz frequency range (also called the 2.4GHz band). 802.11b separates the 2.4GHz band into 14 overlapping 22-MHz channels and provides a theoretical maximum of 11Mbps throughput. |
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Definition
| The IEEE standard for a wireless networking technique designed to be compatible with 802.11b while using different encoding techniques that allow it to reach a theoretical maximum capacity 54 Mbps. 802.11g, like 802.11b, uses the 2.4GHz frequency. |
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Definition
| The IEEE standard for a wireless networking technique that may issue signals in the 2.4 or 5Ghz band and can achieve actual data throughput between 65 and 600Mbps. It accomplishes this through several means, including MIMO, channel bonding and frame aggregation. 802.11n is backward compatible with 802.11a, b, and g. |
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Definition
| An IEEE standard for wireless MAN's. 802.16 networks may use frequencies between 2 and 66Ghz. Their antennas may operate in a line of sight or non-line of sight manner and cover 50 kilometers (30 miles). 802.16 connections can achieve a maximum throughput of 70 Mbps, though actual throughput diminishes as the distance between receivers increases. Several 802.16 standards exist. Collectively, they are known as WiMAX. |
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Definition
| Currently, the most widely implemented version of WiMAX. With 802.16e, IEEE improved the mobility and the QoS characteristics of the technology , making it better suited to VOIP and mobile phone users. 802.16e is capable of 70Mbps throughput, but becasue bandwidth is shared and service providers cap data rates, most users actually experience 1-4Mbps throughput. |
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Definition
| Also know as WiMAX 2, the IEEE standard for a version of 802.16 that achieves theoretical throuputs of 330 Mbps with lower latency and better quality for VoIP applications than previous WiMAX versions. 802.16m has been approved as a true 4G Technology. Manufacturers expect it to reach throughputs of 1Gbps in the near future. |
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Term
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Definition
| A device used on wireless LAN's that transmits and receives wireless signals to and from multiple nodes and retransmits them to the rest of the network segment. Access points can connect a group of nodes with a network or two networks with each other. they may use directional or omnidirectional antennas. |
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Definition
| A method used by wireless stations to detect the presence of an access point. In active scanning, the station issues a probe to each channel in its frequency range and waits for the access point to respond. |
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Definition
| A type of wireless LAN in which stations communicate directly with each other (rather than using access point). |
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Term
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Definition
| In the context of wireless networking, the communication that occurrs between a station and an access point to enable the station to connect to the network via that access point. |
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Definition
| AN intermediate connection between subscriber networks and a telecommunications carrier's network. |
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Definition
| In the context of wireless networking, a frame issued by an access point to alert other nodes of its existence. |
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Definition
| In IEEE terminology,a group of stations that share an access point. |
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Term
BSSID
Basic Service Set Identifier |
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Definition
| In IEEE terminology the identifier for a BSS. |
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Definition
| In a cellular network, an area of coverage serviced by an antenna and base station. |
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Term
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Definition
| In the context of 802.11n wireless technology, the combination of two 20MHZ frequency bands to create one 40Mhz frequency band that can carry more than twice the amount of data that a single 20MHZ band could. It's recommended for use only in the 5Ghz range because this band has more available channels and suffers less interference than the 2.4GHz band. |
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Term
CSMA/ca
Carrier Sense Multiple Access with Collision Avoidance |
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Definition
| A network access method used on 802.11 wireless networks. In CSMA/CA, before a node begins to send data it checks the medium. if it detects no transmission activity, it waits a brief, random amount of time, and then its transmission. if the node does not detect activity, it waits a brief period of time before checking the channel again. CSMA/CA does not eliminate, but minimizes, the potential for collisions. |
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Term
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Definition
| In the context of wireless signal propagation, the phenomenon that occurs when an electromagnetic wave encounters an obstruction and splits into secondary waves. the secondary waves continue to propagate in the direction in which they were split. If you could see wireless signals being diffracted, they would appear to be bending around the obstacle. Objects with sharp edges-including the corners of walls and desks-cause diffraction. |
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Term
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Definition
| A type of antenna that issues wireless signals along a single direction or path. |
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Term
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Definition
| In the context of wireless transmission, the connection between a carrier's antenna and a client's transceiver-for example, a smartphone. |
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Term
DSSS
Direct Sequence Spread Spectrum |
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Definition
| A transmission technique in which a signal's bits are distributed over an entire frequency band at once. Each bit is coded so that the receiver can reassemble the original signal upon receiving the bits. |
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Term
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Definition
| A group of access points and associated stations (or basic service sets) connected to the same LAN. |
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Term
ESSID
Extended Service Set Identifier |
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Definition
| A special identifier shared by BSS's that belong to the same ESS. |
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Term
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Definition
| A variation in a wireless signal's strength as a result of some of the electromagnetic energy being scattered, reflected, or diffracted after being issued by the transmitter. |
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Term
FHSS
Frequency Hopping Spread Spectrum |
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Definition
| A wireless signaling technique in which a signal jumps between several different frequencies within a band in a synchronization pattern known to the channel's receiver and transmitter. |
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Term
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Definition
| A type of wireless system in which the locations of the transmitter and receiver are static. In a fixed connection, the transmitting antenna focuses its energy directly toward the receiving antenna. This results in point-to-point link. |
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Term
GEO
Geosynchronous Earth orbit |
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Definition
| The term used to refer to a satellite that maintains a constant distance from a point on the equator at every point in its orbit. Geosynchronous orbit satellites are the type used to provide satellite internet access. |
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Term
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Definition
| The transition that occurs when a cellular when a cellular network client moves from one antenna's coverage area to another. |
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Term
HSPA+
High Speed Packet Access Plus |
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Definition
| A 3G mobile wireless technology released in 2008 that uses MIMO and sophisticated encoding techniques to achieve a maximum 84Mbps downlink throughput and 11Mbps uplink throughput in its current release. Advances in more efficiently using limited channels and incorporating more tennis in MIMO promise to push the maximum downlink data rate to 336 Mbps. |
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Term
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Definition
| A type of WLAN in which stations communicate with an access point and not directly with each other. |
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Term
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Definition
| A command line utility for viewing and setting wireless interface parameters on Linux and UNIX workstations. |
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Term
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Definition
| A wireless signal path or path that travels directly in a straight line from its transmitter to its intended receiver. This type of propagation uses the least amount of energy and results in the reception of the clearest possible signal. |
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Term
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Definition
| A 4G cellular network technology that achieves downlink data rates of up to 1Gbps and uplink rates up to 500 Mbps. ATT&T and Verizon have adopted LTE for their high-speed wireless data networks. |
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Term
MIMO
Multiple In-Multiple Out |
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Definition
| In the context of 802.11n wireless networking, the ability for access points to issue multiple signals to stations, thereby multiplying the signal's strength and increasing their range and data carrying capacity. Because the signals follow multipath propagation, they must be phased adjusted when they reach their destination. |
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Term
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Definition
| A type of wireless system in which the receiver can be located anywhere within the transmitter's range. This allows the receiver to roam from one place to another while continuing to pick up its signal. |
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Term
MSC
Mobile Switching center |
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Definition
| A carrier's facility to which multiple cellular base stations connect. An MSC might be located inside a telephone company's central office or it might stand alone and connect to the central office via fiber optic cabling or a microwave link. Equipment at an MSC manages mobile clients, monitoring their location and usage patterns and switches cellular calls. It also assigns each mobile client IP address. |
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Term
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Definition
| The characteristic of wireless signals that follow a number of different paths to their destination for example, because of reflection, diffraction, and scattering. |
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Term
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Definition
| A type of antenna that issues and receives wireless signals with equal strength and clarity in all directions. This type of antenna is used when many different receivers must be able to pick up the signal , or when the receiver's location is highly mobile. |
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Term
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Definition
| In the context of wireless networking , the process in which a station listens to several channels within a frequency range for a beacon issued by an access point. |
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Term
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Definition
| In 802.11 wireless networking a type of frame issued by a station during active scanning to find nearby access points. |
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Term
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Definition
| The relative strength over a three dimensional area of all the electromagnetic energy an antenna sends or receives. |
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Term
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Definition
| the geographical are in which signals issued from an antenna or wireless system can be consistently and accurately received. |
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Term
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Definition
| In context of wireless networking , the process of a station establishing a connection (or associating) with a different access point. |
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Term
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Definition
| In the context of wireless, the phenomenon that occurs when an electromagnetic wave encounters an obstacle and bounces back toward its source. A wireless signal will bounce off objects whose dimensions are large compared with the signal's average wavelength. |
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Term
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Definition
| In wireless networking, the process that describes a station moving between BSSs without losing connectivity. |
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Term
RTS/CTS
Request to send/clear to send |
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Definition
| AN exchange in which a wireless station requests the exclusive right to communicate with an access point and the access point confirms that it has granted that request. |
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Term
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Definition
| The process a wireless station undergoes to find an access point. |
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Term
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Definition
| The diffusion of a wireless signal that results from hitting an object that has smaller dimensions compared with the signal's wavelength. Scattering is also related tot he roughness of the surface a wireless signal encounters. The rougher the surface, the more likely a signal is to scatter when it hits that surface. |
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Term
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Definition
| In the context of wireless networking, an assessment of client requirements, facility characteristics,and coverage areas to determine an access point arrangement that will ensure reliable wireless connectivity within a given area. |
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Term
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Definition
| A type of wireless transmission in which lower level signals are distributed over several frequencies simultaneously. Spread spectrum transmission is more secure than narrowband. |
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Term
SSID
Service at Identifier |
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Definition
| A unique character string used to identify an access point on an 802.11 network |
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Term
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Definition
| An end node on a network, used most often in the context of wireless networks. |
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Term
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Definition
| The equipment on a satellite that receives an uplinked signal from Earth, amplifies the signal, mnodifies its frequency then retransmits it (in a downlink) to an antenna on Earth. |
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Term
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Definition
| In the context of wireless transmission, the connection between a client's transceiver and a carrier's antenna. |
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Definition
| A type of signal made of electromagnetic energy that ravels through the air. |
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Definition
| An access point that provides routing functions and is used as a gateway. |
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Definition
| An access point that provides routing functions. |
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Term
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Definition
| A continuum of electromagnetic waves used for data and voice communication. the wireless spectrum (as defined by the FCC, which controls its use) spans frequencies between 9KHz and 300 GHz. Each type of wireless service can be associated with one area of the wireless spectrum. |
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Term
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Definition
| A LAN that uses wireless connections for some or all of its transmissions. |
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