| Term |
Description |
| "RF" |
Radio frequency (abbreviated RF,
rf, or r.f.) is a term that refers to alternating current (AC)
having characteristics such that, if the current is input to an
antenna, an electromagnetic (EM) field is generated suitable for
wireless broadcasting and/or communications. [source]
Designation |
Abbreviation |
Frequencies |
Free-space Wavelengths |
Very Low Frequency |
VLF |
9 kHz - 30 kHz |
33 km - 10 km |
Low Frequency |
LF |
30 kHz - 300 kHz |
10 km - 1 km |
Medium Frequency |
MF |
300 kHz - 3 MHz |
1 km - 100 m |
High Frequency |
HF |
3 MHz - 30 MHz |
100 m - 10 m |
Very High Frequency |
VHF |
30 MHz - 300 MHz |
10 m - 1 m |
Ultra High Frequency |
UHF |
300 MHz - 3 GHz |
1 m - 100 mm |
Super High Frequency |
SHF |
3 GHz - 30 GHz |
100 mm - 10 mm |
Extremely High Frequency |
EHF |
30 GHz - 300 GHz |
10 mm - 1 mm |
|
| "3G" |
3G is a short term for third-generation wireless, and refers to near-future developments in personal and business wireless technology, especially mobile communications.
Ultimately, 3G is expected to include capabilities and features such as:
»
Enhanced multimedia (voice, data, video, and remote control)
»
Usability on modes cellular telephone, e-mail, paging, fax,
video-conferencing, and web browsing
»
Broad bandwidth and high speed (upwards of 2 Mbps)
»
Routing flexibility (repeater, satellite, LAN)
»
Operation at approximately 2 GHz transmit and receive frequencies
»
Roaming capability throughout Europe, Japan, and North America
[source]
 top |
Mobile
Internet
Access
WiMAX, etc.
Notes: All speeds are theoretical maximums and
will vary by a number of factors, including the use of external
antennae, distance from the tower and the ground speed (i.e.
communications on a train may be poorer than when standing still.)
Usually the bandwidth is shared between several terminals. |
| Comparison of Mobile Internet Access methods
[ Source - wikipedia ] |
Standard |
Family |
Primary Use |
Radio Tech |
Downlink (Mbps) |
Uplink (Mbps) |
Notes |
| |
WiMAX |
Mobile Internet |
MIMO-SOFDMA |
70 |
70 |
Quoted speeds only achievable at very short
ranges, more practically 10 Mbps at 10 km. |
| |
HIPERMAN |
Mobile Internet |
OFDM |
56.9 |
56.9 |
|
|
WiBro |
Mobile Internet |
OFDMA |
50 |
50 |
Mobile range (900 m) |
| |
iBurst 802.20 |
Mobile Internet |
HC-SDMA |
64 |
64 |
3-12 km |
|
UMTS/3GSM |
Mobile phone |
CDMA/FDD |
.384
14.4 |
.384
5.76 |
HSDPA widely deployed. Typical downlink rates today 1-2Mbps, ~200kbps
uplink; future downlink up to 28.8Mbps. |
| |
UMTS/3GSM |
Mobile Internet |
CDMA/TDD |
16 |
16 |
Reported speeds according to IPWireless using 16QAM modulation similar to HSDPA+HSUPA |
| |
UMTS/4GSM |
General 4G |
OFDMA/MIMO/SC-FDMA (HSOPA) |
>100 |
>50 |
Still in development |
|
CDMA2000 |
Mobile phone |
CDMA |
0.144 |
0.144 |
Obsoleted by EV-DO |
EV-DO 1x Rev. 0
EV-DO 1x Rev.A
EV-DO Rev.B |
CDMA2000 |
Mobile Internet |
CDMA/FDD |
2.45
3.1
4.9xN |
0.15
1.8
1.8xN |
Rev B note: N is the number of 1.25 MHz
chunks of spectrum used. Not yet deployed. |
|
| "802.11" |
802.11 is a family of specifications for
wireless local area networks (WLANs) developed by a working
group of the Institute of Electrical and Electronics Engineers
(IEEE).
802.11b and 802.11g – as well as 802.11n when using
the 2.4 GHz band – divide the 2.4 GHz spectrum into 14 overlapping,
staggered channels whose center frequencies are 5 megahertz (MHz) apart.
The 802.11b, and 802.11g standards do specify the center frequency
of the channel and a spectral mask width to a power level for that channel. The
spectral mask for 802.11b requires that the signal be attenuated by at least 30 dB from its peak energy at ± 11 MHz from the center frequency. This
means that an 802.11b/g product occupies five channels to an energy
level of 30 dB down from the peak or center of the signal.
[ Source - wikipedia ]
top |
| "802.11b" |
802.11b International standard for
wireless networking that operates in the 2.4 GHz frequency range
(2.4 GHz to 2.4835 GHz) and provides a throughput of up to 11 Mbps.
This is a very commonly used frequency. Microwave ovens, cordless
phones, medical and scientific equipment, as well as Bluetooth & Wi-Fi devices, all work within the 2.4 GHz frequency band. [source]
top |
| "802.11g" |
802.11g, offers wireless transmission over relatively short distances at up to
54 megabits per second (Mbps) 802.11g operates in the 2.4 GHz range (2400 MHz) and is compatible with 802.11b Wi-Fi
devices.
top |
| "802.11n" |
802.11n
| Release Date |
Op. Frequency |
Data Rate (Typ) |
Data Rate (Max) |
Range (Indoor) |
| September 2008 |
5 GHz and/or 2.4 GHz |
74 Mbit/s |
248 Mbit/s (2 stream) |
~70 meters |
[ Source - wikipedia ]
top |
"Bluetooth" |
Sources: www.bluetooth.com | www.bluetooth.org
Commemorates a Danish king of the 10th century who unified Denmark and
Norway. Nowadays, Bluetooth unifies communication devices with computing
devices wirelessly.
Bluetooth is a computing and telecommunications industry specification
that describes how mobile phones, computers, and personal digital
assistants (PDAs) can easily interconnect with each other and with home
and business phones and computers using a short-range wireless connection.
Using this technology, users of cellular phones, pagers, and personal
digital assistants such as the PalmPilot will be able to buy a
three-in-one phone that can double as a portable phone at home or in the
office, get quickly synchronized with information in a desktop or notebook
computer, initiate the sending or receiving of a fax, initiate a
print-out, and, in general, have all mobile and fixed computer devices be
totally coordinated.
Bluetooth requires that a low-cost transceiver chip be included in each
device. The tranceiver transmits and receives in a previously unused
frequency band of 2.45 GHz (2450 MHz) that is available globally (with
some variation of bandwidth in different countries). In addition to data,
up to three voice channels are available. Each device has a unique 48-bit
address from the IEEE 802 standard. Connections can be point-to-point or
multipoint. The maximum range is 10 meters. Data can be exchanged at a
rate of 1 megabit per second (up to 2 Mbps in the second generation of the
technology). A frequency hop scheme allows devices to communicate even in
areas with a great deal of electromagnetic interference. Built-in
encryption and verification is provided.
top |
| "HiperLAN" |
HiperLAN is a set of wireless local area network (WLAN) communication standards primarily used in
European countries. There are two specifications: HiperLAN/1 (20Mbps) and HiperLAN/2 (54Mbps). Both have been adopted by the European Telecommunications Standards Institute (ETSI).
Both operate in the 5-GHz range (5000MHz) of the radio frequency (RF)
spectrum
top |
| "Home
RF" |
Source -
Link: HomeRF
Designed specifically for wireless networks in homes - in contrast
to 802.11, which was created for use in businesses -- HomeRF
networks are designed to be more affordable to home users than other
wireless technologies. Based on frequency hopping and using radio
frequency waves for the transmission of voice and data, HomeRF has a
range of up to 150 feet.
top |
| "LMDS" |
The term LMDS stands for Local Multipoint Distribution Service
top |
| "Telematics" |
Telematics is the term used to describe a wide variety of wireless
in-car services ranging from navigation aids and remote engine
diagnostics to various forms of wireless communications.
Links: more
info | more info
top |
| "UWB" |
Ultra-wideband (UWB)
+ 100M bps
+ 30 foot range
+ Aimed at transferring video within the home
top |
| "Wi-Fi" |
 Wi-Fi Glossary [source: link]
802.11b Wireless Ethernet is the most popular wireless Internet access
technology. Also known as Wi-Fi, this technology creates a Local
Area Network (LAN) - just like the one at your place of work. Radio
frequency (RF) connections between a base station and laptop computers
fitted with add-on wireless cards replace the wires and cables of a
conventional Local Area Network.
Wireless Ethernet LANs deliver high-bandwidth access -- performance for
various protocols varies from 2Mb per second to 11Mb per second.
Wireless Ethernet LANs have a coverage area of between 200 to 600 feet
per radio transceiver - perfect for airport lounges, hotels and public
meeting places.
top |
| "WLAN" |
A wireless LAN = WLAN is one in which a mobile user can connect to a local area network
(LAN) through a wireless (radio frequency) connection. A standard, IEEE 802.11, specifies the technologies for wireless LANs.
Source -
Links: more
info | more info
top |
All trademarks and /or copyrighted information included above, is the
property of the respective author.
Copyright and all rights therein
are retained by authors or by other copyright holders
|
