Coaxial Cable
Coaxial cable is an electrical cable consisting of a round conducting wire, surrounded by an insulating spacer, surrounded by a cylindrical conducting sheath, usually surrounded by a final insulating layer (jacket). It is used as a high-frequency transmission line to carry a high-frequency or broadband signal. Because the electromagnetic field carrying the signal exists (ideally) only in the space between the inner and outer conductors, it cannot interfere with or suffer interference from ext...
[Posted: 2010-01-14 21:50:09]

What is RF Connectors?
An RF connector is an electrical connector designed to work at radio frequencies in the multi-megahertz range. RF connectors are typically used with coaxial cables and are designed to maintain the shielding that the coaxial design offers. Better models also minimize the change in transmission line impedance at the connection. Mechanically they provide a fastening mechanism (thread, bayonet, braces, push pull) and springs for a low ohmic electric contact while sparing the gold surface thus all...
[Posted: 2010-01-14 21:50:09]

Global Positioning System
The Global Positioning System (GPS) is currently the only fully functional Global Navigation Satellite System (GNSS). Utilizing a constellation of at least 24 medium Earth orbit satellites that transmit precise microwave signals, the system enables a GPS receiver to determine its location, speed and direction. Developed by the United States Department of Defense, it is officially named NAVSTAR GPS (Contrary to popular belief, NAVSTAR is not an acronym for NAVigation Satellite Timing A...
[Posted: 2010-01-14 21:50:09]

Antenna
An antenna is a transducer designed to transmit or receive radio waves which are a class of electromagnetic waves. In other words, antennas convert radio frequency electrical currents into electromagnetic waves and vice versa. Antennas are used in systems such as radio and television broadcasting, point-to-point radio communication, wireless LAN, radar, and space exploration. Antennas usually work in air or outer space, but can also be operated under water or even through soil and rock at cer...
[Posted: 2010-01-14 21:50:09]

GSM
The Global System for Mobile communications (GSM: originally from Groupe Special Mobile) is the most popular standard for mobile phones in the world. GSM service is used by over 2 billion people across more than 212 countries and territories.[1][2] The ubiquity of the GSM standard makes international roaming very common between mobile phone operators, enabling subscribers to use their phones in many parts of the world. GSM differs significantly from its predecessors in that both signaling and...
[Posted: 2010-01-14 21:50:09]

History of GSM
The growth of cellular telephone systems started in the early 1980s, particularly in Europe. The lack of a technological standardization prompted the European Conference of Postal and Telecommunications Administrations (CEPT) to create the Groupe Spécial Mobile (GSM) in 1982 with the objective of developing a standard for a mobile telephone system that could be used across Europe. In 1989, GSM responsibility was transferred to the European Telecommunications Standards Institute (ETSI), and p...
[Posted: 2010-01-14 21:50:09]

Wireless LAN
A wireless LAN or WLAN is a wireless local area network, which is the linking of two or more computers without using wires. WLAN utilizes spread-spectrum or OFDM (802.11a) modulation technology based on radio waves to enable communication between devices in a limited area, also known as the basic service set. This gives users the mobility to move around within a broad coverage area and still be connected to the network. For the home user, wireless has become popular due to ease of ins...
[Posted: 2010-01-14 21:50:09]

SMA connector
SMA (SubMiniature version A) connectors are coaxial RF connectors developed in the 1960's as a minimal connector interface for coaxial cable with a screw type coupling mechanism. The connector has a 50 Ω impedance. It offers excellent electrical performance from DC to 18 GHz. SMA and precision SMA-like connectors are by far the most popular coaxial connector, though by modern standards, their performance and durability are somewhat limited. The SMA connector consists of a 0.250x36 t...
[Posted: 2010-01-14 21:50:09]