HFC, Wireless, and Mobile Phone Technologies
Hybrid Fiber Optic-Coaxial (HFC)
Hybrid Fiber Optic-Coaxial (HFC) networks combine fiber optics and coaxial cable. This type of network represents the natural evolution of traditional cable television (CATV) networks.
The Headend
The headend is the central body from which the entire system originates. It usually has a set of antennas that receive TV and radio channels from different distribution systems (satellite, microwave, etc.), as well as links to other headends or television studios and other networks to provide information to subscribers through the cable system.
The Backbone Network
The backbone network distributes the composite signal generated by the headend to all distribution areas covered by the cable network. The first step in the evolution of classical CATV coaxial cable networks to HFC telecommunications networks was to replace the long cascades of amplifiers and coaxial cable in the backbone network with point-to-point optical fiber.
Distribution Network
The distribution network consists of a coaxial bus-type structure that conveys signals down to the last pass before the home subscriber. In the case of an HFC, the distribution network normally contains a maximum of two or three broadband amplifiers and includes groups of about 500 homes.
The Drop
The drop is the cable that reaches the homes of subscribers. It is simply the last stretch before docking. In the case of buildings, it is the internal installation.
Overlay
The first technology choice for offering cable telephony is to superimpose a dial-up network onto the network of cable television distribution.
RF and RF to the Kerb/Home
The second option is to build upon the technological infrastructure of the CATV HFC network to carry telephone signals in the RF spectrum of the same.
Unwanted Signals
The coaxial distribution network is a large antenna that can pick up unwanted signals throughout the area it serves.
Via Network Radio
Radio systems present a clear alternative to cable networks for the dissemination of multiple television channels and other multimedia services, and they support interactivity through the return channel.
MMDS Systems
MMDS (Multichannel Multipoint Distribution System) systems emerged in the 1980s as an evolution of MDS (Microwave Distribution System), which formed the first commercial exploitation in the 2 GHz range for direct distribution to subscribers of pay TV channels.
LDMS Systems
LDMS (Local Multipoint Distribution Service) is a technology very similar to MMDS, but with more potential for interactivity with the user, due mainly to its greater bandwidth. The system operates around the 26-28 GHz band, being the only radio link technology that allows high bandwidth in both the television broadcast channel and the return channel.
WiMAX
Standardization: While the project for the creation of a new standard was conceived six years ago in the IEEE, it was not until April 2002 that the first version, 802.16, was released. It referred to fixed radio links with line-of-sight (LOS) between transmitter and receiver, designed to meet the “last mile” (or first, depending on which side you look at), effectively using various frequencies within the 10-66 GHz band.
1G Mobile Telephony
1G (or 1-G) is short for first-generation mobile telephony. These phones used analog technology and were launched in the 1980s. They continued after the commercial launch of second-generation mobile phones. The biggest difference between 1G and 2G is that 1G is analog and 2G is digital. Although both systems use digital systems to connect the radio bases to the rest of the telephone system, the call is encrypted when using 2G.
2G Mobile Telephony
2G mobile is the second generation of mobile telephony. 2G mobile telephony is not a standard or a protocol, but rather a way of marking the change from analog to digital mobile telephony protocols.
3G Mobile Telephony
3G (or 3-G) is short for third-generation mobile telephony. The services associated with the third generation provide the ability to transfer both voice and data (a telephone call) and non-voice data (such as downloading programs, exchanging email, and instant messaging).