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We are Singapore’s largest content creator and national media network, operating a suite of TV channels, radio stations and multiple digital platforms.
- Who We Are
We are Singapore’s largest content creator and national...
- Who We Are
We are Singapore’s largest content creator and national media network, operating a suite of TV channels, radio stations and multiple digital platforms. We pioneered the development of Singapore’s broadcasting industry with radio broadcast in 1936 and television in 1963.
Oct 27, 2023 · Learn what a media network is, how it works, and why it matters for commerce media. Find out how media networks can help companies monetize data, collaborate with partners, and deliver personalized ads and insights.
Nov 14, 2023 · A retail media network is an asset owned and operated by a retailer which publishes advertisements, or a third-party publisher that contains ads which leverage a retailer’s first-party shopper data.
- Overview
- Transmission media and the problem of signal degradation
- Wire transmission
- Wire media
- Applications of wire
telecommunications media, equipment and systems—metal wire, terrestrial and satellite radio, and optical fibre—employed in the transmission of electromagnetic signals, facilitating mass communication and mass media.
Every telecommunications system involves the transmission of an information-bearing electromagnetic signal through a physical medium that separates the transmitter from the receiver. All transmitted signals are to some extent degraded by the environment through which they propagate. Signal degradation can take many forms, but generally it falls into three types: noise, distortion, and attenuation (reduction in power). Noise is the presence of random, unpredictable, and undesirable electromagnetic emissions that can mask the intended information signal. Distortion is any undesired change in the amplitude or phase of any component of an information signal that causes a change in the overall waveform of the signal. Both noise and distortion are commonly introduced by all transmission media, and they both result in errors in reception. The relative impact of these factors on reliable communication depends on the rate of information transmission, on the desired fidelity upon reception, and on whether communication must occur in “real time”—i.e., as in telephone conversations and video teleconferencing.
Various modulating and encoding schemes have been devised to provide protection against the errors caused by channel distortion and channel noise. These techniques are described in the article telecommunication system. In addition to these signal-processing techniques, protection against reception errors can be provided by boosting the power of the transmitter, thus increasing the signal-to-noise ratio (the ratio of signal power to noise power). However, even powerful signals suffer some degree of attenuation as they pass through the transmission medium. The principal cause of power loss is dissipation, the conversion of part of the electromagnetic energy to another form of energy such as heat. In communications media, channel attenuation is typically expressed in decibels (dB) per unit distance. Attenuation of zero decibels means that the signal is passed without loss; three decibels means that the power of the signal decreases by one-half. The plot of channel attenuation as the signal frequency is varied is known as the attenuation spectrum, while the average attenuation over the entire frequency range of a transmitted signal is defined as the attenuation coefficient.
In wire transmission an information-bearing electromagnetic wave is guided along a wire conductor to a receiver. Propagation of the wave is always accompanied by a flow of electric current through the conductor. Since all practical conductor materials are characterized by some electrical resistance, part of the electric current is always lost by co...
Most modern wire transmission is conducted through the metallic-pair circuit, in which a bundled pair of conductors is used to provide a forward current path and a return current path. The most common conductor is hard-drawn copper wire, which has the benefits of low electrical resistance, high tensile strength, and high resistance to corrosion. The basic types of wire media found in telecommunications are single-wire lines, open-wire pairs, multipair cables, and coaxial cables. They are described below.
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Because of the high signal attenuation inherent in wire, transmission over distances greater than a few kilometres requires the use of regularly spaced repeaters to amplify, restore, and retransmit the signal. Transmission lines also require impedance matching at the transmitter or receiver in order to reduce echo-creating reflections. Impedance matching is accomplished in long-distance telephone cables by attaching a wire coil to each end of the line whose electrical impedance, measured in ohms, is equal to the characteristic impedance of the transmission line. A familiar example of impedance matching is the transformer used on older television sets to match a 75-ohm coaxial cable to antenna terminals made for a 300-ohm twin-lead connection.
Coaxial cable is classified as either flexible or rigid. Standard flexible coaxial cable is manufactured with characteristic impedance ranging from 50 to 92 ohms. The high attenuation of flexible cable restricts its utility to short distances—e.g., spans of less than one kilometre, or approximately a half-mile—unless signal repeaters are used. For high-capacity long-distance transmission, a more efficient wire medium is rigid coaxial cable. The first such transatlantic telephone cable (TAT-1) was laid by a consortium that included the American Telephone & Telegraph Company (AT&T), beginning June 28, 1955, from Clarenville, on the island of Newfoundland in Canada, and reaching Oban, Scotland, on September 25, 1956. TAT-1 had an initial capacity of only 36 two-way voice circuits, but by the time that TAT-6 and TAT-7 were put into service in 1976 and 1978, respectively, capacity had expanded to 4,000 circuits each for those newer cables. However, with the laying in 1987 of the first transatlantic fibre-optic cable (TAT-8), which could carry some 40,000 circuits, the coaxial cables were gradually phased out of service, with TAT-6 and TAT-7 being retired in 1994.
- Alfred O. Hero
The term generally refers to components of the mass media communications industry, such as print media, publishing, news media, photography, cinema, broadcasting (radio and television), digital media, and advertising.
Sep 6, 2022 · In this guide, I’ll discuss the evolution of social media and the top social media networks. I’ll also get into the different brand benefits of each network type.
