Search results
Results From The WOW.Com Content Network
The radio spectrum is the part of the electromagnetic spectrum with frequencies from 3 Hz to 3,000 GHz (3 THz).Electromagnetic waves in this frequency range, called radio waves, are widely used in modern technology, particularly in telecommunication.
Future networks like the LTE standard (defined by 3GPP) are designed for a frequency reuse of one.In such networks, neighboring cells use the same frequency spectrum. Such standards exploit Space Division Multiple Access (SDMA) and can thus be highly efficient in terms of spectrum, but required close coordination between cells to avoid excessive inter-cell interference.
Spectrum management is a growing problem due to the growing number of spectrum uses. [6] Uses include: over-the-air broadcasting, (which started in 1920); government and research uses (which include defense, public safety—maritime, air, police—resource management, transport, and radio astronomy); commercial services to the public (including voice, data, home networking); and industrial ...
Frequency allocation (or spectrum allocation) is the part of spectrum management dealing with the designation and regulation of the electromagnetic spectrum into frequency bands, normally done by governments in most countries. [1]
The radio spectrum is a finite resource, which means there is great need for an effective allocation process. In the United States, the Federal Communications Commission or FCC has the responsibility of allocating discrete portions of the spectrum, or bands, to various industries. The FCC did this recently, when it shifted the location of ...
Notional example of a simple network topology that highlights the current RF spectrum challenges. The network consists of two users, a communications user and a radar user, and a source of external interference. Users can operate either by occupying the same spectrum or by being physically co-located (occupying the same space).
In telecommunications, especially radio communication, spread spectrum are techniques by which a signal (e.g., an electrical, electromagnetic, or acoustic) generated with a particular bandwidth is deliberately spread in the frequency domain over a wider frequency band. Spread-spectrum techniques are used for the establishment of secure ...
Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly changing the carrier frequency among many frequencies occupying a large spectral band. The changes are controlled by a code known to both transmitter and receiver .