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1) An oscillation or wave, usually periodic, some characteristic of which is intended to be constrained by modulation to follow the values of a signal or of another oscillation. 2) An electromagnetic wave with stable frequency, suitable for modulation by an information-bearing signal. 3) An unmodulated emission.
1) The nominal frequency of a carrier wave. 2)For certain types of modulation synonym of the centre frequency.
A measure of a central frequency between the upper and lower cut-off frequencies, which determine the bandwidth of the radio channel.
In a given set of radio channels, the difference in frequency between the characteristic frequencies of two adjacent channels.
A frequency which can be easily identified and measured in a given emission.
Type of elliptic polarisation, at which the major and minor axes are equal.
The set of characteristics of an emission, designated by standard symbols, e.g. type of modulation of the main carrier, modulating signal, type of information to be transmitted, and also if appropriate, any additional signal characteristics.
Physically disordered terrain cover structure (around the transmitting and/or receiving antenna).
Transceiver which automatically detects available channels in wireless spectrum and accordingly changes its transmission or reception parameters so more wireless communications (systems) may run concurrently in a given spectrum band at a given place.
A radio system employing technology that allows the system to obtain knowledge of its operational and (eventually) geographical environment, established policies and its internal state; to dynamically and autonomously adjust its operational parameters and protocols according to its obtained knowledge in order to achieve predefined objectives.
1) A statistical measurement of the range of frequencies over which the channel can be considered ""flat"". 2) Measure of the separation in frequency after which two signals (transmitted in the channel) will experience uncorrelated fading.
The time duration over which the channel impulse response is considered to be not varying.
When determining the need for coordination, the area surrounding an earth station sharing the same frequency band with terrestrial stations, or surrounding a transmitting earth station sharing the same bidirectionally allocated frequency band with receiving earth stations, beyond which the level of permissible interference will not be exceeded and coordination is therefore not required.
The line enclosing the coordination area.
When determining the need for coordination, the distance on a given azimuth from an earth station sharing the same frequency band with terrestrial stations, or from a transmitting earth station sharing the same bidirectionally allocated frequency band with receiving earth stations, beyond which the level of permissible interference will not be exceeded and coordination is therefore not required.
Limit distances of coordinated broadcast station from the nearest points placed on the state border, depends on radiated power station, effective antenna height and type of the present radio path, which represent a initial criterion in the coordination process of foreign broadcasting stations.
1) A boundary in a system's frequency response at which energy flowing through the system begins to be reduced (attenuated or reflected) rather than passing through. 2) The frequency either above or below which the power (or power flux density) transmitted (e.g. by radio channel or bandpass filter) has fallen to a given proportion of the power in the passband.