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Signal frequency Signals in a waveguide travel at a speed that varies with frequency and the dimensions of the waveguide. In a phased array or slotted waveguide antenna, the signal is designed to reach the outputs in a given phase relationship. This can be accomplished for any single frequency by properly adjusting the length of each waveguide ...
Upfade is a special case of fading, used to describe constructive interference, in situations where a radio signal gains strength. [6] Some multipath conditions cause a signal's amplitude to be increased in this way because signals travelling by different paths arrive at the receiver in phase and become additive to the main signal. Hence, the ...
It does not need to be raining at a location for it to be affected by rain fade, as the signal may pass through precipitation many miles away, especially if the satellite dish has a low look angle. From 5% to 20% of rain fade or satellite signal attenuation may also be caused by rain, snow, or ice on the uplink or downlink antenna reflector ...
Antenna diversity is especially effective at mitigating these multipath situations. This is because multiple antennas offer a receiver several observations of the same signal. Each antenna will experience a different interference environment. Thus, if one antenna is experiencing a deep fade, it is likely that another has a sufficient signal ...
This causes the signal to fluctuate in strength and may cause it to disappear entirely at certain times. The effect can be reduced or eliminated by operating on more than one frequency or using modulation techniques like pulse compression that change the frequency over the period of a pulse.
In telecommunications, the free-space path loss (FSPL) (also known as free-space loss, FSL) is the attenuation of radio energy between the feedpoints of two antennas that results from the combination of the receiving antenna's capture area plus the obstacle-free, line-of-sight (LoS) path through free space (usually air). [1]
The purpose of the antenna is to intercept radio waves from the desired television stations and convert them to tiny radio frequency alternating currents which are applied to the television's tuner, which extracts the television signal. [5] The antenna is connected to the television with a specialized cable designed to carry radio current ...
In practice, the first approximation of coherence time suggests a time duration during which a Rayleigh fading signal may fluctuate wildly, and the second approximation is often too restrictive.