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Increasing return loss corresponds to lower SWR. Return loss is a measure of how well devices or lines are matched. A match is good if the return loss is high. A high return loss is desirable and results in a lower insertion loss. From a certain perspective 'Return Loss' is a misnomer. The usual function of a transmission line is to convey ...
There are not always two pantographs on an electric multiple unit but, in cases where there are, the other one can be used if one is damaged; an example of this situation would be a Class 390 Pendolino. The rear pantograph in relation to the direction of travel is often used as to avoid damaging both pantographs in case of entanglements: if the ...
In antenna theory, radiation efficiency is a measure of how well a radio antenna converts the radio-frequency power accepted at its terminals into radiated power. Likewise, in a receiving antenna it describes the proportion of the radio wave's power intercepted by the antenna which is actually delivered as an electrical signal.
An antenna designer must take into account the application for the antenna when determining the gain. High-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully in a particular direction. Low-gain antennas have shorter range, but the orientation of the antenna is inconsequential.
For example, in mixers mismatch loss occurs when there is an impedance mismatch between the RF port and IF port of the mixer [dubious – discuss]. [4] This is one of the principal reasons for losses in mixers. Likewise, a large amount of the loss in amplifiers comes from the mismatch between the
Instead of one antenna with omnidirectional coverage, the station may use as few as 3 (rural areas with few customers) or as many as 32 separate antennas, each covering a portion of the circular coverage. This allows the base station to use a directional antenna that is pointing at the user, which improves the signal-to-noise ratio. If the user ...
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The loss resistance and efficiency of an antenna can be calculated once the field strength is known, by comparing it to the power supplied to the antenna. The loss resistance will generally affect the feedpoint impedance, adding to its resistive component.