Search results
Results from the WOW.Com Content Network
Phase margin and gain margin are two measures of stability for a feedback control system. They indicate how much the gain or the phase of the system can vary before it becomes unstable. Phase margin is the difference (expressed as a positive number) between 180° and the phase shift where the magnitude of the loop transfer function is 0 dB.
The notion of gain and phase margin is based upon the gain expression for a negative feedback amplifier given by = +, where A FB is the gain of the amplifier with feedback (the closed-loop gain), β is the feedback factor, and A OL is the gain without feedback (the open-loop gain). The gain A OL is a complex function of frequency, with both ...
The geometry of these hyperplanes can be treated by using the gain graph with the same vertex set and an edge ij with gain g (in the direction from i to j) for each hyperplane with equation x j = x i + g. These hyperplanes are studied via the lift matroid of the gain graph (Zaslavsky 2003). Suppose the gain group has an action on a set Q.
Randomly varying channel gains such as fading are taken into account by adding some margin depending on the anticipated severity of its effects. The amount of margin required can be reduced by the use of mitigating techniques such as antenna diversity or multiple-input and multiple-output (MIMO). A simple link budget equation looks like this:
A Nichols plot. The Nichols plot is a plot used in signal processing and control design, named after American engineer Nathaniel B. Nichols. [1] [2] [3] It plots the phase response versus the response magnitude of a transfer function for any given frequency, and as such is useful in characterizing a system's frequency response.
In telecommunications, the term fade margin (fading margin) has the following meanings: A design allowance that provides for sufficient system gain or sensitivity to accommodate expected fading , for the purpose of ensuring that the required quality of service is maintained.
Unfortunately this can lead to a poor IP compressor surge margin at part flow. IPC working line, with blow-off valve closed throughout throttle range. Surge margin can be improved by adding variable stators to the IP compressor and/or adding a blow-off valve between the IP and HP compressors. The former makes the IP compressor surge line ...
Figure 5: Bode gain plot to find phase margin; scales are logarithmic, so labeled separations are multiplicative factors. For example, f 0 dB = βA 0 × f 1. Next, the choice of pole ratio τ 1 /τ 2 is related to the phase margin of the feedback amplifier. [9] The procedure outlined in the Bode plot article is followed. Figure 5 is the Bode ...