modulation index

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modulation index

[‚mäj·ə′lā·shən ‚in‚deks]
(communications)
The ratio of the frequency deviation to the frequency of the modulating wave in a frequency-modulation system when using a sinusoidal modulating wave. Also known as ratio deviation.
References in periodicals archive ?
With these guidelines, measurements were conducted in which the following features were subject to change: three heights, two polarizations, eight different settings model, three analysed values the modulation depth M and two different loads 47 [OMEGA] and 2000 [OMEGA].
In this case the modulation depth is m = 0.1 and the OFB is as strong as [K.sub.ex] = 1.45.
The modulation depth of individual elements to hide watermark bits is based on the fixed value or regular formulae/rule.
A 0.1% change in the resonator voltage corresponds to [+ or -]0.1% AM on the carrier, which is corresponding to a modulation depth of 0.1/200 = 0.0005.
The modulation depth of 64% was achieved in the 90-[micro]m-long waveguide.
The spectrum analyzer functionality of both the R&S ZNL and the R&S FPL1000 includes a wide range of spectral measurements such as channel power, adjacent-channel leakage ratio (ACLR), signal-to-noise ratio, spurious, harmonic distortions, third-order intercept point (TOI) and AM modulation depth. Versatile marker functions are also provided.
During this simulation the amplitude of the measured phase signal (at the frequency 500 Hz) and the carrier modulation depth were changing from 0 to 6.28 rad.
For observation of the cyclotron radiation frequency [[omega].sub.c] the modulation depth about one percent is sufficient.
It should be noted that despite the relatively small diffraction efficiency observed in poly-1 [[eta].sub.1] = 0.10% for 514.5 nm and [[eta].sub.1] - 0.19% for 632.8 nm line, the surface grating exhibits quite remarkable grating modulation depth of 30 nm.
Signal generators must be calibrated at regular intervals to maintain their rated accuracy for output level, carrier frequency, modulation depth, modulation frequency and distortion.