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 ?
However, this technique doesn't allow controlling of the desired harmonic order, total harmonic distortion (THD) and modulation index. Another technique is Selective Harmonic Elimination (SHE).
For the purpose of avoiding malfunction on the PI controllers, the one used to determine the electrical frequency, [[omega].sub.e], must operate with lower dynamics than that of the other one used for generating the modulation index m, which corresponds to the normalized amplitude of the AC output voltages.
As the TTP is highly variable across patients and the degree of correlation between the paired failure times is a key feature, Von Hoff [1] proposed to evaluate the growth modulation index (GMI = [TTP.sub.2]/TTP:) instead, so that each patient serves as his/her own historical control.
Booming and rumbling sensation were analyzed and developed in the form of the booming index (BI) and modulation index (MI) as means to express powerfulness of engine sound [10].
Therefore, in the paper, not only the booming index (BI) and modulation index (MI) are developed as the sound metrics of powerfulness and applied to the development of powerful index but also the ratio of order decay based on the spectrum decay is developed as the sound metric of pleasantness and applied to the development of pleasant index of a vehicle.
The frequency modulation index ([m.sub.f]) is as follows
where [v.sub.R], [v.sub.Y], and [v.sub.B] are the three phases, M is the modulation index, and [m.sub.cm] is the common mode signal.
As the phase measurements are only possible in (-[pi], [pi]), when the modulation index and the signal sequence are large, the phase shift ambiguity occurs when the total phase shift is more than 2[pi] when sampling, which may lead to wrong estimation result of the IF.
Parameters Value DC voltage 6.6 kV Output frequency 60 Hz Output inductor 5mH Output resistor 7.5 [OMEGA] Flying capacitor 2200 [micro]F Modulation index 0.95
Parameters Unit Value Base module Tx power dBm 17.6 Tx frequency GHz 10.5 Rx frequency GHz 8.5 AM modulation index % 20 AM conversion gain dB 3.5 FM bandwidth MHz 420 FM sweep frequency kHz 2.5 FM conversion gain dB 61.5 Tag module Rx frequency GHz 8.5 Tx frequency GHz 10.5 Conversion gain dB 32 Antenna (horn) Gain dBi 24 Beam width [degrees] 20 TABLE 3: Comparison of high-accuracy radar systems.
Also the same information is used to look up the control mode (SVPWM vs six-step) and the modulation index reference MI* from the table.

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