Table of Contents
What is a symbol in QAM?
The term “symbol” means some unique combination of phase and amplitude. The term M as in M-QAM indicates how many bits are transmitted per time interval or symbol for each unique amplitude/phase combination. The simplest form of QAM is 2-QAM, more commonly called QPSK or quadrature phase shift keying.
Which modulation is used in Bluetooth?
Gaussian frequency-shift keying (GFSK)
Bluetooth Low Energy uses 2 MHz spacing, which accommodates 40 channels. Originally, Gaussian frequency-shift keying (GFSK) modulation was the only modulation scheme available.
What is amplitude modulation?
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In the frequency domain, amplitude modulation produces a signal with power concentrated at the carrier frequency and two adjacent sidebands. Each sideband is equal in bandwidth to that of the modulating signal, and is a mirror image of the other.
How do I implement space vector modulation?
To implement space vector modulation, a reference signal V ref is sampled with a frequency f s (T s = 1/f s ). The reference signal may be generated from three separate phase references using the transform. The reference vector is then synthesized using a combination of the two adjacent active switching vectors and one or both of the zero vectors.
How many degrees of phase angle is required for space vector modulation?
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Note that looking down the columns for the active switching vectors V 1-6, the output voltages vary as a pulsed sinusoid, with each leg offset by 120 degrees of phase angle . To implement space vector modulation, a reference signal V ref is sampled with a frequency f s (T s = 1/f s ).
What is the difference between carrier wave and amplitude modulation?
In this sense, the carrier wave, which has a much higher frequency than the message signal, carries the information. At the receiving station, the message signal is extracted from the modulated carrier by demodulation . In amplitude modulation, the amplitude or strength of the carrier oscillations is varied.