Modulation pattern for conditioning communication signals for transmission
This article is about the analog modulation. For the digital version, see Phase-shift keying.
Passband modulation
Analog modulation
AM
FM
PM
QAM
SM
SSB
Digital modulation
ASK
APSK
CPM
FSK
MFSK
MSK
OOK
PPM
PSK
QAM
SC-FDE
TCM
WDM
Hierarchical modulation
QAM
WDM
Spread spectrum
CSS
DSSS
FHSS
THSS
See also
Capacity-approaching codes
Demodulation
Line coding
Modem
AnM
PoM
PAM
PCM
PDM
PWM
ΔΣM
OFDM
FDM
Multiplexing
v
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Phase modulation (PM) is a modulation pattern for conditioning communication signals for transmission. It encodes a message signal as variations in the instantaneous phase of a carrier wave. Phase modulation is one of the two principal forms of angle modulation, together with frequency modulation.
In phase modulation, the instantaneous amplitude of the baseband signal modifies the phase of the carrier signal keeping its amplitude and frequency constant. The phase of a carrier signal is modulated to follow the changing signal level (amplitude) of the message signal. The peak amplitude and the frequency of the carrier signal are maintained constant, but as the amplitude of the message signal changes, the phase of the carrier changes correspondingly.
Phase modulation is an integral part of many digital transmission coding schemes that underlie a wide range of technologies like Wi-Fi, GSM and satellite television. However it is not is widely used for transmitting analog audio signals via radio waves.[why?] It is also used for signal and waveform generation in digital synthesizers, such as the Yamaha DX7, to implement FM synthesis. A related type of sound synthesis called phase distortion is used in the Casio CZ synthesizers.
instantaneous phase of a carrier wave. Phasemodulation is one of the two principal forms of angle modulation, together with frequency modulation. In phase modulation...
Continuous phasemodulation (CPM) is a method for modulation of data commonly used in wireless modems. In contrast to other coherent digital phasemodulation techniques...
Modulation is defined as the process by which some characteristics like amplitude, frequency, and phase of a carrier signal are varied in accordance with...
digital modulation scheme or amplitude modulation (AM) analog modulation scheme. The two carrier waves are of the same frequency and are out of phase with...
needed] Frequency modulation and phasemodulation are the two complementary principal methods of angle modulation; phasemodulation is often used as an...
angle modulation, in which either the frequency of the carrier wave is varied, as in frequency modulation, or its phase, as in phasemodulation. AM was...
comprises frequency modulation (FM) and phasemodulation (PM), and is based on altering the frequency or the phase, respectively, of a carrier signal to...
is defined differently in each modulation scheme. Amplitude modulation index Frequency modulation index Phasemodulation index This article includes a...
became standard practice. Digital FM synthesis (equivalent to the phasemodulation using the time integration of instantaneous frequency) was the basis...
electrical detuning of the antenna resonance circuit and hence a measurable phasemodulation of the received signal. When the maladjustment is too large, the transmitter...
method Interactive phase distortion is much more similar to the aforementioned phasemodulation, rather than a direct evolution of phase distortion; see...
idea, adding phasemodulation to the WWVB carrier, in 2012. This requires no additional transmitters or antennas, and phasemodulation had already been...
convenient measure of the linearity of the phase with respect to frequency in a modulation system. For a modulation signal (passband signal), the information...
Phase offset modulation works by overlaying two instances of a periodic waveform on top of each other. (In software synthesis, the waveform is usually...
In order to address the inability to separate white phasemodulation from flicker phasemodulation using traditional Allan variance estimators, an algorithmic...
with potential energy transfer. Cross-phasemodulation (XPM), where one wavelength of light can affect the phase of another wavelength of light through...
transmitted by phase-modulating the carrier by ±1 radian in 0.1 s every second except the 59th second of each minute. This modulation pattern is repeated...
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