Phase Modulated Signals
Phase Modulated Signals - Related Videos
08:39
Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
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Cited by 3 •
2019
We show how to encode the complex field of laser beams by using a single phase element. A common-path interferometer is employed to mix the phase information displayed into a phase-only spatial light modulator to finally retrieve the desired complex field pattern at the output of an optical imaging system.
06:42
Identifying Kinase Inhibitors that Modulate the Thymocyte Response to Strong TCR Signals
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2025
In this video, we describe a method to identify the small-molecule kinase inhibitors that modulate the apoptosis of self-reactive CD4+CD8+ double-positive immature thymocytes. Apoptosis is induced in the double-positive thymocytes by activating them with anti-CD3- and anti-CD28-coated magnetic beads; this is followed by a small-molecule inhibitor treatment and flow cytometry analysis to detect if the inhibitors modulate the apoptotic marker expression.
02:29
Modulating Sensory Neuronal Signaling in a Mouse Model Using Near Infrared Light
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2025
Source: Zhang, L., et al. Near Infrared (NIr) Light Increases Expression of a Marker of Mitochondrial Function in the Mouse Vestibular Sensory Epithelium. J. Vis. Exp. (2015)This video demonstrates the process of applying NIr light to a shaved mouse scalp to activate vestibular neurons and stimulate superoxide dismutase-1 (SOD-1) production, supporting neuronal function. The procedure highlights NIr therapy as a neuroprotective strategy.
09:51
Single Phase Inverter
0 Views •
2023
Source: Ali Bazzi, Department of Electrical Engineering, University of Connecticut, Storrs, CT. DC power is unidirectional and flows in one direction, whereas, AC current alternates directions at a frequency of 50-60 Hz. Most common electronic devices are designed to run off of AC power; therefore an input DC source must be inverted to AC. Inverters convert DC voltage to AC through switching action that repeatedly flips the polarity of the input DC source at the output or load side for part of...
11:31
Establishment of a High-throughput Setup for Screening Small Molecules That Modulate c-di-GMP Signaling in Pseudomonas aeruginosa
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Cited by 2 •
2016
This article describes the high-throughput assay that has been successfully established to screen large libraries of small molecules for their potential ability to manipulate cellular levels of cyclic di-GMP in Pseudomonas aeruginosa, providing a new powerful tool for antibacterial drug discovery and compound testing.
FAQs
The message amplitude determines how far the carrier phase shifts at a given moment, while the carrier frequency remains the nominal reference. As the message changes over time, the phase follows those changes rather than altering the ideal carrier envelope. This relationship allows the transmitted waveform to represent information through time-varying phase behavior.
The ideal envelope remains constant even though the carrier phase changes. This separates amplitude behavior from information-bearing phase behavior and gives engineers a useful way to inspect signal integrity. Comparing the envelope with the changing phase helps identify whether the waveform is behaving according to the intended modulation principle.
A receiver examines phase changes over time and compares them with a phase reference or successive signal states. That comparison reveals the variations produced by the message. Reliable recovery therefore depends on appropriate synchronization, because an incorrect phase reference can make valid changes difficult to distinguish from other signal behavior.
These factors influence whether the receiver can distinguish intended phase changes and recover the message accurately. Bandwidth analysis shows how the signal occupies transmission resources, noise analysis examines disturbances that may obscure phase information, and synchronization analysis evaluates the receiver’s ability to maintain a useful phase reference throughout communication.
Engineers can first inspect the carrier waveform and its envelope, then track instantaneous phase changes as the message varies. They can next evaluate bandwidth, consider noise effects, and assess synchronization requirements. Finally, they compare the recovered information with the transmitted message to judge signal integrity and communication performance.
They support both analog and digital communication systems. Engineering applications identified for this approach include phase-shift keying, radio links, satellite systems, and wireless networks. In each setting, phase behavior becomes central to transmitting or recovering information while engineers evaluate bandwidth use, noise sensitivity, synchronization, and the integrity of the received signal.
Phase-shift keying applies phase modulation in a digital communication context by representing information through distinct phase states. It differs from an analog message representation because the transmitted information is associated with selected digital phase changes rather than a continuously varying message description. This makes it relevant to wireless networks and other digital engineering systems.