What is subcarrier intensity modulation?
Subcarrier intensity modulation with direct detection is a modulation/detection technique for optical wireless communication sys⁃ tems, where a pre⁃modulated and properly biased radio frequency signal is modulated on the intensity of the optical carrier.
What is meant by intensity modulation?
: modulation in which the brightness of the light displayed on a cathode-ray tube varies with the intensity of the signal.
What is intensity modulation direct detection?
Intensity modulation and direct detection (IM/DD) is a cost-effective optical communication strategy which finds wide applications in fiber communication, free-space optical communication, and indoor visible light communication.
What is intensity in optical fiber?
Intensity (Amplitude) Sensors. In this case, the signal to be measured (the measurand), intensity. (amplitude) modulates the light carried by an optical fiber. For this. class of sensors a normalized modulation index (m) can be defined.
What is subcarrier in modulation?
A subcarrier is a sideband of a radio frequency carrier wave, which is modulated to send additional information. Examples include the provision of colour in a black and white television system or the provision of stereo in a monophonic radio broadcast.
What is meant by modulation?
Modulation is the process of converting data into radio waves by adding information to an electronic or optical carrier signal. A carrier signal is one with a steady waveform — constant height, or amplitude, and frequency.
What is the difference between analog and digital modulation?
The main difference between analog modulation and digital modulation is in the manner that they transmit data. With analog modulation, the input needs to be in the analog format, while digital modulation needs the data in a digital format.
What are the purposes of direct detection receiver?
The direct detection receiver in our definition is one that recovers the communicated data from the intensity (i.e. absolute square value) of the received electric field, while using a single photo- diode.
Which type of fiber is used for long distance transmission?
Single Mode fibers
Single Mode fibers are used for high speed data transmission over long distances. They are less susceptible to attenuation than multimode fibers.
How does a subcarrier work?
xRDS is a system with which broadcasters can multiply the speed of data transmission in the FM channel by using further normal RDS subcarriers, shifted into the higher frequencies of the FM multiplex. FMeXtra on FM uses dozens of small COFDM subcarriers to transmit digital radio in a fully in-band on-channel manner.
What is subcarrier in 5G?
In 5G NR, subcarrier spacing of 15, 30, 60, 120 and 240 KHz are supported. The numerology (u = 0) represents subcarrier spacing of 15 kHz which is same as LTE. And as you see in the second column the subcarrier spacing other than 15KHz, for 5G NR.
How is subcarrier intensity modulation ( Sim ) formed?
Subcarrier intensity modulation In this study, Subcarrier Intensity Modulation (SIM) is considered as modulation scheme. SIM is formed by sinusoidal signal pairs and a DC signal which makes total electrical signal positive all the time [ 15 ].
How is subcarrier intensity modulation used in VLC?
In this paper, subcarrier intensity modulation (SIM) is investigated for multiple-input multiple-output (MIMO) visible light communication (VLC) systems. A new modulation scheme called DC-aid SIM (DCA-SIM) is proposed for the spatial modulation (SM) transmission plan.
Which is the best definition of intensity modulation?
From Wikipedia, the free encyclopedia In optical communications, intensity modulation (IM) is a form of modulation in which the optical power output of a source is varied in accordance with some characteristic of the modulating signal.
How is a DC signal formed in a subcarrier?
It is formed from sinusoidal signal pairs and a DC signal which makes total electrical signal positive at all times. At the receiver side, DC content of the signal is filtered by the bandpass filter and sinusoidal parts of the signal are demodulated. Demodulation process is performed on the in-phase and quadrature part of the signal.
