A digital receiver compares the amplified and filtered signal from an equalizer to a threshold level to determine if a pulse is present at a given time slot, with the output voltage above the threshold for a 1 and below for a 0. However, in practice there are deviations from these ideal levels due to noise, interference from adjacent pulses, and incomplete suppression of light during zero pulses. The performance of the receiver is analyzed assuming Gaussian, flat spectrum, and uncorrelated noise sources.
Optical Fiber Communication Part 3 Optical Digital ReceiverMadhumita Tamhane
Current generated by photodetector is very weak and is adversely effected by random noises associated with photo detection process. When amplified, this signal further gets corrupted by amplifiers. Noise considerations are thus important in designing optical receivers.
Most meaningful criteria for measuring performance of a digital communication system is average error probability, and in analog system, it is peak signal to rms noise ratio. ...
Optical Fiber Communication Part 3 Optical Digital ReceiverMadhumita Tamhane
Current generated by photodetector is very weak and is adversely effected by random noises associated with photo detection process. When amplified, this signal further gets corrupted by amplifiers. Noise considerations are thus important in designing optical receivers.
Most meaningful criteria for measuring performance of a digital communication system is average error probability, and in analog system, it is peak signal to rms noise ratio. ...
different types of internal and external noises, s/n ratio, s/n ratio of a tandem connection, noise factor, amplifier input noise, noise factor of amplifiers in cascade (friss's formula).
This presentation covers noise performance of Continuous wave modulation systems; It explains modelling of white noise , noise figure of DSB-SC, SSB, AM, FM system
This presentation covers types of noise in communication system, noise modelling, thermal noise, shot noise, experimental determination of noise figure, noise figure, friss formula with numerical.
LightWave: Using Compact Fluorescent Lamps as SensorssidhantguptaUW
LightWave is a novel sensing technique that can convert ordinary CFLs into sensors of human proximity. This requires no modification of the bulb or instrumentation on the human body. A single sensor installed anywhere in the home converts all CFL lamps in a home into sensors. LightWave can detect human proximity, touches on the lamp shade or the metal base and on the bulb itself. In addition, it can also detect changes in ambient temperature, all with off-the-shelf unmodified CFLs.
different types of internal and external noises, s/n ratio, s/n ratio of a tandem connection, noise factor, amplifier input noise, noise factor of amplifiers in cascade (friss's formula).
This presentation covers noise performance of Continuous wave modulation systems; It explains modelling of white noise , noise figure of DSB-SC, SSB, AM, FM system
This presentation covers types of noise in communication system, noise modelling, thermal noise, shot noise, experimental determination of noise figure, noise figure, friss formula with numerical.
LightWave: Using Compact Fluorescent Lamps as SensorssidhantguptaUW
LightWave is a novel sensing technique that can convert ordinary CFLs into sensors of human proximity. This requires no modification of the bulb or instrumentation on the human body. A single sensor installed anywhere in the home converts all CFL lamps in a home into sensors. LightWave can detect human proximity, touches on the lamp shade or the metal base and on the bulb itself. In addition, it can also detect changes in ambient temperature, all with off-the-shelf unmodified CFLs.
The attached narrated power point presentation mentions the various figures of merit and the types of noise associated with photodetectors. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
The attached narrated power point presentation offers a block level and an elementary level mathematical treatment of optical communication systems employing coherent detection. The material will immensely benefit KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
4. D. R. PERFORMANCE
• Amplified and filtered signal from equalizer is
compared with threshold level , to determine
weather a pulse is available at photo detector
at given time slot or not.
• Ideally
Vout>Vth -when binary 1 present
Vout<Vth -when binary 0 present
5. CONTD….
• In general systems ,deviations from average
value Vout . the main reasons due to this that
are-
1.various noise
2.interference from adjacent pulse
3.light source is not completing during zero
pulse.
6. assumptions
• All noise source are Gaussian in statistics.
• All noise are flat in spectrum.
• All noise sources are uncorrelated.
RECEIVED POWER
