https://padlet.com/hazimbaik/qqgs18b2cxo3 Assignment padlet en-us 2017-09-17 11:35:01 UTC 2025-10-09 16:34:50 UTC hello@padlet.com hazimbaik https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188215651 hello samuel, firstly we have to propose  operating wavelength, minimum received power, and minimum transmitted power 

]]> 2017-09-17 11:39:39 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188215651 https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188250824 In designing the underwater optical wireless system, there are many issues that are to be considered. Since water channel is highly attenuating for Ultrasound and RF, optical signal is a suitable candidate. However, the choice of wavelength depends on the water characteristics. Moreover in designing the optical transmitter system the modulation scheme that can perform better is to be studied. This paper presents the performance of optical wireless communication system based on the water type, wavelength choice, photon detector sensitivity and modulation technique and enable one to design an optimum underwater wireless optical communication system. In particular, we contrast the performances of On-Off keying, Pulse Position Modulation and Differential PPM, when a PIN and avalanche photodiode is used at the receiver for different water types.]]> 2017-09-17 17:56:45 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188250824 https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188251328 I think we shall propose 1550 nm for the wavelength as it is the most widely used wavelength in optical communication systems.

]]> 2017-09-17 18:01:47 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188251328 https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188252379 The transmission data rate of a digital fiber optic communication system is limited by the rise time of the various components, such as amplifiers and LEDs, and the dispersion of the fiber. The cumulative effect of all the components should not limit the bandwidth of the system. The rise time tr and bandwidth BW are related by   BW = 0.35/tr 
This equation is used to determine the required system rise time.]]> 2017-09-17 18:12:51 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188252379 https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188252758 Look through this and let me know. We'll choose the right parameters for the assignment. See ya!]]> 2017-09-17 18:16:21 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188252758 hazimbaik https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188258622 Okay, so I add a bit for the power budget of the optical link..

Considering a simple point-to-point-link (without amplifier), we find the following component power losses  k=Pout/Pin: - Attenuation losses  of the fiber (proportional to the fiber length L,  kfaser=e-αL) - Coupling losses (input)  Laser-Fiber  (kLF) - Insertion loss of an external modulator  (kMOD)   (optional) - Total Fiber-Splice losses  (kSPLICE , mostly proportional to L) - Coupling losses (output)  Fiber-Photodetector  (kPD)  - Amplification in optical amplifiers (Gtot)  - Responsivity of the photodiode  (R)  Ps,in is the modulated optical power emitted by the source. We determine the power on the receiving photodiode as Pout.
  Depending on  
 1) the requested BER 2) the necessary signal bandwidth Bch  
3) and the noise properties of the receiver  the receiver is characterized by its sensitivity , resp. a minimal optical power Prec,min required at its input (Pout> Prec,min). 

]]> 2017-09-17 19:19:00 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188258622 hazimbaik https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188258814 Three basic types of fiber optic cable are used in communication systems:  
1. Step-index  multimode 
2.Step-index single mode 
3.Graded-index ]]> 2017-09-17 19:20:54 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188258814 hazimbaik https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188259180 ok because low attenuation and speed can go 1.2gbps or 2.4gbps


]]> 2017-09-17 19:24:15 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188259180 hazimbaik https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188259495 detector type, fiber type, amplifier type, and number of connector.]]> 2017-09-17 19:26:40 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188259495 hazimbaik https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188259625 DETECTOR
we use PIN as it is very low noise sensitive to light.

FIBER TYPE
making them useful for all systems using glass fiber single mode

AMPLIFIER TYPE
transimpedance amplifiers in power meters

CONNECTOR
we use limited amount of connector to reduce noise


]]> 2017-09-17 19:27:52 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188259625 hazimbaik https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188261441 for fiber i think i wanna use single mode because:

• Increase bandwidth capacity.
• Limited Data Dispersion & External Interference. The single input mode allows SMF to limit light scattering, which in turn reduce light waste and increase data transmission data.
• Fast Transmission Speed.

]]> 2017-09-17 19:45:08 UTC https://padlet.com/hazimbaik/qqgs18b2cxo3/wish/188261441