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smart transmitters receivers for under water communication seminars report
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Today 208th bangasree super result in west bengal , kolkata
30-03-2017, 11:58 AM
The number of unmanned vehicles and devices deployed underwater is increasing. New communication systems and network protocols are needed to handle this growth. Optical free space underwater communication is designed to increase underwater acoustic communication, especially for short range, mobile and multiuser environments in future underwater systems. Existing systems are usually point-to-point links with strict signaling and tracking requirements. In this work we demonstrate compact transmitters and intelligent receivers for optical communications of free space under water. The receivers have a wide segmented field of vision and are able to estimate the angle of arrival of the signals. The transmitters are highly directional with individually addressable LEDs for electronic beam switching and are able to estimate the water quality of their backscattered light collected by their co-located receiver. Together they form enabling technologies for non-traditional network schemes in swarms of unmanned underwater vehicles.
Underwater Optical free space communication promises the alternative for short links. Considered as point to point. The new optical front proposed the concept of intelligent transmitters and receivers. Smart Receivers is able to detect the arrival angle of the signals. Intelligent transmitters electronically direct the output beam to a particular direction. Estimate the water quality of the scattered posterior light. The advantages are non-mechanical aiming and tracking in a moving underwater vehicle. Provide sensory information to underwater vehicles. The multi-user multi-user spatial diversity system allows simultaneous reception from two transmitters not located in the same location. It monitors the optical backscatter while the transmitter is active. Beam attenuation coefficient: atio of absorbed or dispersed energy of an incident power per unit of distance. Single dispersion albedo ratio of the dispersion coefficient to the beam attenuation coefficient.
Smart receivers
The goal is to develop an almost omni-directional system that reduces point-and-click requirements. The characteristics are the increase of FOV and the estimation of the angle of arrival. 3-D spherical array of lenses all centered on a 2D matrix photodiode array. A prototype built with seven lenses and seven photodiodes.
Lens Receiver - Research in the field of indoor wireless optics in the use of spherical photodiode matrices to increase FOV. Existing front optical matrices use: - Photodiode arrays without lenses, individual lenses with multiple photodiodes and multiple lenses that focus on separate photodiodes. The received light intensity can be used to estimate the angle of light arrival.
Combination of photodiode output - Connect the photodiode array in parallel. An ideal combination technique to maintain bandwidth, minimize noise and maximize SNR. Linear diversity combing techniques are Equal Gain Combination (EGC) and Maximum Selection Combination (SEL).
The characteristics of intelligent transmitters are increased directionality and electronic beam switching. The design consists of a truncated hexagonal pyramid with seven LEDs. Each LED is coupled with its own lens that converges the wide LED FOV to a narrower beam in a particular direction.
Characterization of the receiver lens photodiode array - Experiments were performed for the target receiver in all directions and intensities were observed in all the photodiode outputs stored as a function of the spherical coordinates. A system of bread and rotation. Built using digital servos.Seven digitized amplified photodiode outputs using 8-channel digitizer.
The results show that the design is also capable of acting as an intelligent system. The backscatter estimation experiment demonstrates a linear relationship between the return beam intensity and the channel attenuation coefficient. Smart receivers increased the field of view capability to estimate the angle of arrival. Intelligent transmitters allow the electronic direction of the switched beam.
Underwater Optical free space communication promises the alternative for short links. Considered as point to point. The new optical front proposed the concept of intelligent transmitters and receivers. Smart Receivers is able to detect the arrival angle of the signals. Intelligent transmitters electronically direct the output beam to a particular direction. Estimate the water quality of the scattered posterior light. The advantages are non-mechanical aiming and tracking in a moving underwater vehicle. Provide sensory information to underwater vehicles. The multi-user multi-user spatial diversity system allows simultaneous reception from two transmitters not located in the same location. It monitors the optical backscatter while the transmitter is active. Beam attenuation coefficient: atio of absorbed or dispersed energy of an incident power per unit of distance. Single dispersion albedo ratio of the dispersion coefficient to the beam attenuation coefficient.
Smart receivers
The goal is to develop an almost omni-directional system that reduces point-and-click requirements. The characteristics are the increase of FOV and the estimation of the angle of arrival. 3-D spherical array of lenses all centered on a 2D matrix photodiode array. A prototype built with seven lenses and seven photodiodes.
Lens Receiver - Research in the field of indoor wireless optics in the use of spherical photodiode matrices to increase FOV. Existing front optical matrices use: - Photodiode arrays without lenses, individual lenses with multiple photodiodes and multiple lenses that focus on separate photodiodes. The received light intensity can be used to estimate the angle of light arrival.
Combination of photodiode output - Connect the photodiode array in parallel. An ideal combination technique to maintain bandwidth, minimize noise and maximize SNR. Linear diversity combing techniques are Equal Gain Combination (EGC) and Maximum Selection Combination (SEL).
The characteristics of intelligent transmitters are increased directionality and electronic beam switching. The design consists of a truncated hexagonal pyramid with seven LEDs. Each LED is coupled with its own lens that converges the wide LED FOV to a narrower beam in a particular direction.
Characterization of the receiver lens photodiode array - Experiments were performed for the target receiver in all directions and intensities were observed in all the photodiode outputs stored as a function of the spherical coordinates. A system of bread and rotation. Built using digital servos.Seven digitized amplified photodiode outputs using 8-channel digitizer.
The results show that the design is also capable of acting as an intelligent system. The backscatter estimation experiment demonstrates a linear relationship between the return beam intensity and the channel attenuation coefficient. Smart receivers increased the field of view capability to estimate the angle of arrival. Intelligent transmitters allow the electronic direction of the switched beam.
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