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RONJA
RONJA (Reasonable Optical Near Joint Access) is a free-space optical communication system developed in the Czech Republic by Karel Kulhavý of Twibright Labs. Released in 2001. It transmits data wirelessly using beams of light. Ronja can be used to create a 10 Mbit/s full duplex Ethernet point-to-point link. It has been estimated that 1,000 to 2,000 links have been built worldwide.
The basic configuration has a range of 1.4 km (0.87 mi). The device consists of a receiver and transmitter pipe (optical head) mounted on a sturdy adjustable holder. Two coaxial cables are used to connect the rooftop installation with a protocol translator installed in the house near a computer or switch. By increasing the diameter of the lens and transmitter pipe diameter, the range can be extended to 1.9 km (1.2 mi).
Building instructions, blueprints, and schematics are published under the GNU Free Documentation License, with development using only free software tools. The author calls this approach "User Controlled Technology", emphasising their view on the importance of open-source and user-driven software and innovation
The building instructions are very detailed, guiding the builder along the setup. Basic operations like drilling, soldering etc., are explained, along with all technical terms used. Several techniques – drilling templates, detailed checks after soldering, testing procedures – are employed to minimize errors at critical places and help to speed up work. Printed circuit boards are downloadable ready for manufacture, with instructions for a fabrication house (PCB manufacturer).
154 installations, located in multiple European countries and Brazil in South America have been registered into a gallery with partial descriptions, pictures and extra data.
With the brightest variant of Lumileds HPWT-BD00-F4000 LED and 130 mm diameter cheap magnifying glass lenses, the range is 1.4 km (0.87 mi). The dimmer but more affordable E4000 variant of HPWT-BD00 yields 1.3 kilometres (0.81 mi). The speed is always 10 Mbit/s full duplex regardless of the distance.
As an FSO system it requires clear visibility between the transmitter and receiver. If the beam is obscured in a way that introduces too much noise or fully obstructs it, the link will stop working. Typically, problems may occur during conditions of snow or dense fog. One device weighs 15.5 kg (34 lb) and requires 70 hours of building time. It requires an ability to set full duplex manually on the network card or switch to take advantage of full duplex, since it doesn't support autonegotiation. Must be plugged directly into PC or switch using the integral 1 metre (3 ft 3 in) Ethernet cable.
A complete RONJA system is made up of 2 transceivers: 2 optical transmitters and 2 optical receivers. They are assembled individually or as a combination. The complete system layout is shown in the block diagram.
Hub AI
RONJA AI simulator
(@RONJA_simulator)
RONJA
RONJA (Reasonable Optical Near Joint Access) is a free-space optical communication system developed in the Czech Republic by Karel Kulhavý of Twibright Labs. Released in 2001. It transmits data wirelessly using beams of light. Ronja can be used to create a 10 Mbit/s full duplex Ethernet point-to-point link. It has been estimated that 1,000 to 2,000 links have been built worldwide.
The basic configuration has a range of 1.4 km (0.87 mi). The device consists of a receiver and transmitter pipe (optical head) mounted on a sturdy adjustable holder. Two coaxial cables are used to connect the rooftop installation with a protocol translator installed in the house near a computer or switch. By increasing the diameter of the lens and transmitter pipe diameter, the range can be extended to 1.9 km (1.2 mi).
Building instructions, blueprints, and schematics are published under the GNU Free Documentation License, with development using only free software tools. The author calls this approach "User Controlled Technology", emphasising their view on the importance of open-source and user-driven software and innovation
The building instructions are very detailed, guiding the builder along the setup. Basic operations like drilling, soldering etc., are explained, along with all technical terms used. Several techniques – drilling templates, detailed checks after soldering, testing procedures – are employed to minimize errors at critical places and help to speed up work. Printed circuit boards are downloadable ready for manufacture, with instructions for a fabrication house (PCB manufacturer).
154 installations, located in multiple European countries and Brazil in South America have been registered into a gallery with partial descriptions, pictures and extra data.
With the brightest variant of Lumileds HPWT-BD00-F4000 LED and 130 mm diameter cheap magnifying glass lenses, the range is 1.4 km (0.87 mi). The dimmer but more affordable E4000 variant of HPWT-BD00 yields 1.3 kilometres (0.81 mi). The speed is always 10 Mbit/s full duplex regardless of the distance.
As an FSO system it requires clear visibility between the transmitter and receiver. If the beam is obscured in a way that introduces too much noise or fully obstructs it, the link will stop working. Typically, problems may occur during conditions of snow or dense fog. One device weighs 15.5 kg (34 lb) and requires 70 hours of building time. It requires an ability to set full duplex manually on the network card or switch to take advantage of full duplex, since it doesn't support autonegotiation. Must be plugged directly into PC or switch using the integral 1 metre (3 ft 3 in) Ethernet cable.
A complete RONJA system is made up of 2 transceivers: 2 optical transmitters and 2 optical receivers. They are assembled individually or as a combination. The complete system layout is shown in the block diagram.