Lately, the concept of laser communications has been a popular topic as they provide solutions for the ever increasing bandwidth needs, which are highly in demand today. Here is more info about this concept.
Though lasers have been used for several applications, the field that has received major attention is the feasibility of using lasers for developing a high density communication system.
What is Laser Communication System?
A laser communications link is a wireless connection via the atmosphere. Though it is not a common practice of amateur communication system, it does pose several technical challengesthat have fascinated talented people since years.
Concept of Working of Laser Communications
Laser communication systems work similar to fiber optic links, except for the difference that the beam is communicated via free space. It is necessary that the transmitter as well as receiver be placed in line-of-sight conditions, but they do eliminate the need for buried cables and broadcast rights. Signal transmission is carried out using either a laser diode or high power LED. The frequency used for the transmission of signals is the range close to the infrared spectrum. Two parallel beams of laser lights are used- one for transmitting signals and one for receiving signals.
Advantages and Disadvantages
As seen in the previous section, laser communication systems eliminate the need for buried cables and broadcast rights. Since these systems work near the infrared spectrum, they do not require government licensing or payment of spectrum fees. Moreover, the links can be deployed quickly as radio interference studies are not essential. The narrow beam-width of laser prevents its interference with other communication links of this kind. The laser communication systems are faster than other modes of communications with a speed greater than 1 GBps. So, it surpasses LAN or wireless LATheN completely.
However, there are also few advantages of laser communication links, the main one being the need for direct line-of-sight.Sometimes, the events may be unavailable and there may be short interruptions that may last from few hours to few days. Though laser beams can be transmitted through glass surfaces, the light intensity is decreased for each glass surface because of the combination of refraction and absorption, thus bringing down the operational distance of the link.
Applications of Laser Communication Links
The applications of laser communications can span up to a distance of around 6 kilometres at low bitrates depending on the climatic zones; these links are protocol transparent permitting broadcasting of digital computer data, multiplexed data, VOIP, and video. Hence, laser communications are useful for temporary connectivity requirements such as sports events, university and corporate campuses, military operations, or disaster events.
Based on the latest news in the field of laser communications, we can conclude that the great prospective of laser as a communication system with high density is not yet materialized. Though there is a great deal of research done in the field and several hurdles have been overcome, the basic issue of devising an appropriate transmission system is still a quandary. As of now, cable and microwave are still the leaders for communication.