Recently, researchers have demonstrated a new wireless technology using lasers to provide internet connections at over 360Gbps. What does this mean for Wi-Fi, and could lasers be the future of internet?
The Challenge With Wi-Fi and Energy
Wi-Fi is a fantastic technology, and has really defined portable computing. With the use of Wi-Fi, a user can have access to the internet, connect to other devices, and even share files between different machines.
However, for all the positives that Wi-Fi brings, there are some real challenges that it faces. The first, and most obvious, is that Wi-Fi is very power hungry. While this is not an issue when Wi-Fi is used in a stationary location, such as a home office, this can quickly lead to reduced battery life for devices that need to operate remotely.
The second challenge that Wi-Fi faces is its speed. While Wi-Fi is able to achieve very high data rates, newer technologies such as 5G are starting to suffer from interference and range issues. This can make it difficult for Wi-Fi to penetrate walls and spread throughout a living space, which is why many Wi-Fi networks require repeaters to help with signal strength.
The third challenge that Wi-Fi faces is the sheer number of Wi-Fi networks currently in use, leading to a problem called “Wi-Fi starvation”. If there are too many Wi-Fi networks in a given area, it can be difficult for a device to find an open frequency to connect to.
Researchers Break 360Gbps Barrier Using Lasers
A major breakthrough in wireless technology could see internet speeds significantly increase while reducing energy consumption in wireless technology by eliminating the use of radio waves in favour of light. The new technology uses a tiny chip with dozens of miniature lasers that can transmit massive amounts of data simultaneously, and initial tests of the technology have seen speeds exceeding 360 gigabits per second.
The new technology, called optical wireless communication, provides more available bandwidth compared to existing Wi-Fi technologies, does not interfere with existing wireless systems, and can be directed with high precision. The new technology is based on a 5x5 array of vertical-cavity surface-emitting lasers (VCSELs) which are efficient, can operate at high speeds, and can be manufactured in large arrays using standard semiconductor fabrication techniques. Each laser in the array can be controlled independently, and transmit its own stream of data.
The researchers were able to achieve data rates in excess of 360 gigabits per second over a two-meter optical link using 21 active lasers with data rates between 13 and 19 gigabits per second. The researchers also developed an optical system that prevents overlap and interference with other beams. The lenses used in the system organise the beams into a structured grid of square illumination areas that ensure each beam illuminates a specific region of space with minimal overlap.
The researchers compared the energy consumption of the optical wireless system with that of typical Wi-Fi systems to demonstrate the energy efficiency of the new technology. According to the researchers, the energy use of the optical wireless system was approximately 1.4 nanojoules per bit of transmitted data, which is approximately half that of leading Wi-Fi technologies under similar conditions.
Are Lasers Really The Future?
Lasers are excellent for use in wireless communication due to their ability to provide high speed communications at long ranges, and they also lack the interference issues that Wi-Fi suffers from. However, due to their requirement for a line of sight, they are far from trivial to deploy, and as such any light-based wireless system would require tracking and steering.
Various frequencies of light can be used to increase bandwidths, but this introduces its own range of issues, including the need for similar but separate frequencies, ability to control these frequencies with precision, and eliminating interference. Furthermore, the light used cannot be visible as this may cause issues with people in the space.
Overall, what the researchers have demonstrated is really impressive, but for the time being, Wi-Fi will remain the most viable technology.
