Tag Archives: wifi

Wi-Fi 5.0 to Wi-Fi 7.0

Both on smartphones and in living rooms, the audio & video streaming revolution is producing an insatiable demand for speed and bandwidth. To satisfy this demand, in the early 2010s, we had the Wi-Fi 5. However, this lasted only for a decade or so, because by then, consumers had bidirectional video applications such as Webex, WhatsApp, and other social media uploads like TikTok. These had begun to alter not only the consumer landscape but also that of the enterprise.

That led to the catapulting of Wi-Fi 6 to the arena for better management of the huge traffic of streamlining wireless transmissions. This was followed by Wi-Fi 6E which literally extended the benefits of its predecessor with the availability of the 6 GHz band. The pandemic of Covid-19 in 2020 was the moment for Wi-Fi 6 and Wi-Fi 6E, as is evident from the 1+ billion chips of Wi-Fi 6 and Wi-Fi 6E that Broadcom shipped in the past three years.

And still, the demand for higher bandwidth and speed continues only to increase. A recent study has shown that consumer spending on games has increased by 40%. This involves not only devices operating at higher speed, but also the use of newer technology like AR or augmented reality and VR or virtual reaility headsets as new gaming devices. While these devices demand unprecedented levels of immersion while playing, they also call for deterministic and reliable wireless data.

So, we are now moving towards Wi-Fi 7. It has the ability to incorporate 320-MHz channels into the 6 GHz band and employ the 4096-QAM modulation technique, thereby effectively doubling the channel bandwidth. Additionally, it employs better technologies for lowering latency and bolstering determinism. These include AFC or automatic frequency coordination and MLO or multi-link operation.

Wi-Fi 7 comes with spectrum flexibility spanning three bands. However, the critical role is played by the incorporation of 320 MHz channels into the 6GHz band for doubling the speed. For boosting the coverage and the overall network performance, there is the 4096-QAM technique that plays a crucial role.

Wi-Fi 7 can rapidly aggregate channels in congested, high-density networks. This is due to its MLO or multi-link operation that significantly improves its deterministic performance. By rapidly switching traffic among several channels, Wi-Fi 7 can drive greater capacity, thereby facilitating commercial-grade QoS or quality of service in its networks.

Another technology that Wi-Fi 7 utilizes is AFC or automatic frequency coordination. This technique allocates optimum spectrum, thereby enabling high-power access points and extending the 6 GHz range outdoors and indoors. According to Broadcom, its Wi-Fi 7 designs with AFC are capable of 63 times greater transmitting power. This helps not only to extend the range but also the coverage of the 6 GHz band in use.

Therefore, with its immense focus on speed, latency, and determinism, Wi-Fi 7 has entered our lives and is here to stay. According to the forecast of industry technology analysts, revenue from Wi-Fi 7 will supersede that from any other Wi-Fi technology so far in the next five years.

Connect with a New Type of Li-Fi

Many of us are stuck with slow Wi-Fi, and eagerly waiting for light-based communications to be commercialized, as Li-Fi promises to be more than 100 times faster than the Wi-Fi connections we use today.

As advertised so far, most Li-Fi systems depend on the LED bulb to transmit data using visible light. However, this implies limitations on the technology being applied to systems working outside the lab. Therefore, researchers are now using a different type of Li-Fi using infrared light instead. In early testing, this new technology has already crossed speeds of 40 gigabits per second.

According to the Li-Fi technology, a communication system first invented in 2011, data is transmitted via high-speed flickering of the LED light. The flickering is fast enough to be imperceptible to the human eye. Although lab-based speeds of Li-Fi have reached 224 gbps, real-world testing reached only 1 gbps. As this is still higher than the Wi-Fi speeds achievable today, people were excited about getting Li-Fi in their homes and offices—after all, you need only an LED bulb. However, there are certain limitations with this scheme.

LED based Li-Fi presumes the bulb is always turned on for the technology to work—it will not work in the dark. Therefore, you cannot browse while in bed in the dark. Moreover, as in regular Wi-Fi, there is only one LED bulb to distribute the signal to different devices, implying the system will slow down as more devices connect to the LED bulb.

Joanne Oh, a PhD student from the Eindhoven University of Technology in the Netherlands, wants to fix these issues with the Li-Fi concept. The researcher proposes to use infrared light instead of the visible light from an LED bulb.

Using infrared light for communication is not new, but has not been very popular or commercialized because of the need for energy-intensive movable mirrors required to beam the infrared light. On the other hand, Oh proposes a simple passive antenna that uses no moving parts to send and receive data.
Rob Lefebvre, from Engadget, explains the new concept as requiring very little power, since there are no moving parts. According to Rob, the new concept may not be only marginally speedier than the current Wi-Fi setups, while providing interference-free connections, as envisaged.

For instance, experiments using the system in the Eindhoven University have already reached download speeds of over 42 gbps over distances of 2.5 meters. Compare this with the average connection speed most people see from their Wi-Fi, approximately 17.5 mbps, and the maximum the best Wi-Fi systems can deliver, around 300 mbps. These figures are around 2000 times and 100 times slower respectively.

The new Li-Fi system feeds rays of infrared light through an optical fiber to several light antennae mounted on the ceiling, which beam the wireless data downwards through gratings. This radiates the light rays in different direction depending on their wavelengths and angles. Therefore, no power or maintenance is necessary.

As each device connecting to the system gets its own ray of light to transfer data at a slightly different wavelength, the connection does not slow down, no matter how many computers or smartphones are connected to it simultaneously.

Wi-Fi or Li-Fi, What Should You Choose?

Although difficult to believe, but Wi-Fi is running out of steam, or more technically speaking, running out of spectrum. With almost all devices connected with Wi-Fi, our consumption of ever-increasing amounts of information is actually pushing the capacity of Wi-Fi to handle data, to its limits.

Presently, we use radio waves for transmitting information using Wi-Fi, but this method has its limits and it can only transfer so much at a time.

According to the latest estimates, by 2019, we will be exchanging roughly 30-35 quintillion bytes of data each month. We are already consuming huge chunks of radio frequencies and these are heavily regulated. That means Wi-Fi will be starved of bandwidth as data transfer amounts shoot up.

However, work is already underway at providing better technology for increased data transfers. Light Fidelity or Li-FI is showing great promise using light waves to transmit information. Scientists at Tallinn, Estonia, have conducted field tests to achieve speeds of 1GB per second. Although that is only about 100 times faster than traditional Wi-Fi, scientists in their labs claim to have achieved speeds up to 224 GB per second.

Apart from limited capacity, Wi-Fi arrangements are notoriously inefficient. For example, the base station responsible for generating the radio waves works only at about 5 percent efficiency, with the major part wasted as heat. A second part of the problem involves security, as Wi-Fi can penetrate solid objects such as doors and walls, raising concerns for those transmitting sensitive data.

Although light waves are a part of the same electromagnetic spectrum to which radio waves also belong, the difference lies in their wavelengths. Light waves use wavelengths more than 10 thousand times smaller than the wavelengths of radio waves. That means light waves have the capacity to carry enormous amounts of information as compared to radio waves, a fact already established by improved data transmission rates using fiber-optical technology.

However, Li-Fi uses a slightly different method of transmitting data. It works by flashing an LED light on and off at incredibly high speeds when sending data to a receiver. This is essentially sending binary code, only at ultra-high speeds. You will not see any flashes because the LED switches so fast. The communication is primarily line-of-sight, as light from the LED will not penetrate walls and other solid structures. That makes the technology endearing to those looking for security. A person sitting on the other side of the wall cannot eavesdrop on communication using Li-Fi, as they can with the one using Wi-Fi technology.

We already use illumination devices in our homes, and this could double up as potential communication devices as well. What is necessary is to fit a small microchip to every light bulb to convert it into a wireless data communication hub, while also providing the necessary illumination. In other words, we already have the infrastructure in place. The LED bulbs in use in our homes and offices, with some tweaking, can work as incredibly high-speed high volume data transmission and receiving devices.

How do Airplanes Offer Onboard Wi-Fi?

Not long ago, air travel meant you had to switch off your phone and other electronic devices carried. Even for long-distance air travel, people had to put up with in-flight magazines and movies for entertainment. Fortunately, changes have been made – with more to come.

Today, people value connectivity more than ever. Passengers admiring aerial views prefer tweeting about their experiences and follow up with pictures – not content with merely complaining about the food to their neighbors. Airlines are responding to such demands and nearly 40% of the US fights now provide in-flight Wi-Fi, as do several international long-haul flights.

Onboard Wi-Fi technology is still in the nascent stages and significant problems abound. Fliers are not happy with the slow speeds and unreliable connection, especially when the cost for each device for a full flight is high. A FlightView survey of 600 US passengers inferred Wi-Fi offered in-flight satisfied only about 28% of business travelers. The key problem lies in the manner an airplane’s onboard Wi-Fi technology works – there are two main routes.

A US provider, GoGo, has a network system of 3G ground stations all across the US. Planes communicate with these stations when flying overhead. Although the system is simple, bandwidth can be as low as 3Mbps for the entire flight, making it inadequate per customer for streaming videos.

The company is now moving over to ATG-4 technology, with planes requiring dual modems and directional antennas. That boosts the total bandwidth to about 9.8Mbps – still not a significant increase. Planes flying over the seas cannot link to ground stations, which further worsens the connectivity.

As an alternative approach, some airlines allow planes to connect via a satellite. Earlier, they used legacy L-band technology, which was slow and rather expensive. Now using the higher-frequency Ku-band satellites is more common as they work at 12-18GHz. Not only does this offer good performance, it is economical as well. For example, the FlyNet system from Lufthansa claims its download speed to the aircraft reaches 50Mbps, even at the middle of the ocean.

Passengers can optionally connect in two ways. For example, OnAir, a telecom company, allows connections via GSM and Wi-Fi. If you are using a mobile phone, turn on your GSM mobile phone network and use it just as you would on international roaming. Your regular phone bill reflects the costs.

Wi-Fi connection within the aircraft depends on the airline’s own rules. You pay for bandwidth, time of use or distance traveled. Most service providers offset operational expenses and cost of technology (bandwidth) against the number of passengers opting for the service. That decides the rate the airline charges its passengers for the service.

Airlines are discovering the future for on-board connectivity lies in moving towards the Ka-band, which works at 26.5-40GHz via satellites – potentially increasing the capacity nearly 100 times that offered by the present Ku-band. According to ViaSat, a satellite company, this can mean offering each passenger a speed of about 12Mbps, while lessening the cost about five times – a significant progress for frequent, long-distance fliers.