The process of building each new mobile standard begins years before it is put into industrial use, and once done, those standards will remain in place in various forms for a decade or more. With 5G, we have to build a standard that will be in use in 2030 and beyond. “5G” is something of a misnomer: the standard doesn’t exist yet. It takes months, may be years, before it is finally defined. Meanwhile, industries, governments, and scholars are working on the technologies that will form the standard, but today, 5G is purely a concept, and may not be expected to reach the real-world before the next five years. The standards may not be ready for use, but the stake-holders have got a fair idea about its expected deliverables.
So far, three main criteria for the 5G standard have been established:
- It should be capable of delivering a 1Gbps downlink to start with and multi-gigabits in future.
- Latency must be brought under one millisecond.
- It should be more energy efficient than its predecessors (exact parameter not decided yet).
The agreement on basic use cases has also been reached in industrial circles for 5G. Machine to machine communications is one such case. 5G should enable the internet of things (IOT), the future where all our online-enabled objects will quietly pass on the data to our technological entities of choice. Facilitation to the use of mobile networks by connected or autonomous cars, remotely controlled industrial robots, tele-health systems and smart city infrastructure are also all expected to figure large in 5G thinking.
There are more recognizable experiences, too, that are often cited as imminent uses for 5G — the ability to download 4K or 8K video at speed, for example — and occasionally those that are more forward-looking. Despite this emerging understanding of what 5G should look like, there is still a lot to argue around the standard, including which should be the appropriate technology as part of it.
Every new mobile standard brings with it calls from operators for more spectrum. The proposed 5G standard is also not immune to it. If mobile operators want to deliver more and more facilities, they are obviously going to call for more and more wireless spectrum to achieve it.
Now, every improved feature or services, government needs to identify the spectrum requirements, its availability and proper allocation to operators. Post-allocation, Government needs to ensure all the obligations are met and proper clean up procedures are followed by the operators. Now, with the proposed 5G, governments needs to identify the spectrum for it. As per expert knowledgeable sources from wireless industry, there is no enough spectrum available for ambitious overloaded applications of 5G. Specially when roaming services involve, situation become even more critical.
One solution to this severe spectrum crunch could be to look to other frequency spectrums, not used till now. It mean moving towards higher microwave frequency bands such as 6GHz, 28GHz or even towards millimetre waves (above 30 GHz). Utilizing these bands is both thrilling as well as challenging areas of 5G development. As we go higher in frequency, from microwave to millimeter range, convergent properties start taking precedence over multi-directional properties. This will result in comparatively more uni-directional communication than currently available omni-directional one. This will require drastic changes in currently installed wireless communication systems. Another identified problem was attenuation in millimeter waves that makes them unable to travel long distances.
Recent breakthroughs have helped to crack this crucial bottleneck. It is observed that at higher frequencies (30 GHz and beyond) the attenuation factor start playing lesser role and the rf channel behaves remarkably similar to cellular, microwave frequencies without any additional atmospheric loss. It means mm waves don’t suffer attenuation except acceptable free space propagation.
Another blocker of mm wave utility was “rain attenuation” more specifically the disruptive rf signal behavior while raining outdoors. This phenomenon has caused disruptions in financial services industry and DTH services, where mm waves are frequently used. But, according to researchers at NYU*, the attenuation is in the region of 1.4 dB over 200m. It means the attenuation is there, but it is not really at high enough level to lose sleep about. This paper further concludes rain attenuation will present a minimal effect on the propagation of mm-waves for small distances (less than 1 km), at 28GHz to 38GHz for small cells. Such attenuation losses may further be compensated by using directional antennas.
Such academic research has given extremely encouraging and futuristic indications. Hence, once rejected millimetre waves are back on the table again. For further extensive research, enormous amount of funding is required to utilize these scientific breakthroughs for commercial exploitation. But the important question is “Are mobile industry or governments ready for the funding?” Or let me rephrase the question in more appropriate way “Is proposed 5G with IOT, M2M etc. provides enough attraction, viability or motivation to investors and stake-holders?”.
According to figures from the GSM Association, operators will spend $1.7 trillion dollars on their LTE networks between 2014 and 2020, and clearly they will want to see fair returns on that investment before they begin rolling out any replacement. Another factor is any replacement pricing model with enhanced features requires freebies to be provided to customers. When many carriers switched to 4G, they had to their customers’ access for free, with an offer of 5GB of 4G data at the same cost as 5GB of 3G data, hoping that the customers enjoying better speeds would utilize more data, and so move to progressively expensive packages.
Still, the attractions are huge. New segmented pricing model- offering data tiered by speeds, will ensure better returns. Apart from it, with new generation of mobile technology, the need for a new smartphone will naturally arise. This will be another way for operators to extract more cash-flow from their customers. Another major attraction is the mobile industry outreach due to proposed IOT technology of machine-to-machine interactions will bring range of dedicated customers as well as services who have traditionally never took interests in networking with ease of mobility. It will open the door for range of new revenue earnings options, if backed up with appropriate pricing models.
Last but not the least, “One Gbps speeds is the base line for 5G, multi-gigabits is the aim” is itself not a small sticking point for funds to flow. Consumers, according to industry types, won’t feel the shortage of speed and capacity in foreseeable future (say next hundred years or so..), howsoever much data they are using and wherever they are. There will be no need to replace mobile technology with each passing decade, if 5G networks are built properly,. Only the updates bit by bit would be enough as new requirements and technology, arise.
*Reference: Thedore S. Rappaport et. al. “Millimeter Wave Mobile Communications for 5G Cellular: It Will Work!”, DOI: 10.1109/ACCESS.2013.2260813