The Weightless Special Interest Group (SIG) announced the launch of Weightless-N, a breakthrough and complementary open standard for Internet of Things (IoT) today (17 September 2014).
The SIG has already developed one standard, now dubbed Weightless-W, for use in the TV White Space (TVWS) bands. The new Weightless-N standard will enable IoT applications to use licence exempt frequency spectrum.
The vision of the Weightless SIG is to deliver the wide-area machine connectivity standard that enables the 95% of the IoT opportunity denied by the high cost and power consumption characteristics of traditional cellular alternatives.
Today’s announcement delivers on this vision and complements the existing Weightless-W standard through extension into licence exempt frequency spectrum.
Enabling 50 billion connected devices
Commenting on today’s announcement, Professor William Webb, CEO of the Weightless SIG, said: ‘Enabling the vision of 50 billion connected devices requires chipset costs below $2, battery life of 10 years or more and a range of 5km or more to ensure ubiquitous coverage from a low cost network.’
He added: ‘The current Weightless standard delivers on this promise using the TV white space spectrum and provides a feature rich solution, but is subject to regional licensing limitations. Weightless-N aligns with Weightless values and offers geographical ubiquity, right now.’
TV white space is not available everywhere and there are some use cases where the full feature set of Weightless-W, which works in TVWS, is unnecessary. For this reason the Weightless SIG took the decision to commence development of a variant of the current standard termed Weightless-N.
Two Weightless variants
The two variants of the Standard, Weightless-W and Weightless-N will coexist offering benefits to developers and users according to their specific use cases.
Weightless-N will typically be deployed in unlicensed spectrum in the region 800-900MHz, such as the 868MHz band in Europe and the 900MHz ISM band in the US. It is also designed to work in licensed spectrum around these frequencies. These bands are narrower than the TV white space channels and dictate the development of a revised air interface.
This work is underway and being progressed systematically through the Weightless SIG working groups and is anticipated to be completed rapidly. The Weightless SIG welcomes new members to contribute to the evolution of this important new standard and invites proposals from non-members in the drafting of the specification.
The work will be completed in a 3-6 month timeframe and the Weightless SIG is inviting companies that currently have proprietary solutions in this space to engage and adapt these to comply with the new standard. This will enable trials in the first half of 2015 with significant deployments during the second half of the same year.
Global wide area IoT standard
Speaking to Wireless today, Webb explained the thinking behind the development of a second Weightless standard: ‘When we developed Weightless we originally hoped that White Space frequencies would open up rapidly around the world.
‘There haven’t been any significant roadblocks to that, but it has been much slower than we had hoped. The US is opening up, but it is not clear when much of Europe will, for example. So, if we want to claim Weightless is a global standard for wide area IoT networks, we need to look at other bands.’
Webb said that White Space has different properties to the unlicensed bands, so the work done to develop Weightless-W cannot just be shifted over to Weightless-N. ‘We need to build another standard therefore, and we aim to move ahead aggressively to build that standard.’
It may be possible to combine both standards onto one chipset to enable it to be used anywhere in the world, but Webb said: ‘We are already familiar with combining different standards such as Bluetooth, cellular and Wi-Fi onto one chipset, so we could combine both Weightless standards onto one, but it is more expensive to do, so the economics will dictate how that develops.’
Webb believes chipset vendors are more likely to develop the two standards separately, as that is a cheaper, lower risk approach, and later they can decide whether it is worth combining them.
‘One Weightless standard might become more dominant, so that might dictate usage and how it develops,’ Webb pointed out. ‘They have similar attributes in terms of processing and memory requirements, but many IoT applications do not move and so interoperability is not as high a driver. However, having one chipset with both standards on clearly has advantages.’
Webb is optimistic that Weightless-N standard can be written quickly. ‘It depends on how much effort we get from the standards bodies and how many companies get involved – having too many companies involved can hold things back, so development will probably coalesce around a few.
‘The good thing is that we can progress standards much faster than the bigger standards bodies, as we don’t have so many companies involved and have less bureaucracy to deal with.’
He added that one of the advantages the SIG hopes to take advantage of is that there are already a number of chips in the 868MHz band (for car key fobs, for example). These are proprietary solutions, but they take the standard chipset and make a few changes.
‘We hope, therefore, that it won’t require a brand new chipset to start with. Later on we can develop a specific Weightless-N chipset with less external components involved. But the key thing is that there are some proof points in the chip sets already we can make use of,’ said Webb.
The Weightless SIG hopes to announce the companies involved in developing the Weightless-N standard in a few weeks time and to provide more information on the direction it will take.