The MulteFire Alliance announced the completion of its Release 1.0 specification today (17 January 2017) a little over a year since the organisation was first formed. MulteFire will provide LTE-like wireless performance in unlicensed and shared spectrum using small cells.
The impetus behind the development of MulteFire, created by a largely vendor, cable and mobile operator-driven independent consortium, is that it leverages the superior quality and reliability of LTE, but enables its usage in unlicensed wireless spectrum.
Mazen Chmaytelli, president of the MulteFire Alliance (and a Qualcomm employee) told Wireless: ‘The genesis of the Alliance in December 2015 was to put together like-minded companies to develop an LTE-like air link in unlicensed spectrum. We also looked at how Wi-Fi is deployed and leveraged some of that, and also how Wi-Fi uses the neutral host concept, so MulteFire uses the best of both technologies.’
The end-to-end architecture design and radio air interface provide performance advantages over Wi-Fi, although not as good as ‘pure’ 4G LTE, in terms of: better radio coverage; enhanced capacity; seamless mobility (better cell handover than Wi-Fi); increased robustness; and enhanced security.
Chmaytelli said MulteFire is very suitable for small cell deployment in the 5GHz band, as well as shared spectrum such as the 3.5GHz band, which is available in the USA. It provides enhanced voice and data services, has a longer range than Wi-Fi and less dropped packages.
Crucially, it implements listen-before-talk (LBT) to ensure fair co-existence with other technologies using the same spectrum, as well as co-existence between different MulteFire networks.
The Alliance was keen not to re-invent the wheel, so MulteFire Release 1.0 is based on 3GPP Releases 13 for the downlink (Licensed Assisted Access – LAA) and 14 for the uplink (enhanced LAA).
It defines how LTE operates in unlicensed and shared spectrum. By removing the requirement for an anchor in licensed spectrum (which LTE-U and LAA require), MulteFire enables new use cases and new deployments to take advantage of the benefits of LTE technology.
The specifications include enhancements for operation solely in unlicensed spectrum such as robust procedures for mobility, paging, initial access and efficient uplink control channels. It also defines a neutral host access mode where the same deployment can serve multiple operators, as well as a traditional access mode for a single network operator.
Release 1.0 enables access authentication with or without a SIM card to provide services for subscribers from different types of service providers, including mobile operators. ‘We saw what Wi-Fi had done here,’ said Chmaytelli, ‘so Release 1.0 has a scheme which removes the complexity of authentication.’ It also supports a range of LTE services, including Voice over LTE (VoLTE) and high speed mobile broadband.
Chmaytelli said: ‘MulteFire removes the licensed anchor link dependency, which means anyone who wants to deploy it can do so. The goal is to enable anyone to install their own MulteFire network, as they do with Wi-Fi today. Various technology people in the Alliance worked very hard to close the delta between unlicensed Wi-Fi and LTE, so that anyone familiar with LTE will be familiar with the way MulteFire works.’
‘Neutral host is an important aspect,’ continued Chmaytelli. ‘The reason we don’t see big deployments of cellular small cell LTE networks is because it is single operator play mostly.’ In addition, enterprises and building owners generally prefer to have a multi-operator solution, and MulteFire takes advantage of Wi-Fi’s neutral host architecture to enable this.
‘We will start seeing MulteFire small cells networks on a neutral host basis. There are lots of opportunities for B2C applications here, such hotel chains establishing a network across the globe providing deals with lots of mobile operators, so consumers on these networks can offload onto a MulteFire network,’ said Chmaytelli.
The Alliance argues that MulteFire’s ease of deployment will open up new business opportunities be allowing existing and new market vertical to deploy and benefit from the LTE technology and ecosystem, including: large enterprises; sports and entertainment; healthcare; public venues; IoT; hospitality; public sector; and MNOs, MVNOs, cable and other operators.
While MulteFire will initially operate in the 5GHz band, and 3.5GHz shared band in the US, Chmaytelli explained it will be able to operate in other frequency bands as they become available. ‘We are looking at other possible unlicensed and shared spectrum bands, which is important,’ she said.
The full specifications will be released to the 21 members of the MulteFire Alliance first. ‘They have paid their dues, so they get the first access to it,’ said Chmaytelli. ‘But as we look at the roadmap ahead, we will provide the full specification to everyone else by the middle of 2017.’
The Alliance has also begun working on a certification programme and is looking to establish the framework for devices, consumer electronics, access points and small cells.
Chmaytelli added that we should be seeing MulteFire trials underway by late 2017.
A new white paper provides a detailed technical description of MulteFire technology and is available at http://www.multefire.org/white-papers/.