First Net is a brand new nationwide US LTE network dedicated for use by First Responders. With a budget of $7 billion and exclusive 20MHz spectrum, this will provide high speed LTE services to around a million professionals. With extensive coverage and lots of spare capacity, First Net have also indicated that others could share their spectrum on a commercial basis. Is this the ideal third party neutral host we’ve been waiting for?
LTE (Long Term Evolution) has undoubtedly won the battle to become the world's 4th Generation radio access technology. It promises speeds of 100's of Mbit/s and includes many features to increase resilience, spectral efficiency and network performance. Small cells have been designed in from the outset, and will be a critical component providing the high speeds and capacity foreseen.
The first LTE small cells were developed independently from 3G products, and we have seen a number of new market entrants who had little or no involvement with earlier 3G femtocells. Chipset vendors such as Broadcom, TI, Fresscale and Cavium have been making great headway. Leading small cell vendors have included LTE in their roadmaps, but are cautious about bringing products to market too early while there remains strong demand for 3G.
The LTE system architecture differs from 3G, without mandating a small cell gateway. This puts more pressure on the core network, with every inter cell handover being handled directly by the core network. Some believe that for larger deployments, especially where indoor/residential is involved, a gateway will be required.
For some insight into what operators are thinking, I attended and reported on the Operator Mindshare session at LTE World Summit 2012, followed by the main LTE event itself.
We also looked at which vendors are developing LTE small cells.
The Small Cell Forum identified SON vendor interoperability to be a common concern with operators and holding back wider LTE Small Cell take-up. Network densification will result in large numbers of Small Cells being deployed ad-hoc and unplanned, making this an critical feature. Substantial progress has been made this year culminating in public operator validation and approval after extensive testing.
Aggregation is being used to meet demand for faster data rates, by combining multiple channels at different frequencies and even different radio technologies. LTE, Wi-Fi and LTE using Wi-Fi spectrum are all actively being developed. We look at the options on offer and consider the tradeoffs.
A new shared spectrum scheme is being introduced in the US at 3.5GHz called CBRS, ideally suited for in-building small cells. It promises to unblock the logjam by opening up new spectrum for almost anyone to use with standard LTE on future mainstream smartphones. What exactly is being proposed, how will it work and where else could this approach be used?
There are many different public safety radio networks used by multiple first responder services today – fire, ambulance, police etc. In the US, each may have its own frequency (VHF or UHF) and dedicated handsets. Europe has adopted TETRA, a common standard similar to GSM. One problem with these specialist systems is that the relatively low volume of product means they are expensive and new features are developed slowly. Handsets can cost $3,000 yet provide basic voice and text only.