ZigBee – Page 2 – Creative Connectivity

Choosing a Wireless Standard

The first question that most designers ask when adding wireless to their product is “which wireless standard to use?” In some cases, where it is connecting to an existing product, that’s easy to answer. If it’s not, it’s a lot more difficult. It’s one reason I wrote a book about it – to try and help designers answer that question. But another part of the same question is how well the different standards promote themselves as a solution?

This year has seen some major changes within some of those wireless standards. The ZigBee Alliance has lost Benno Ritter – for many years the global marketing face of ZigBee. And the Bluetooth SIG has replaced its Chairman, Mike Foley, as well as its CTO, Andy Glass. Both are interesting moves, as each of these standards is still evolving. ZigBee is taking on smart lighting, home automation and smart metering, whilst Bluetooth is finally seeing Bluetooth Smart appearing in the mainstream. In a recent issue of Incisor magazine, Vince Holton wrote about the loss of passion within the Bluetooth SIG – a sentiment that I’d echo and also extend to some of the other wireless standards. But that’s an opinion formed from being close to these groups. A few years ago I ran to survey to try and see what the general engineering opinion was of the different wireless standards. Prompted by Vince’s article, I thought it would be useful to run the survey again to see what designers think as we approach the end of 2012.

The End of the One Trick Wireless Pony. Or is it?

And then there were none. Last month Silicon Labs acquired Ember – the last independent ZigBee chip manufacturer. It’s good news for the Smart Metering industry as it’s secured a future for Ember, who have become the chip and protocol stack supplier of choice for a large proportion of smart meters, IHDs and home gateways in the market today. It’s not such good news for the investment community, as the $72 million initial consideration from SiLabs is a little short of the $89 million investment that had gone into Ember. But given the fire sales of the other ZigBee start-ups, it’s still not a bad result.

And it could be one of those excellent fits that don’t come along that often. For Silicon Labs, it extends their radio technology into the hotly contested 2.4GHz band, complementing their very capable sub-GHz range of EZRadio PRO chips. It also gives them what I’d consider to be the best ZigBee stack on the market. And it gives Ember what must be a very comforting degree of financial security as well as a ready made range of sub-GHz radios, just at the point where the UK and Japanese smart metering communities are looking at 868MHz.

But it’s not just Ember getting gobbled up. A few weeks later, Samsung quietly acquired Nanoradio – the Swedish specialist in low power Wi-Fi for mobile phones. Both Ember and Nanoradios played the standards card and had essentially become one trick wireless ponies – a fate common to many wireless start-ups. Perversely, CSR did the opposite thing today, by divesting itself of much of its location technology, (which it had acquired from SiRF), to Samsung, who seem to be getting rather good at acquiring bits of wireless technology. In doing so CSR moved itself back closer to its Bluetooth roots.

Although the prospect of an acquisition is the raison d’être of most wireless silicon start-ups, I wonder whether this flurry of activity indicates that we’re nearing an end-game? In which case, what comes next?

Posh Boys push Smart Meters

DECC – the Government department leading the Smart Metering deployment in the UK recently published their latest research on consumer attitudes to Smart Metering. It reports the results of in depth interviews with 120 representative members of the population on their feelings about Smart Meters and IHDs.

The research was conducted in February this year, several months before the Conservative backbencher Nadine Dorries described her Prime Minister David Cameron and Chancellor of the Exchequer George Osborne as “two posh boys who don’t know the price of a pint of milk”. She wasn’t referring to the UK Smart Metering programme, but it was a pretty good description of what these 120 respondents thought of the smart meter deployment, telling researchers that it “sounds like it’s from someone who doesn’t have trouble paying their bills”.

The report is not all bad news. The respondents included people who had received In Home Energy Displays and in general they liked them. They thought they provided real benefits. In contrast, they had difficulty in seeing what the added value of the smart meter was.

I suspect DECC is busy trying to massage the results to make it look as if the survey supported smart metering, helped by some rather ambiguous leading questions. But the content highlights a growing division within the smart metering programme, which is whether it is meant to be there for the benefit of consumers or for the benefit of utilities?

The Cost of Wireless Standards

How much does it cost to produce a wireless standard? And how long does it take? Surprisingly those aren’t questions that are asked very often – probably because most developers are happy to use what already exists rather than starting again from scratch.

In the UK, some members of the smart metering programme have begun asking these questions, potentially for the wrong reasons. They’ve realised that ZigBee – the current front-runner for the UK smart metering deployment, can’t provide the range to cope with every single house or block of flats, and have started wondering about whether it might make sense to start again from scratch.

A few years ago, when I was writing my book on the Essentials of Short Range Wireless I attempted to put some numbers to those questions. It seems an appropriate time to publish them, as the answers are a lot more and a lot longer than most people think.

A UK Roadmap for Smart Metering HANs

One of the eternal complaints about short range wireless is its limited range, particularly when used within homes. Whilst the name “short range wireless” ought to give a clue about the existence of the problem, it doesn’t stop a general level of indignation when a radio signal doesn’t make it through the walls of your house.

Up until now this was mostly an annoyance, largely because it was a personal problem. By that I mean it was an inconvenient truth that individuals discovered when they bought a consumer wireless product, whether that was a Wi-Fi access point, a cordless phone or a mobile headset. As these were generally low cost, discretionary purchases, users either took them back, put them in a cupboard and forgot about them, or worked around the problem by moving the appropriate access point. For the more technically engaged, a raft of companies grew up making repeaters, range extenders, power amplifiers and directional antennae, allowing users to exacerbate the problem by swamping all of their neighbours’ installations.

In the last year people have started to take the middle word of “short range wireless” rather more seriously. That’s come about as governments around the world have mandated deployments of smart meters. Whilst no-one cared too much if a consumer product didn’t work, smart meters are a different kettle of fish. They need to be able to connect with the other components of the smart metering wireless network in the home in order to send consumption data back to the utilities. They have to do that reliably and regularly over a period of many years. And they need to be able to cope with a wide variety of homes – from small bungalows to multi-storey apartment buildings. All of a sudden that “range” word is getting a lot of attention.

The problem is that the wireless standards being considered don’t cover 100% of different homes. Any one standard probably struggles with covering much more than 75% of potential homes. That’s a big problem for regulators and civil servants who have a very black and white view of life – when a mandate says “all”, they assume that means every last home. So what can they do?

PublishedJanuary 25, 2012
7 Comments on In Praise of Cables

For most of the last twenty or so years I seem to have started off the year by writing an article claiming that this would finally be the one when wireless data takes off. It’s nice to see things changing: Wi-Fi is finally starting to move outside internet access for PCs and Phone, Bluetooth Smart is appearing in desirable consumer devices and should trigger an avalanche of connected accessories, and smart metering is bringing ZigBee and Wireless M-Bus into homes as a static PAN. That doesn’t mean that there are not still massive unexplored opportunities in M2M, but it’s good progress.

Instead of the obvious call for more, I’d like to look back at the many advantages of cables. As designers rush into wireless, it’s easy to forget what they’re giving up. Wireless offers new opportunities, but only at the expense of many serious compromises. In this brave new world of wireless it’s apparent that some people are forgetting those compromises. In this and the following article I’m going to look at what they are and then address the misconception that wireless standards can be treated in the same way as wired ones, debunking the common misconception that they follow the OSI model.