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It's great when two high speed technologies come together: High speed trains running at over 300 km/h and high speed Internet access. Thalys, whose trains travel between Paris, Brussels, Amsterdam and Cologne has equipped all of their trains with satellite, Wi-Fi, UMTS and GPRS based high speed Internet access, accessible to passengers via standard Wi-Fi. When I recently traveled on one of those trains, I could hardly wait to get on board to test and use the system.

The picture on the left shows the satellite antenna installation on top of one of the coaches. It looks a bit odd on the otherwise very streamlined train but the round shape probably keeps the additional drag to a minimum. Nevertheless, I'd be interested in finding out how much extra energy is necessary to  push the train beyond 300 km/h due to that.

At 7 a.m. in the morning, throughput in both uplink and downlink between Paris and Brussels was tremendous. Speedtest.net reported downlink speeds of more than 10 MBit/s and more than 3 MBit/s in uplink direction! While the link dropped a number of times on the trip to Brussels it was only for a few seconds each so that was probably only apparent to an attentive observer like me running a data trickle in the background to detect just such occurrences. However, the outages were short enough that it didn't affect streaming applications once enough data was buffered. Watching a Youtube video, full screen and in HD quality worked just fine.

As all data is transferred via a satellite in a geostationary orbit, round trip delay times were in the region of 650 ms. While voice calls and even Skype video calls work well over the system the delay can be felt in the conversation. Loading a graphics intensive web page works quite well and fast but it feels a bit sluggish for a moment after clicking on a link or entering a web address before the download of the page starts. This is again due to the very high round trip delay time compared to other systems such as ADSL with a round trip delay time of 50 ms, or the 120 ms over a 3G connection. Having said all that, the experience is still great, especially taking into account that the countryside is passing by at 300+ km/h when looking out of the window while that HD video is streamed over the satellite.

The satellite connection has one real several imitation: In Europe, the geostationary satellite hangs close to the horizon, so it is not always possible during the trip to keep the connection. In such cases a ground based backup is used. In the Brussels main station, for example, Wi-Fi is (probably) used. Downlink speeds came close to 16 MBit/s and round trip delay times were lower than 50 ms. The tunnels around Brussels were covered as well, although I was not sure exactly what technology was used. In other places, especially in the hilly terrain between Belgium and Germany, the satellite connection doesn't work too well either, probably because the train winds its way through narrow valleys and many tunnels. GPRS and UMTS network in that region seem to be patchy at best so the experience on that part of the track wasn't too great.

In between I should also mention that I didn't find any services that were blocked. VoIP worked well, IM worked well and my IPSec based VPN also worked fine over the system.

In the evening I made the same trip in the other direction. It seems a lot more people were using the system in the evening as speeds were much slower than in the early morning. While I could still reach fantastic transmission peaks of 3 MBit/s in downlink and more than 1 MBit/s in uplink, I experienced continuous high packet loss and frequent connection outages in the range of minutes even on the flat terrain between Brussels and Paris. The bad weather and heavy rain might also have had something to do with it, it's difficult to tell from a single ride.

Summary:

Of course I had my expectations before trying the system. In most cases I found it to be much faster than I expected. Especially the main applications such as web browsing, e-mail and VPN tunneling to the company network worked fine. The system has its limitations in hilly areas and cities when there is no direct line of sight to the satellite. While the system automatically switches to GPRS or UMTS in such cases, it didn't work particularly well in many of those places areas, as they were probably not covered very well. It can work much better over 3G as I have experienced here. Overall, however, I was very impressed with the system and I think it's a great service!

…I was asked today. A clear opinion here: Yes and no.

Yes: When I reviewed some of the future chipsets for my recent book it was clear we are moving to processor speeds beyond 600 Mhz, built in camera hardware units of those chipsets supported resolutions of 10-12 megapixels and a touch panel interface was also part of the unit.

No: Such specs tell you nothing about the form factor of a future device. Examples: Just knowing that there is a touch interface tells you nothing of how usable the interface will be. A chip spec doesn't tell you the physical characteristics of the device, e.g. like will it have a hardware QWERTZ keypad, etc. Also, there are usually supporting chips around the chipset like GPS, motion sensors, compass, etc. How they are mixed and matched is not on the datasheet either.

One interesting domain I haven't yet too much looked into is the specs for the radio front end chips. This info would be very interesting to get an insight which technologies (GSM, UMTS, LTE, CDMA) can be supported in future devices, and, equally important, which frequency bands can be handled with a single front end chip. If you have some good references here, please consider leaving a comment.

A non-technical blog entry today addressing the question many have asked me before: Why am I running this blog?

Obviously, I like to write and I like to share stuff I have learnt or that I think about with other people. My thinking and learning, however, is not self contained, i.e. I don't just sit down in seclusion and wait for that light bulb over my head to light up. I am inspired by things I see, read and experience.

It's great, for example, to have full access to 3GPP standards, to the meeting reports, to the change requests, in short, to everything that goes on in standardization. If there's a doubt, these documents clear things up.

It's also the blogs out there on wireless topics that keep me thinking. By reading them, I challenge my thinking and end up with lots of "yes, and" or "yes, but" or "yes and what if" questions which lead to new insights, ideas, and often to new questions.

It's the people I meet at conferences such as ForumOxford, the Mobile World Congress, Mobile Mondays and others which equally challenge my thinking and give me new ideas, direct or indirect.

And last but not least, it's the books on mobile topics and which I sometimes review on this blog. All together, it's my personal open innovation.

So by writing this blog, I do not only have to clearly think things through before and while I write them down, but it's also about giving something back to the community from which I profit. So, thanks very much for reading this blog and especilly for your comments, both agreeing and disagreeing, they are a vital part of the process as well!

Verizon recently announced Gemalto and G&D as their partner for SIM cards and remote provisioning for their LTE rollout. Remote provisioning of SIM cards (e.g. change the list of preferred network operators, network name, etc.) has become pretty much common over the past couple of years but there might be a twist with Verizon and LTE:

Today, remote provisioning of SIM cards is done via SMS. When such special SMS messages are received by the mobile device it automatically forwards them to the SIM card for execution without interaction with the user. What I am not quite sure is how that will work over LTE, because SMS over LTE is not standardized. Of course it would be possible to use the "3GPP CS fallback" feature to 2G GSM or 3G UMTS to receive the SMS messages. However, in Verizon's case that might not be possible for two reasons:

• Their legacy system is based on CDMA, which does not have SIM cards. Hence, the CDMA part of a mobile phone might not have the necessary standardized software to forward those data SMSes to the SIM card.

• The current LTE specs of Verizon say nothing that LTE terminals have to have a CDMA part.

So I am not quite sure how over the air provisioning will work in practice in Verizon's case!? Has there been something standardized in LTE or CDMA for "native" remote provisioning of SIM cards? If you have more info, I'd be happy to hear from you!

In today's 3G networks, voice calls are often in the so called “soft handover state”, which means that the radio network controller sends and receives the data for a voice call to and from several base stations simultaneously. The mobile then receives the voice call data stream from all three cells simultaneously and combines the received signals. While this wastes some bandwidth on the backhaul, these soft handovers often help to reach mobiles at the cell edge, which receive one or more cells with a similar strength.

For HSPA data transmissions, however, the soft handover is not used as the base stations autonomously decide when to schedule data on the air interface and thus, it is pretty difficult to synchronize the transmission over the air interface of several cells. In LTE, such a direct cooperation between cells is also not foreseen for the moment, even though there might be some benefits for mobiles at the cell edge. For LTE Advanced, however, people seem to have started thinking about it again. Instead of sending the same data stream over two or more cells, however, they are thinking about a cooperative MIMO scheme, i.e. each base station sends a different data stream and the mobile then analyses each data stream separately. The result would be a higher throughput for that mobile.

As Moray Rumney points out in his recent book, though, such a cooperative MIMO scheme would be quite challenging to implement in the network. First, it would put quite a demand on backhaul capacity and second, data would have to be exchanged between the base station with a delay of a millisecond or less. O.k., it is still some years away and technology advances, but I tend to agree with him, that's quite challenging to do. What do you think?

Lately I get the impression fewer people use clamshell phones than in the past. Even in the US it seems to me that when I was last there I saw more people with Blackberries running around and happily typing away on the keyboard than people still using a clamshell phone. So why? Could it be that the clamshell format is great for voice calls, i.e. quite sexy to open it up, but does not lend itself very well to text or web based applications? The smaller screen of the clamshell vs. sliders and the act of opening up the phone to check for messages, send a quick sms, e-mail or surf the web might just be that tiny little bit too much these days!? What do you think, what are your observations?

Recently, I had an email conversation with a reader and he sent me a list of mobile phones he had in the past. Interesting memories coming up. I doubt my list is equally long but I think it is time to make my own so I won't forget. Here we go:

• I started with a Bosch 738 (I am German, the French will get the irony)
• A Siemens S25 (my first color phone)
• A Ericsson T39 (my first GPRS phone (!), could only do static assignment, only worked in one network)
• A Siemens S45i (GPRS worked well after a couple of software upgrades)
• A Siemens S55 (browser, color screen, a couple of hundred KB of flash memory with file system!)
• A Sony-Ericsson V800 (my first UMTS phone)
• A Nokia 6630 (only used as a modem at the time)
• A Nokia 6680 (First phone on which I discovered the power of S60)
  
• A Nokia N70 (Natural evolution from the 6680)
• A Nokia N93 (Bought because of the camera and the twist) 
• A Motorola V3xx (initially used as an HSPA modem, today also as backup phone)
• A Nokia N800 Internet tablet (o.k. not quite a mobile phone)
• A Nokia N95 (my main phone today in 2009, bought because, well, because of everything 🙂
• A Nokia N82
• A Nokia 5000 (low end with color screen, used as phone and to test apps on an entry level platform)

And in addition:

• I had a Palm 3, and two HP PDA's, discontinued to use them when I bought the N70, as I could do all the calendar stuff, etc. on the mobile phone
• A Sierra Wireless 850 1.8 MBit/s cat 12 HSDPA PC-card modem
• 2x Huawei E220 3G USB dongles (3.6 MBit/s cat 6 HSDPA) for Internet access. In use today. They might be a bit clunky by today's standards, but they just work in all networks I have used so far, which can't be said of other 3G sticks I tried.

There we go, the list is already longer than I thought 🙂

Over the past days there have been reports in the press that Vodafone Germany will trial LTE in the 800 MHz digital dividend band to collect experience how this frequency band can be used for rural broadband Internet coverage. The reports also mentioned that a TV station (the WDR) will also take part in the trial. A TV station?

Why, I wondered at first, as all but Unstrung did not go into the details of why a TV station is part of the trial. So, according to Unstrung, the TV station is part of the trial as they are interested, or a bit worried, that using spectrum in the 800 MHz band for broadband Internet could have an impact on their TV broadcasts in an adjacent band. Further, wireless microphones are using the digital dividend band today and it seems it is not quite clear of what can be done about that in the future (see here and here).

So the outcome of this part of the trial will be quite important to figure out if or how all of the 72 MHz foreseen to be assigned in the 800 MHz band for mobile broadband systems can be used without generating too much interference for TV broadcasts. An interesting topic to follow.

And another follow up post on the University of Oxford's Future Technology Conference: During on of the many "socializing breaks" I met Eric Seuret of 3SMobile and he told me about the crop insurance via SMS application for farmers in Kenya he has developed for Syngenta, a large global agriculture company. The concept is so elegant, simple and has the potential to improve the lives of many people, so I asked Eric to send me some more details about how the service works. Here are the details:

The weather insurance solution via SMS helps protect small holder farmers against the risk of drought.  When a farmer purchases certain Syngenta seeds and crop protection products he obtains special insurance stickers.  When he has collected a certain number of stickers he gets an ID number which entitles him to 1 acre of free weather insurance for that season. To obtain the insurance he does not need to fill out any forms or contracts.  All he needs need to do is SMS a unique insurance code ID to a local number. The system then verifies that the insurance code is valid and confirms the farmer's insurance status.  If the farmer has a larger plot of land he can obtain multiple cards and insurance policies.

Throughout the course of the year the farmer is kept informed of major weather issues that are related to the policy via SMS.  At the end of the season the historical weather data is used to determine which farmers are entitled to a payout based on their region.  In the case of a payout the farmer is notified via SMS and they can go to the stockist to obtain the payout.

It is the first time that insurance has been made available to small holder farmers in Kenya with 1 acre or less of land.  This has only been possible through the use of mobile technologies were the solution finally became cost effective.  Mobile phones were used to simplify the administration, reduce costs, enable immediate registrations, and to help form a direct link to the end customer. In many cases the mobile phone represent the only way to reach the farmers without physically visiting the remote villages.  The innovative solution is currently running as a pilot project and is so far proving to be very successful.

The insurance concept and solution was designed by Rose Goslinga and Fritz Brugger for the Syngenta Foundation for Sustainable Development and developed by Eric Seuret.

If you've been waiting after my report on the ForumOxford Future Technologies Conference 2009 for the presentations of the other speakers, they are now online and can be found here. A little bit hidden but definitely worth a look is Jonathan Marks' video summary of the event. Not much more to say, so head over and enjoy!