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Just recently I was, and actually I quite am, quite extatic about having reached 11 MBit/s throughput in a live 3G network over here in Germany. But the specs are already two orders of magnitude ahead.

In a recent 3GPP RAN meeting, a new set of LTE-Advanced UE categories have been specified. The highest one, Category 8, specifies a transfer mode for 1200 MBit/s downlink and 600 MBit/s uplink transmissions. That is, of course, if we'll ever see devices with 8 receiver antennas and networks that have base stations with 8 transmit antennas per sector. Also, a channel bandwdith of 40 MHz is required. Each parameter on its own is already quite a stretch when compared to the current state of the art. But then, only ten years ago, we were creeping along with wireless speeds of just a couple of kilobits per second. Two orders of magnitude less, actually.

For those who want to have a closer here's a link to the 3GPP RAN WG1#62 report. In the report, search for R1-104944.

While I'm personally a bit sad that non of the new Symbian^3 based phones Nokia presented at Nokia World recently is a vertical slider with a traditional T9 keypad there's one thing that makes my international roaming heart jump: All devices presented, namely the C6, C7, E7 and N8 all come with a pentaband 3G receiver included. In other words, while my current single band UMTS device has to fall back to GSM when roaming for example in the US or Canada, these devices should work pretty much everywhere you go. Also good for Nokia as that significantly reduces the number of device variants. For details here are the product pages for the N8 and E7.

In some countries in Europe such as Germany, for example, there are quite a number of offers for daily 3G Internet access now in the range between €2.50 to €5.00. Especially €2.50 offers sound quite cheap, almost like network operators giving their services away for free. But how much is that compared to the daily fee of a DSL line at home? Let's compare with a DSL line that costs €30 per month. That would be €1.00 a day. In other words, there's still a premium for wireless in the daily charge. So while it sounds cheap, summing up €2.50 over 30 days brings you to €75. That's quite a sum so it quickly pays to go for a monthly option if mobile Internet access is required for more than just a few days per month.

Every now and then I see in computer magazines or tech websites some network speed measurements (including my blog). Often, however, they are based on single measurement experience or maybe based on using a notebook in a few areas in the network. While this might be good for telling the performance in those places it doesn't really capture the overall capabilities of the networks. For this, so called drive tests are required and for comparisons between different networks, measurements must be performed in the different networks simultaneously. That's quite a challenge but the resulting data is well worth it. Here's a link to a recent article in a the German computer magazine "Chip" that has made an extensive test of the German networks. Google can help to translate the pages for those non-German speakers of you. Highly recommended for the background information and the interesting pictures of the measurement equipment and the results. If you know of similar tests having been published in other countries, please let me know!

It's good to see that the number of prepaid SIM offers in many countries that can be used for 3G Internet access keeps going up and the Prepaid Wireless Internet Wiki keeps growing and information is constantly updated. Also, I keep noticing that prices are getting more competitive. For my two weeks of vacation in Italy this summer, for example, I used a SIM card from mobile operator WIND which I already used during previous trips and noticed that prices have further gone done. For my two week stay, the 1GB / month data option was quite sufficient which now only costs 9 Euros + a 4 Euro activation charge. For longer stays the 10 GB / month option for 20 euros might also be an alternative. Compare that to what some hotels charge for Wi-Fi per day…

Hm, have a look at the design of the 3-year old Nokia N82 on the picture on the left. Those rounded edges and metallic look are quite similar to the general exterior design of a recent popular product!? Except, of course, that the frame is not used as an antenna. Suddenly, the phone is twice as beautiful as before…

Ever since I first visited the Fraunhofer FOKUS institute almost exactly two years ago, I've remained in contact with the researchers there as they are working on interesting research projects in the wireless core network and IMS domain. Next month, on the 14th and 15th of October, they are hosting a follow up to their IMS conferences in the previous years called "Future Seamless Communication" or FUSECO for short. They've got a long list of interesting topics and speakers for their conference both from the industry and academia, something I always enjoy as both sides can learn a lot from each other. If you are interested in wireless core network topics it's definitely a conference not to be missed. Here's the link for a closer look. Enjoy!

On of the shortcomings of current 3G networks compared to fixed line Internet connections is that to save power and network resources, most networks today put the connection into Idle state from which it takes considerable time (around 2.5-3 seconds) to come back into a fully active state. A solution for this is the Cell-PCH state from which the mobile can return into a more active state in less than a second. However, this state is not activated in many networks yet. For details on the topic see here, here and here. Lately, I have discovered that there are a number of live networks who have begun using Cell-PCH.

The latest example is Vodafone in Italy in some areas (e.g. in Rome, but not in Naples). While the other three networks in the country put the connection in Idle state after around 5-6 seconds in DCH state and around 30 seconds in Cell-FACH state, the Vodafone network puts the packet connection to my mobile into Cell-PCH state after having been in the fully active state for 5-6 seconds and 5-6 seconds in the Cell-FACH state afterwards. As my N95 does not support fast dormancy, I much prefer this behavior as my battery noticeably lasts longer and reaction times after reading a web page on the device for more than 30 seconds is much faster.

Back in 2006, UMTS was still a more or less new kid on the block and during my travels I often experienced interoperability issues with devices working well in their home network but not so well in other networks when traveling abroad. Here's an example. Things have considerably improved since then but still every now and then things go wrong. Here are some recent observations from Italy:

• My now already somewhat old N95 just won't stay in the WIND network in manual selection mode. At some point it looses the network and miraculously reappears on the TIM network. I've never seen before that the device would just go to another network while in manual network selection mode. Definitely a first.

• My default 7.2 Mbit/s 3G USB stick, which I would consider very stable in my German home network, every now and then completely looses the connection to the WIND network in Italy despite good network coverage and no movement and goes into network search mode. Quite incredible. Also it sometimes completely hangs and doesn't react anymore. Only a power cycle brings it back to live.

• It seems the stick quite frequently has a problem to go from Idle to Cell-DCH state. In such cases, the stick tries for about 30 seconds to change the state before it succeeds and data flows again. Totally unacceptable. The only thing that helps is a constant ping which keeps the connection at least in Cell-FACH state.

Luckily I still have my somewhat old Huawei E-220 with me. Despite being a bit bulky and only HSDPA 3.6 Mbit/s capable (no HSUPA), this is the most stable piece of 3G hardware I ever had and it displays non of the issues described above.

This year for the first time, data roaming prices in Europe are for the first time low enough for my mobile device Internet use, which is mostly Opera Mini and e-mail. With a still high price of around 2 Euros per megabyte, I wouldn't dare using it with a computer but for mobile browsing using compression and fine-tuned e-mail settings I use about 1 to 2 MB a day. That saves me the pain of carrying two devices simultaneously. Obviously for the notebook, I still prefer a local SIM card with a data option. But from a consumer point of view we are on a good way. I wonder how long it will take before I will dare using my home SIM card with a notebook, too!?