 The magazine of the Melbourne PC User Group Wireless Alphabet Soup Ash Nallawalla ash@melbpc.org.au |
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| If you have been reading the technology press lately, you will know that acronyms such as 3G, GPRS and Bluetooth are appearing with increasing frequency. I enjoy keeping up with technology, so I will try and paint the wireless landscape as I see it. There are numerous Web sites (listed at right) that offer technical details, so I will try to keep this article short and simple. |
www.3gnewsroom.com www.umts-forum.org www.wap.com www.the3gportal.com www.palowireless.com www.nttdocomo.com www.gsmworld.com www.mobileapplicationsinitiative.com |
We are approaching the third generation of mobile phones and wireless devices, hence the appelation 3G. 1G was the analogue system, 2G is the current GSM, CDMA and TDMA (in the US) system. 2.5G is the recently released GPRS (more on that later). 3G includes a handful of 3- and 4-letter contractions, but they are already talking about 4G! Yes, you will still be able to speak over these new media, albeit more efficiently, but the main difference will be noticed in the non-voice modes of communication.
2G
We can leave the old 1G brick-like, analogue relics in the museum, as most of us who have mobile phones use GSM (Global System for Mobiles), while some use CDMA (Code Division Multiple Access). A few Americans use GSM, but on a higher frequency band, but the majority use TDMA (Time Division Multiple Access).
WAP Is Not Crap
The Wireless Access Protocol or WAP is now featured on several phones. Its role is to provide Internet access to mobile phones. My Motorola LSeries+ phone has WAP. Unfortunately, some critics coined the slogan "WAP is Crap", because it did not live up to their expectations. One cannot create an attractive Web page in a tiny phone window with three or four lines of black-and-white text and graphics that cannot use shading.
I agree that the average handset is hopelessly inadequate for typing text, but there are a few applications that are easy to use as well as useful in themselves. They tend to be ones meant to be used by trained staff rather than the general public. There is also a problem with specific handsets, not the technology. For example, my phone will not let me store a bookmark through Telstra's WAP gateway, even though the instruction manual shows me options that I cannot call up. It was a pain to key in long URLs. My colleague's Nokia 7110 had no trouble with storing bookmarks, but could not run the applications that my phone could.
From time to time we read about some new application for WAP, such as the "World First" Coca Cola machine in a Sydney railway station that dispenses cans if you dial it from a WAP phone. A former President of the Canberra PC Users Group, Karl Auer, who now lives in Bruettisellen, Switzerland wrote to say that their bottling plant has had two such machines in operation for over a year, although he has not seen anyone using a phone to make a purchase.
WAP applications are written using Wireless Markup Language (WML), which is similar in concept to HTML and coexist with HTML Web servers. Their pages have a .wml suffix and cannot be called up with a Web browser. You can, of course view .wml pages with a WAP phone, but it is cheaper if you install a WML browser on your PC and access the same pages over the Internet. That's right; your phone company's WAP gateway is connected to the Internet and not merely a handful of WAP sites.
If you wish to download a WML browser, go to http://www.apachesoftware.com and try their free WML browser. http://www.wap.com is as good a site as any to find other WAP/WML resources, including tutorials on coding WML pages.
Regardless of the wireless technology, data access will need a good user interface to be popular. In North America, my former employer issued all sales staff with two-way devices known as the Blackberry, made by Research In Motion (RIM). We had trialled the Palm VII, which has a built-in, flip-out antenna, but the Blackberry won because it has a tiny keyboard. It enabled us to read and answer e-mail from most built-up areas, even though the replies were brief. We could later respond properly with our laptops. The Palm VII and the Blackberry do not use WAP, but other "always on" technologies, which is a suitable entree for 3G.
Always On Is Not Always On
You may know that today's phones include models that act as data modems and many people use their laptops or palmtop devices to connect to a modem at the other end, usually an ISP or their office. This connection is known as circuit-switched, namely, your connection is not shared with anyone. While that sounds like an "always on" situation, it is not. When you disconnect, neither you nor the other party or service can connect with each other and, say, exchange an e-mail (and its acknowledgment).
3G Is Always On
We are spoilt by our untimed landline phone calls, so timed voice or data calls have had a harder time to be accepted compared to, say, the UK. I don't surf the WAP world with my phone because the meter is ticking away while I painfully key in a URL or am thinking before clicking a button. Most of my WAP calls cost me less than a dollar each, but I know that I was paying for dead time. This will soon be history, I hope.
GPRS
GPRS (General Packet Radio Service) is also known as 2.5G, as it is a step towards 3G and was recently introduced here. I first encountered packet-switched radio about 15 years ago in amateur radio and I must confess that I could not see its relevance then. Packet radio is conceptually similar to Ethernet in that data is sent in small packets interspersed with other users' data. Many users can share a common frequency, hence the service can be offered at a lower cost to us. We only pay for the data, not the time the device was switched on. Yes, I can see GPRS being more user friendly, provided that the user interface is equally friendly.
GPRS uses the existing phone bands and has a maximum data throughput of 115 kbit/s, although 50 kbit/s is nearer the mark in practice. By 2003, a technology known variously as Enhanced Data rates for Global Evolution or Enhanced Digital GSM Environment (EDGE) will offer in the USA rates ranging from 100 through 384 kbit/s. One target market for GPRS is the travelling professional who needs to connect to the office through a Virtual Private Network (VPN). In Australia, owing to our untimed phone calls, I would take my chances from a hotel room with a landline analogue modem than a 50 kbit/s GPRS VPN link. On the other hand, for an extended session away from a landline, GPRS begins to look very attractive.
i-Mode
i-Mode is also a packet-switched technology that is very popular in Japan (over 23 million users) but will soon be seen in North America. It uses a simplified form of HTML called Compact Wireless Markup Language (CWML) and not WML. It supports colour and video.
WCDMA
Wideband CDMA (WCDMA) will be launched on 30 May by Japan's major carrier NTT DoCoMo. Dubbed Freedom Of Mobile multimedia Access (FOMA), it has a maximum downlink transmission speed of 384 kbit/s. FOMA will provide much clearer voice quality, and fast, smooth video images and other data. Other services will include video phone, multi-access, i-Mode and M-stage visual image distribution service. In the near future, other services will be added, including M-stage music distribution service and i-Motion, which allows users to enjoy video clips through i-Mode.
WCDMA uses spread-spectrum transmissions, which use a wide chunk of the frequency spectrum by hopping across it in a pseudo-random pattern or in a direct sequence. It is quite immune from amateur eavesdropping and from interference.
Bluetooth
Ericsson has developed a cable-replacement technology known as Bluetooth, which enables both non-voice and voice devices to communicate with nearby devices. A practical, early application is Ericsson's Bluetooth Headset. The hands-free device for my phone is a wired earpiece with a boom mike. As I don't like to have it on my ear all the time, I sometimes find myself trying to plug it into the phone and onto my ear while driving, which is dangerous. With a Bluetooth earpiece and mike, there would be no fumbling or tangled wires.
You can create a small network known as a Piconet with up to 255 Bluetooth slaves and one master, although only seven slaves can be active at one time. One Piconet can talk to another and thus form a Scatternet. Slaves can be shared with other Piconets. You can see how data can be passed from one device to another.
Bluetooth operates in the 2 GHz band (as do other 3G technologies), which is deeper into the microwave region compared with today's 900/1800 MHz GSM bands, so you can expect to see more controversy about the possible hazard to one's health. Nevertheless, I expect to see many interesting uses for this technology, for example, all electronic devices in our homes could talk to one another. It's more fun trying to imagine what could possibly go wrong in such a scenario!
WiFi
Bluetooth faces competition in some quarters from IEEE 802.11b wireless LANs, also known as WiFi, mainly because this 11 Mbit/s technology is already popular and is faster than the 2 Mbit/s offered by WCDMA and cdma2000. A few home users (notably Mac users) use it because they don't need to cable their homes as they would for conventional Ethernet.
UMTS
Universal Mobile Telecommunications System (UMTS) is one of the major new 3G mobile communications systems being developed within the framework defined by the International Telecommunications Union (ITU) and known as IMT-2000. Once UMTS is fully implemented, computer and phone users will have Internet access as they travel and have the same set of capabilities no matter where they go.
Conclusion
I have only skimmed the surface of several new technologies but the links provided will lead you to much more information. Let us hope that the user interface and the cost of using 3G technologies will prove to be popular.
Reprinted from the June 2001 issue of PC Update, the magazine of Melbourne PC User Group, Australia
