Wireless Computing

Say Goodbye to Golf Games at the 'Customer Site'

Francis Vale


Something New in the Air

Ubiquitous, wireless, mobile computing probably means the death of the PC as we now know it. If the point of the PC is to enhance user productivity, then wireless computing is way ahead.

Fact: studies have shown that four out of five phone calls fail to get through, because she or he is away from the phone, or busy. Fact: studies have also shown that more than 20% of an employee's time is spent away from his or her desk.

These two facts produce a likely third: groupware messaging systems, like Notes and Exchange are focused on solving the wrong set of problems. The real issue is how to keep scattered employees in touch with the people they need to stay in touch with, and do so with minimal disruptions. The issue is thus communications, not messages. Solve the problems of the medium, and the messages will naturally follow. The medium is truly the message.

Wireless mobile computing and communications is becoming a marketing bonanza, with hundreds of wild eyed vendor pioneers hell bent on getting to the consumer mother load. The trail west began in 1992, when a watershed event in world telecommunications took place. In 1992, the number of new subscribers to fixed (land-based) telecommunications stopped growing. No new growth was registered. In more than ten years, this had never happened. But, also in 1992, 15% more new subscribers showed up on the planet's telecommunications rosters than in 1991.

How is this? The answer to this anomaly is that all the new growth was occurring in wireless telephony, and in particular, cellular radio networks. 1992 thus marked a turning point, and it is likely that the telecommunications industry will never look back. At the present time, global market penetration of wireless phones is less than 10%. (The one exception is Sweden, which has already exceeded that magic figure.) Once global penetration for wireless exceeds the 10% threshold, then the marketing dam will have indeed been broken.

But how to stay in wireless touch? There are currently several options competing for your mobile access money: 1) pocket pagers, 2) wireless phones, 3) wireless-enabled personal computers, and 4) wireless-enabled personal digital assistants. The likely winner in this mix is a successful marriage of the wireless phone with a PDA. But it will no longer be a phone, nor will it be a PDA. It will be a sui generis device. Most important from a computing perspective, this new device will probably use digital signal processing chips (DSPs) as its primary compute brain, with a traditional CPU (e.g., a Pentium or P6) playing a secondary role.

Finally, computers as we now know them will become invisible in our everyday workflow, as well as in our personal lives. They will, so to speak, just disappear into the woodwork. This role reversal has enormous implications for the computer/communications industry, most especially for Intel and Microsoft. But before we launch ourselves into the wild blue ether, let's do a quick survey of the mobile access/computing industry, and your current wireless options.


These ubiquitous, cheap to use devices are undergoing a transformation. No longer mute, passive receivers, they are becoming intelligent communicators. Motorola's new PeopleFinder (1-800-818-7483) paging transmitter system is a good example of this new breed. The PeopleFinder hooks up to a computer's serial port, and replaces the modem. The PeopleFinder can transmit a message to a remote pager in around six seconds, as compared to the lengthy wait (a minute or more) typically required by outside paging service providers. Moreover, Motorola offers its SiteCall software to go along with the PeopleFinder. Sitecall is a set of software utilities designed to help you integrate your existing computer applications with the PeopleFinder. Numerous features set PeopleFinder apart from regular paging systems.

For example, PeopleFinder can notify you that a phone call is waiting. If you are way from your desk, it will direct you how to pick it up at another extension. And if you don't pick up within a specified time, the caller is put into your voice mail. Other companies are also developing PeopleFinder software packages. Some, like ABS-TALKX (Westbury, NY, 516-333-7900), directs the paged person to an extension to pick up the phone call, even before the call is actually transferred. This feature cuts down caller waiting time. The primary limitation of PeopleFinder is its five mile or so range (depending upon the surrounding environment). PeopleFinder does provide for the use of repeater-style units and additional power amplifiers, so this range can be extended. But a second pager service will be needed if you want to roam beyond the allowed PeopleFinder range.

Looking down the road, it would be but a small step to equip PeopleFinder pagers with an infrared-based, network transmitter/locator device (like Executone's Locator System with its IR badge -- Milford, CT, 203-876-7600) that kept a PBX system informed of where you were in the building. Call transfer then becomes much more automatic. Beyond that, if a small telephone were built into the PeopleFinder pager, then you might have a true 'Beam me up, Scotty' personal communicator.

Other paging companies, like PageNet, think it's much nicer to hear your master's voice. So PageNet is implementing a national network that digitizes the incoming message, does a store and forward via your mailbox, then locates you no matter where you are. Once found, the message is audibly played back to you over a small speaker built into the PageNet pager. The message is also stored in the pager, so it can be played back later on.

PageNet also avoids using the typical overkill of nationally broadcasting all pages. Instead, similar to cellular phones, the distributed PageNet transmission towers keep tabs on where you are via a signal regularly emitted from your pager. Thus, your messages are directed to the tower nearest you, instead of using promiscuous broadcasting.

Alphanumeric pagers with two way messaging and notification features are also now becoming commonplace. Mtel's SkyTel paging system, which offers guaranteed delivery across the nation, exemplifies this growing technical trend. You can respond to messages directly from your SkyTel pager. SkyTel (408-451-3990) uses Motorola's ReFLEX 25 and ReFLEX 50 two way response system. ReFLEX provides much more effective use of the restricted paging bandwidth, with the result being much higher messaging throughput. This spectrum shoehorning by ReFLEX provides SkyTel's limited message acknowledgment capabilities, including notification of delivery. Motorola is also shipping ReFLEX software development kits to ISVs, which should add many new capabilities to the two way paging arsenal.

But some static has crept into SkyTel's marketing plans. Users are complaining of limited coverage, and delays in getting messages. Moreover, the SkyTel transmissions have trouble getting through to the inside of many buildings. The SkyTel infrastructure is still very much a work in progress, and it will probably not be until the end of 1996 before the system can effectively compete with one way paging services.

Monthly costs for two way paging systems are expected to be about 50% more than one way systems. But they should still end up being cheaper than using other wireless data delivery systems, like cellular's CDPD. In addition to SkyTel, during 1996, a slew of other companies will have thrown their hats in to the two way paging wireless ring.

Radio Babel-on

Among the new contenders are Paging Network, PageMart, Mobilcomm, AirTouch, and AT&T Wireless Services. In 1996, it is expected that a half million subscribers will be beeped with two way messages. But how they will communicate with one another is a different story. The various vendors' paging systems are incompatible. Some services randomly mix the chronological order of messages, support different packet sizes, and use seven or eight bit data transmission. A SkyTel two way pager won't work on a PageNet network, for example. And AT&T, typically, is doing its own two way protocol thing, which is also completely incompatible with Motorola's.

This radio tower of Babel will not be going away any time soon. The Personal Communication's Industry Association (PCIA) has finalized a spec called TDP, (Telelocator Data Protocol). This new standard will allow spreadsheet, WP, and other data to get shoehorned into a pager. But as usual, not everyone agrees, and some paging service vendors think that TDP is resource hungry, and will require too much modification to make it fly. So, these disaffected vendors have embarked on implementing McCaw Cellular's LSM (Limited Size Messaging) protocol. McCaw 'donated' LSM to the Cellular Digital Packet Data Forum. Motorola supports TDP, while rival AT&T Wireless Services plans to use PACT (Personal Airlink Communications Technology), which incorporates LSM.

E(ther) Mail

Although two way paging is limited to small message sizes (which may be why the industry has so many acronyms), it can also receive your e mail, as well as initiate it. Of all the national data radio messaging systems that support e mail, two of them, RAM Mobile Data and ARDIS, are probably the most well known.

RAM (800-726-3210) uses the packet switched Mobitex Digital Wireless Network, developed in Sweden in the 1980's by Ericsson. RAM uses equipment from either Ericsson GE or Motorola. In addition to the usual store and forward features, RAM offers software to build interactive, packet-stuffed messages for use in other applications. There are no 'long distance' charges for RAM users. The cost per packet is the same whether it is sent across the country or across the street. A number of ISVs also offer products that support e mail integration with RAM (as well with ARDIS). Some of these packages also permit LAN-based e mail products to seamlessly integrate, at 4,800 baud, with roaming user systems in the field.

ARDIS (800-662-5328), which is owned by Motorola (and up until recently, also by IBM), features coverage across most of the country, but hilly terrain can be its range-limiting nemesis. If you are out of the ARDIS packet-switched range, you are also out of luck, as no provision is made for tying into other vendors services. ARDIS features message store and forward, as well as provides message acknowledgment services. ARDIS also offers a link into America On Line. A remote ARDIS user can thus utilize any of AOL's services, including the Internet and e mail. ARDIS is upgrading to 19.2 Kbs speeds, but in some parts of the country, it's still only 4,800 bps. Lastly, ARDIS offers RadioMail, a wireless e mail service with national coverage. Note: it is the sender who is charged in RadioMail. The receiver gets a free e mail ride.

With both RAM and ARDIS, you will need a wireless modem, which range in cost from a few hundred dollars to about $1,000. Small wireless PCMCIA cards are also now on the scene, shoving the older, heavier modems off the retailers shelf. ARDIS also has its own mobile terminal offerings, based on PDAs. One is the Marco, which utilizes the Apple Newton. The other ARDIS PDA is the Envoy, which employs General Magic's Magic Cap. About 2,000 Marco and Envoy units are now out in the field. Given that their backers expected to sell tens of thousands of these units by the end of 1995, Marco and Envoy are an obvious disappointment.

Furthermore, both RAM and ARDIS may be in for some stiff competition from the new two way paging systems. In comparison to the 100,000 or so combined RAM/ARDIS users, 500,000 subscribers are expected to be using the new two way pagers services in 1996.

Car 54, Where Are You?

Of course, the best possible paging/messaging system would not only ensure guaranteed delivery, it would also let the interested party know your true whereabouts, anywhere on the planet. One company already offers such a messaging service. It is Nmarsat. This service combines messaging with global positioning satellites (GPS). This system is a natural for keeping track of your trucks and ships. Within seconds, Nmarsat can locate a vehicle down to within a few yards, as well as indicate which way and how fast the vehicle is moving. This system requires an 18" or so diameter antenna to be mounted to the vehicle. And the antenna needs unobstructed blue sky to do its thing.

However, the imminent availability of low cost, PCMCIA-based GPS cards, coupled into PCS or cellular phones, means that heavy duty equipment requirements like Nmarsat's (which cost about $10,000 per equipped vehicle) will quickly become a thing of the past. Pretty soon, your boss will know exactly where you are, at all times, and which way you are headed. So get ready to say adios to those golf games at the 'customer site.'

Wireless Wide Area Telephony

Without question, this is where most of the hot mobile action is. Although radio cellular-based telephony had its birthplace in America at Bell Labs in the 1970's, it was, in fact, the Europeans who initially picked up the cellular ball and ran with it. The Nordic countries (Sweden, in particular) were actually the first to introduce commercial cellular service in Europe, with the advent of the Nordic Mobile Telephone (NMT) system in 1981. In 1983, the U.S. began playing cellular catch-up to Europe, with the introduction of Advanced Mobile Phone Service (AMPS) over the 800 MHz frequency band. AMPS is now widely used in Latin America, as well as in Asia, and the CIS.

Analog cellular telephones (which are really two-way radios) have been a tremendous hit in the consumer mobile communications market. Today, nearly as many people U.S. use cellular phones as use pagers (19 million callers vs. 22 million using pagers). This user growth is expected to accelerate. In fact, many studies indicate that the majority of all telephone growth will be in wireless systems, as opposed to fixed landline.

But these ever increasing millions of cellular users are posing big operational problems for U.S. operators. A victim of their own success, U.S. cellular companies are running headlong into capacity, as well as operational, problems. Digital-based cellular is now seen as the industry solution, and two digital standards for multiple call sharing over limited cellular bandwidth are now fighting for market dominance. One is TDMA, the other is CDMA, both of which will be discussed at length in the next issue of 21st.

We will also see how the Federal Government blew a great opportunity to shape the wireless future.

Copyright 1996, Francis Vale All Rights Reserved

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