Dan Bricklin's Web Site: www.bricklin.com
Signals and the Ubiquity of New Carriers
A way to look at which companies advancing technology will affect and how.
I was visiting New York City this past summer as part of a vacation. I was leaving the hotel to take a long walk in lower Manhattan. When I asked the person behind the desk at the hotel for directions to some landmarks she used one of the maps they provide to show us the details. We folded it up and took it along.

As we walked along, I'd periodically take out my Palm Pre smartphone. Like the Apple iPhone, Android G1, and some other smartphones, it has browser-based Internet access, a GPS, and a custom Google Maps application. Did a particular subway train go where we wanted? Call up the transit authority's map and look. The browser-version has the same image as the printed map, but instead of fumbling with folding and unfolding you fumble with zooming and panning. Google Maps will show you where an address is (and the subway stops, too), and (thanks to the accurate and fast GPS) also where you are, updated in real-time as you walk. And it has all the streets, not just the ones the map maker decided were important enough to squish in. I would have needed to carry several folded maps (and a guidebook with museum hours, etc.) in my pocket to equal what I actually used on my phone, and I needed to carry the phone, anyway.

It is clear to me that once the big percentage of the population that has gotten dependent on cell phones for voice and short message communications upgrades, and gets used to, iPhone-level devices, the demand (and use) of those paper maps will all but disappear. Rumored upcoming purse-sized tablets should only hasten the disappearing process.

As I was walking, I got to thinking. The content I was accessing on my phone was sometimes the same as that on paper -- so much so that it probably came from the same PDF file or was derived from the same Adobe Illustrator image. The content was the same, but it was "printed" on a different substrate: It was bright dots on an LCD display instead of ink on paper. But the data, the "signal", was the same. It was just the carrier that changed. This got me thinking about signals and carriers and led to this essay.

Radio: Signals and Carriers
A short digression for those who aren't familiar with radio technology.

In describing how radio works, as I recall from my youth, there is often talk of a signal, such as the varying amplitudes of sound waves or the on-off of Morse Code, and carriers, such as the radio-frequency waves that actually travel through space. Here is how it works:

Sound waves don't travel very far. They usually travel through air and dissipate pretty quickly. The human voice has problems going more than a few hundred feet, especially outdoors. Even something as loud as thunder can only be heard for a few miles. Sound waves have a frequency in the range of maybe 20 to 20,000 cycles per second (called 20 Hz to 20 kHz) and are easily detected by humans using their ears.

Radio waves, by contrast, can travel much further, going dozens, hundreds, or thousands of miles and still are detectable with inexpensive equipment. They travel through air, space, and most structures such as buildings and trees. They have frequencies ranging from half a million cycles per second to billions of cycles per second (called, for example, 500 kHz to 50 GHz). They are not normally detectable by humans without use of special equipment.

What a radio transmitter does is produce a radio-frequency signal, such as a 550 kHz wave, and then "modulate" it by, for example, varying its intensity in step with a sound signal that varies at a much slower range. Here is an illustration showing the radio-frequency signal, the sound signal, and the combined, modulated radio signal produced by a common method:

A radio receiver does the opposite. It can detect the radio wave, and then recreate just the sound signal for listening:

The radio frequency wave is called a carrier, and the data it is modulated with (and that is recreated on the receiver) is called the signal.

From a technical viewpoint, there is often a major difference between the technologies involved with these two parts. While both radio frequency and sound frequency electronics use somewhat similar sounding parts (initially vacuum tubes and then transistors and such, resistors, transformers, wires, etc.), the specifications are quite different. The sound equipment is more concerned with its use by people in capturing, mixing, molding, and accurately reproducing the sound, and the aesthetics of the equipment. The radio transmitter is much more concerned with use of high electrical power, the quirks of how parts carrying radio waves interact and need to be isolated, and legal/standards issues because of the use of the "public airways". The people who design and build, and the people who use or maintain, the two types of equipment are often different, with different training and backgrounds.

Other Signals and Carriers
This concept of signals and carriers can be expanded to apply to other areas. The information and image of a map can be viewed as a signal and the folded paper on which it is printed can be viewed as a carrier. Likewise, the transit authority web page or Google Maps service can be viewed as other types of carriers carrying the same signal. The sound waves of a song can be viewed as a signal (and, other than the spoken human voice, can be viewed as one of the most prototypical ones) and the radio viewed as one carrier, with vinyl disks or CDs shipped by truck to stores and then bought and carried home as another carrier. Typed up words can be a signal, and paper carried from place to place by the US Postal Service can be a carrier, as can a fax machine, or email.

Changing Carriers
As you can see, while we often think of the signal and carrier as one complete entity, they are really quite separate. One type of signal (such as maps or typed communication) can be well carried by different carriers, and one type of carrier, such as bulk-printed paper or radio waves, can be used for different types of signals.

Sometimes we get so caught up in the nuances of a particular signal/carrier combination that we think that that carrier can only be used for that type of signal, or that the affordances of that carrier are necessary for that type of signal. This can be inappropriately limiting.

I remember, back in the 1970s, when we worked so hard to make computer-based word processing be as much like typewriter-based word processing as possible when it came to the output. Much work went into "letter quality" printing, so that you hopefully couldn't easily tell the difference between "computer" output and that from an IBM Selectric typewriter  (the "real thing"). Letters were still printed out, put in envelopes, and then carried by some sort of postal service. We were so proud that we didn't have that dot-matrix or line-printer computer look. Computer output could now be submitted even when there were strict quality or PR image requirements, and didn't need explanations when used for things like contracts and other legal documents.

At the same time, we went from needing to get documents "into the mail" by 5 pm and received sometime in the next day or so, to being able to be "Fedex'ed" as late as 8 pm and delivered by 10:30 am the next morning. This speedup in delivering the same "signal" was something people loved, and they spent orders of magnitude more to get that 200% or so improvement in delivery time over traditional mail.

Those assumptions about the need for perfectly formed characters got thrown out the window with the advent of the fax machine. Suddenly, if you were willing to accept a result of somewhat smudgy looking text (which was often worse than the old dot-matrix printers) and replacing handsome bond stationery with thin, curling, chemical-based "paper", you could send a typewritten page across town or across the world for the cost of a short telephone call. And, lo and behold!, those people we struggled to give letter quality took our gorgeous letter quality, bond-paper output and put it through fax machines, making those machines (and the voice telephone system) the carrier. And they were happy and readily bought those machines for $1,000 (which was worth a lot more in those days). The old signals -- typed, letter-sized pages -- got sent by a new carrier that replaced fidelity to the original (in the case of postal mail it was the original) with speed and low cost. Over time, the quality difference diminished, but that never seemed to be a major factor. In just a few years, faxes went from something only used by news organizations and other specialized services to something required to be acknowledged on your business card. A small business would be embarrassed not to have a "place you could fax to" and home-based consultants tried to hide the fact that their faxes printed out at the grocery store down the block.

Email changed things again. Initially, gone was the ability to precisely format the layout, or choice of fonts, or use of carefully designed letterhead. Gone was the clean look of the received message. In its place we got almost instant speed, easily added co-recipients, easy replies and forwards, and direct author to receiver messaging without the intermediate use of secretaries and other assistants. Again, users switched. In today's world, the email address has replaced the fax number as the required information, sometimes even replacing the "mailing" address.

Throughout this, though, many of the "signals" being carried by post, by fax, and by email are virtually identical. They were created by moving the same fingers on the same keyboard layout to write the same words and were read by people with the same skills almost oblivious to the change.

To the people in the carrier businesses, though, these changes were earth moving. Stationery printers went from a high volume mainstay to a niche. Fax machines went from something bought by few businesses to something produced in huge volumes and in demand by every business. After email caught on, fax functionality then dropped down to being something included as a minor option in multi-function machines that are more often used to print out email attachments or scan images for local reproduction or incorporation into electronic documents. Email went from something only for the most technical to something that makes the national news when there are disruptions.

What's the point of all this?
So, what is my point here? I think that people and organizations involved in different parts of the signal/carrier continuum need to think through carefully what changes we are seeing, and will soon see, that are coming about because of the ongoing march of technology. This is happening in a larger and larger range of areas. For any given signal, there are new options for which carriers can be used, and users are going to expect them to use those carriers and accrue the benefits that come with them. Like the sudden onset of demand for using fax, and the quick decline when email became ubiquitous, these changes can happen in just a few years after many years of gestation. Just because of a perceived inferiority by a new type of carrier in one aspect, the ubiquity and desirable features of the technology that makes it possible may cause users to ignore those shortcomings. A user may not buy a "pocket map reader machine" but they are already carrying a cell phone.

This is related to Clayton Christensen's Innovators Dilemma, which teaches about how the suitability of a disruptive technology for a niche use sustains it until it meets the wider needs of other uses and slowly replaces them as it goes up the quality curve. In our case here, the desirability of a new technology for a main purpose of a particular signal trumps secondary quality issues. In addition, other factors may create the ubiquity of the new carrier (brought about because of other uses, such as smartphones becoming ubiquitous because they are used as phones and email machines) so that it can be inexpensively deployed for new signals (such as subway maps). The switch to the new carrier is much quicker in these cases and can catch everybody by surprise. The step of the niche uses highlighted by the Innovators Dilemma may not be needed.

Organizations and people in a particular carrier business also need to watch this carefully. Their entire capital and distribution infrastructure may be quickly obsoleted when a major type of signal starts switching to be more commonly carried by a different type of carrier. The quality and price improvements they may have been working on may have little sway against the desirability of totally different attributes of the new carriers. Signal producers often give little thought to the fact that adding a new carrier may cause demand for the services of one of their carriers to drop. They concentrate more on serving their target users and look for new growth areas.

These carriers need to be constantly on the lookout for which other types of "signals" their systems can carry. There are questions to ask, such as: What else needs inexpensive multi-color printing on large sheets of paper? What other type of good needs to be distributed with that shipping latency to those outlets? What distinct competencies has the organization built up? Logistics? Fulfillment? Reach? Customer relations? What else can it be applied to? How should they shrink parts of the business? At what speed? (You can make money even in shrinking businesses, as we learned in business school in cases about the vacuum tube industry, but it is different than in growing fields.) What parts do they now emphasize with new types of "signals" to carry? Where do they invest? Which new technologies that can augment what they already have will be key to opening up new signals to carry -- technologies both on the signal side and the carrier side?

Too often an industry becomes too vertically integrated, where each of the points on the signal/carrier continuum are assumed to be part of single, God-given whole. As we are seeing, that is usually not the case.

For example, the "music business" does not intrinsically have plastic discs shipped in paper sleeves to store shelves as a part. Many years ago the music business used to include as a major part the production and sale of sheet music. That is now a much smaller part. It used to include cylindrical tubes, then vinyl disks, then tape, then CDs, but it also included the use of broadcast radio and live performances. Now people expect to carry their music stored on flash memory in their pockets. The whole carrier step of making a plastic disc with a set number of "tracks" and shipping that disc through so many hands is unneeded and actually a hindrance to the final placing of the sound file on those devices.

The Amazon Kindle system, with its use of cellular radio data transmission for distribution, is an example of replacing entire parts of the carrier system. The Kindle is not a perfect analogy to the situation with music. The Kindle sometimes ends up with a different form of the signal. The encoding technology it is currently using is not very good for material that depends upon specialized formatting or graphics nor is the display technology good for color. The music files carried by services like Apple iTunes, however, are identical to the files desired by the users for their music players. (Eventually, though, the types of written material suitable for electronic distribution will cover most of print as display technology evolves.)

The people in the music business each have to figure out which part of the signal/carrier continuum they are on and what is best for that part, splitting off from dependence on the other current parts. Signals need to look at additional carriers and carriers need to look for different signals to carry. Fighting this change in signals to carriers will just add unneeded, undesired (and eventually disliked) inefficiencies that will be uncompetitive against others who have switched to new combinations.

Some technologies that will bring big changes
This need to look at signals and carriers doesn't just apply to the tourist maps and the music business. Here are some technologies that will change the available carriers for different signals:

Smartphones and pocket tablets

Smartphones are becoming increasingly popular. These are devices you carry in your pocket, purse, or wear in a holster. They have screens that are large enough to provide a meaningful amount of information, detailed photographs, videos, etc. They have rich interaction modes, including touch screens of some sort, keyboards of some sort, audio input (a microphone), audio output (earphone and sometimes speaker), photo and video recording capability, and various forms of wireless connectivity. At the current adoption curve, such devices will become extremely common and will at some point become a dominant form of computing/communications carried by a large percentage of the population.

Another related class of device that looks like it may become popular over the next few years is the small tablet. These are envisioned as a hybrid of smartphones and netbooks. A small, low end version that is in use in large volumes today is the Apple iPod Touch (of which Apple reports they have sold over 20 million units).

As I pointed out with respect to printed maps, many signal types that are currently distributed on paper for carrying by individuals are subject to migration to smartphones and pocket tablets as carriers. Music, video, and games may also be popular on these platforms, though there are other platforms that will also be popular (such as portable music players and game machines in different form factors).

If you look carefully, and with an open mind, you will find other areas where these devices could replace (or lessen the need for) some other means. A not-as-obvious ability of these devices is to use the camera or microphone to identify objects (such as bar-code reading or music recognizing). This can cut out the need for other means to do the identification. Companies need to look at such devices in the context of their fields, since they may know the steps in the flow of their fields that may be ripe for being performed using such technology that may not be well-known or appreciated outside of the field.

Wall-sized screens

The prices of large flat-panel displays have been dropping for years, and their size and quality has been growing. You are finding large displays, connected to computers of some sort, in places where in the past you may have seen printed or painted paper posters, marquees (such as in hotel lobbies), projected images, or even whiteboards and blackboards. Technology for linking multiple displays together and driving them effectively to create huge computer display walls is progressing. This will affect display of relatively static as well as dynamic information. This technology is already becoming commonplace in public areas and is moving more and more into corporate (board room, conference room, and later individual room) and educational settings. For art work of certain types it might even soon move into the home.


The ubiquity and commonplace familiarity of interactive interfaces, especially Internet-based (both browser and dedicated applications on traditional or handheld computers), and the comfort people are getting with "just in time training" for accomplishing tasks the first and subsequent times, is making self-service a viable (and cost-effective) option for many things. The travel industry has been heavily affected by it, with self-serve researching of alternatives for travel and lodging, as well as self-serve purchasing and customer service, replacing travel agents, airline counter agents, etc. People routinely book flights, make changes, check in and print boarding documents, etc. They fluidly move from desktop browsers to kiosks to handhelds. Government is being affected, too, with more and more interactions able to be performed without a visit to a government office.

Collaboration technologies

Wikis, shared files such as on Google Docs and Adobe Buzzword, Twitter, Skype, and a host of other technologies are making collaboration at a distance very practical and very powerful. Activities that required time-consuming steps between people as part of the work flow can now be done orders of magnitude faster, or with orders of magnitude more participants.

Mechanical Turk

The Internet has made access to a dispersed workforce around the world inexpensive and quick. Work that requires individual attention by a person that can be broken into manageable chunks, such as transcribing a recording or designing something artistic, may be sent to a waiting workforce for bidding and performance. Computing power in general has made customization much less expensive in many areas, and these techniques also extend customization into other areas. (The name Amazon gave to their system for doing this, Mechanical Turk, comes from a late 18th century chess playing "machine" that turned out to be assisted by a person hidden inside the device who controlled an attached mannequin dressed in Turkish robes and wearing a turban.) This may change the balance between limited options and customization, and break down some barriers to personal attention in a 24x7 environment.

Crowd-sourced data

Images, audio, video, observations, opinions, and more are being made available for sharing electronically and for incorporation into specialized applications. This is giving us new signal sources. For example, if you want to see how certain dances are performed, or how certain songs are sung, or see comedy routines, or hear a certain genre of music, you can often find many examples on YouTube. Blogs and personal/educational/business websites give people access to information on almost any topic written by actual practitioners and researchers, not just reporters. Photos of events taken by numerous participants have changed how we document those events. You used to need a professional photographer to get good photos at a wedding or similar event. Then disposable film cameras made it practical for many of the participants to capture moments that the "professional" would miss. Today, with many of the attendees photographing the event for their own purposes from their own viewpoints, sometimes with equipment on par with that of the professionals, immediately after the event a very thorough documentation of the event is often available for all to share online. Some of these may capture moments that the newlyweds may want to incorporate into their "official memories" album.

Bandwidth marches on

The speed and ubiquity of connectivity, both wired and wireless, continues to improve. Each quantum improvement opens up new opportunities to carry additional data types or to take advantage of reduced latency. Retrieving a high quality digital image of a map on a pocket device as quickly as you could take a paper one out of your backpack and unfold it used to be impractical. Now it is the norm. What we used to produce all in one pre-loaded package can now be obtained on demand as one piece or piecemeal.

Storage marches on

Improvements in the capacities of storage in portable or affordable desktop/rack-mounted forms opens up new opportunities. We have seen handheld playback devices go from an 40 minutes or so of audio (CDs and tape) to hours of video, with the additional benefit of random access replacing linear access. Off-peak time can be used to cache data that you may or may not need in the future. Data can be captured without determining in advance if it will be needed in the future, and then the particular items we need may be retrieved quickly at a later time when we determine a need.

CPU power marches on

Computing power continues to improve, both in computational speed and in reduced power consumption. Data can be amalgamated locally instead of needing to be pre-processed in advance before moving from producer to consumer. An example of using this power is the common GPS unit, which continually performs real-time calculations on radio signals from satellites with variations in billionths of a second, and then mixes the results together with compressed map and store- and attraction-location data to produce a continually updating display as you drive or walk.

-Dan Bricklin, September 14, 2009

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