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Preprints & Reprints Beam Me Up - I Really Want to be Mobile If ever I had a dream of mobile communication it was fuelled by my Tuesday night experiences as a student in the 1960s. Tuesday nights were special, the dorm would be packed with anticipation, people waiting to see James T Kirk beam down to some unknown planet. His first act was always to confirm safe arrival through his flip top communicator. This remarkable device worked convincingly with the occasional twist of a rotary knob to fine tune and avoid static. At that time mobile radios used by military, police, emergency services and cabs still employed thermionic tubes and were the size of a briefcase. So, what Captain Kirk had was barely believable. Thirty years later Jean Luc Pickard just wears a badge - and a stroke his hand is all it takes to contact anyone or anything of choice. Communication is always clear and concise; no numbers to remember; no directories, buttons to push, or knobs to adjust; all very easy and natural to use. But this dream is now much closer; today we have mobile phones the size of chocolate bars that cost almost nothing, and networks that cover over 90% of all major countries. But remember, only a decade ago, the first cellular phones were the size and weight of a small briefcase, and the so called pocket phones, the size of a house brick. So perhaps we are catching up with the future! Among the smallest devices now available are Dick Tracy style wrist phones (at $1500), and some to be announced will be jewellery like - worn as a part of clothing. In all cases the primary physical limitations to size are power (batteries), keyboard and display - in that order. And the key user problems are poor (over complex) interfaces, background acoustic noise, cell coverage, and channel availability due to increasingly chaotic demand for access. Multi-function displays and buttons, and an assumed microphone-to-ear distance half that of a human head, often seems to demand unnatural acts in terms of just switching on, making contact, and talking. Buttons with 5 or 6 functions are not uncommon in this race to reduce size, production costs, price, improve reliability, whilst increasing the number of seldom used facilities. More critically still is full functionality irrespective of country, location, or service provider. In Europe the GSM system means that a 100% roaming ability with speech and data connections at 9.6kbit/s is the norm. Connecting your lap top, organiser, camera or other device into Internet or an Intranet is no longer a problem. In fact - this article comes to you direct from the Ipswich to London Inter-city train at over 90mph via an Intranet connected to Iternet. But it could have also been transmitted from my car, a cab or coffee shop. The only inconvenience is; the separate devices, connecting cable, limited power capacity and weight. In the fixed terminal market there is a migration toward a wide ranging integration of functionality that is now evident for mobile terminals too. Lap tops already have built in modems, and soon the entire digital phone will be integrated into the one device. So it is size and weight that plays a key limiting role. Soon we may have a species of human with longer arms and shorter sight as result. However, the market has already seen compact devices, such as the Nokia 9000 combining a pocket organiser and a GSM telephone, and more will follow. So - what happens next? Moore?s law will see chip density doubling at <18 month intervals for at least another decade and probably more. So computers will become >1000 times more powerful, and complete mobile phones and modems will be realised on a single chip. But there are more fundamental changes afoot. Firstly; there is voice command and control, that may do away with the need for both keyboard and mouse. It may also get rid of the screen for many applications. Secondly; there are new display technologies that could change the entire nature of the interface and the box. Thirdly, there is the very nature of networking and interaction between people and machines. Where are we going to locate the intelligence in future? It will have to be everywhere - we will carry some, and networks will provide us with the rest. In the forefront of this revolution today is the new programming language Java with Applets on demand. This relies on networks that are ubiquitous, reliable and low cost. In the time frame of development this has to be the telephone network - it is all we have. So what will be able to do - what kind of terminals could be engineered in the short and long term? It is already possible to talk to a machine to gain directory advise, buy and sell goods. But when we are on the move, background acoustic noise from car, train and people is a major limiter. The simple addition of a lightweight headset with noise cancelling is an obvious and long awaited addition for those who want to drive, ride, walk and talk. But then there are other possibilities, such as adaptive noise cancellation using one ore more microphones, with single and multiple phased speakers adapting to create acoustic bubbles. Active feedback acoustic (howl around) suppression, and constant sound level relative to background noise is also possible to negate the variation due to head position and location. So the Star Trek 23rd Century badge communicator now looks feasible. Mobile computing will also see a revolution in distributed network intelligence to realise a minimal portable hardware requirement. But again - spoken command and control will improve the usability whilst reducing overall cost. The primary attraction of such a future is the ubiquitous and general access to everything, anywhere, anytime, in any form, at low cost. When coupled with an interface simpler than a VHS, such a box will see a market of people previously frozen out of the information world by the horrors of the PC. Some estimates put this underprivileged majority as high as 80% of the population - it is a huge market. Users will also see the advantage of continual software updates at low cost over the network, instead of being sold a stream of upgrades to product that never fully worked when first purchased. For the more powerful mobile terminals there are new applications in the medical, engineering, insurance and many other sectors. For example, in recent experiments Nurse Practitioners have been able to vring the expertise of GPs to bear at remote sites - with a standard GSM phone, lap tops, and miniature TV cameras. Dermatalogical examination, foetal scanning, remote diagnosis, minor operations and emergency ambulance paramedic support from hospitals to the point of need have also proved possible. Probably the most revolutionary move will be towards the wearing of technology. Just like the carriage clock of 300 years ago - that became a pocket watch, and then a wrist watch, the cameras, computers and communicators can all be worn as items of clothing, jewellery and body furniture. So everything from roving news and sports reporting, to precise surgery and insurance loss adjusting can be done with a minimal amount of technology. Throughout all of these possibilities there is one underlying limitation - power! Although power requirements will fundamentally reduce as the integrated circuits and functions are optimised, the radio transmitter will still demand ~0.5W. A reasonable estimate for the total power demand for a combined computer -communicator is around 2.5W. If we add a screen, this can be at least doubled. However, for head mounted displays we my only require 0,25W. Our conditioning and expectation of display technologies is so dominated by TV it is hard to break free. Why use an electron gun to write on a phosphor that the emits photons that hit the retina of our eye? Why not fire photons straight into the eye? We now have lasers and are no longer limited by the CRT or LCD. Why not take over the retina by direct illumination rather than the limited window of a conventional screen? Whilst we cannot, yet, mount a laser on a contact lens (as this is currently precluded by the device line width necessary) it is possible to mount them on spectacle frames to give a head up display. Combine this with an ear mounted device for audio and the near cyborg communicator is born. So what other functions might we desire in our new mobile world? We could have broadcast radio, TV, information services, and of course Email and net access. But there is more. Satellite mobile services are coming, and the ability to flip between terrestrial and satellite would be an advantage, as would a GPS receiver to give us precise navigational data. Everything in the information world direct to our head - just by asking. All of the technology described exists in the research phase somewhere. The single most neglected item is power - batteries and charging. Nothing much is being done in industry - and we are coming to the end of the road. Assuming we could get away with 5W as an average, then the best results for a thermal vest - torso heat to electricity conversion - is <1W. As for kinetic energy - walking and swinging your arms and legs - is ~2W. In both cases these solutions currently mean being wired into your clothes, and do not justify the discomfort. It is still better to carry a bag full of batteries. So a programme on new materials and energy storage, and or generation, may be required to realise a really mobile future. Most of the mobile services and connectivity can be achieved using the Plain Old Telephone Service and cellular radio. So where is the next great challenge? More people going mobile means more chaos in the mathematical sense. We will see more people in cells than networks can cope with due to computer aided meetings, traffic jams on freeways, social and public events. There will also be a growing demand for more bandwidth. At this point the laws of physics are in our favour. Moving radio communication up from the 1 - 2 GHz region to 24, 60, 120 and 180GHz would realise sufficient bandwidth in atmospheric absorption peaks that naturally preclude communication over more than 100 - 1000m. The perfect micro-cell! But there is a new option; optical wireless has been made possible by the revolution in fibre systems. Devices working in the 1300 and 1500nm windows can provide cells of room, desk and chair size with razor sharp definition. The higher frequency (~300THz) means much greater precision and bandwidth. In experiments with these technologies bit rates of 100 - 1000Mbit/s to the pocket and wrist have already been demonstrated. If I were a young engineer just starting out I would find this an irresistible future. From the need for new chip technologies, robust speech interaction systems, to the engineering of head mounted displays, body worn units, power generation, network intelligence and switching algorithms, to the creation of new wireless systems using optics to generate carriers above 60GHz, or spread spectrum on optical carriers, I could have a ball. Right now I think I would choose to work on solving to power problem, I really would like an air conditioned vest. Torso heat to power, with my computing and communication technology distributed over its surface. I really do want to stop carrying technology and start wearing it. Or will it be wearing me? |