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Issue 11, Fall 2003


Inside This Issue:

Review our Previous Issues

SSS is proud to present our Eleventh Online issue.

We are now soliciting ideas and articles for our twelfth issue, which is tentatively scheduled for mid-winter. Please send your comments and suggestions to:

What's New At Pegasus Technologies and SSS Online

Check out Pegasus Technologies' new RF Module Sales page. We've got a lineup of nifty RF modules in a variety of frequencies and prices for sale. These range from our top-of-the-line PTSS2003 915 MHz transceiver, which has an onboard microcontroller and has FCC and Canadian modular certification, to more basic RF-only modules in 433 MHz, 868 MHz, and 915 MHz. A development kit fot the PTSS2003 is also available. New modules are in development, including an 868 MHz version of the PTSS2003 and a brand new 2.4 GHz module with onboard microcontroller.

You can purchase these modules and accessories through our online store, with secure checkout available that accepts Visa and Mastercard. Of course, you can also go the phone-in route and get your questions answered at the same time. We can customize these modules as well, and offer full technical support for getting them incorporated into your application.

In other news, SSS Online, Inc. has just completed its third year of ownership of this website. We've completely revamped all the pages now and are adding new, up-to-the minute content on an almost daily basis. We've not done too well keeping up with our change directory, but hope to get it back on track this fall to make it easier to find new things on the site. In the meantime, we've installed a Google site search that is really nifty, and some news feeds on hot items like UWB that make it easy to stay up with what's happening right now.

We're always on the lookout for good, new articles for publication in the Ezine or elsewhere on the site. We can't pay cash, but have been known to barter free advertising in return for articles -- so if you've got one you'd like to see get some wider exposure than it might otherwise get, drop us a line at . We're always happy to hear your comments on any aspect of our website!

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UWB Still Struggles as IEEE is Unable to Agree on Standard in Singapore

by Jim Pearce
President, Pegasus Technologies, Inc.

In recent months, the UWB battlefield has moved away from the FCC to the IEEE in its standards-making role. The 802.15.3a Committee, which has until August 2004 to develop a radio standard that can transmit data at speeds of 110 Mbit/s over 10 meters, has been considering 21 different standards proposals to meet these objectives, which are over a hundred times faster than today's comparable Bluetooth standard (about 1 Mbit/s over 2.4GHz).

In July, the committee held its first vote and whittled down the field of contenders to two: the multiband OFDM (MB-OFDM) proposal sponsored by the MultiBand OFDM Alliance (Texas Instruments, Intel Corp, and 14 others), and a proposal backed by a team including XtremeSpectrum Inc. (XSI), Motorola, and ParthusCeva.

The MB-OFDM proposal splits the FCC authorized ultrawideband spectrum into three or seven bands to boost performance to 660Mbps over five meters or 188Mbps over ten meters. The XSI/Motorola proposal advocates a continuous spectrum.

At the July meeting, the MB-OFDM proposal won a majority of the votes, but fell short of the 75% necessary for adoption. Shortly after this meeting, XSI and Motorola filed a request for a declaratory ruling with the FCC, contending that the multiband proposal does not comply with the FCC's regulations. FCC's Deputy Chief of the Office of Engineering and Technology, Julius Knapp, ducked the issue in early September, saying that a ruling was "premature" because IEEE deliberations were still continuing. Knapp doesn't rule out further FCC involvement in this issue at a later time, however:

We urge that IEEE perform technical analyses to ensure that any UWB standard it develops will not cause levels of interference beyond that already anticipated by the rules. This information will be needed to support any necessary FCC rules interpretations or other appropriate action for the chosen standard.

We recommend that IEEE proceed with its standards development process and that the committee address any questions to us at a later time when it has formed a specific proposal.

Opponents to the multiband approach also object that it does not guarantee zero-royalty intellectual property licensing, only a "reasonable and fair" licensing policy, and have raised issues about the fairness of the IEEE process. XSI and Motorola contend that a private meeting in Denver between multiband proponents and members of the 803.15a Committee was not legal under IEEE bylaws because single band proponents weren't invited. The multiband group contends that XSI et al aren't open to compromise, and that the meeting would not have been productive had they been invited. The XSI group disagrees with this contention.

Both proposals were again considered at the Committee's meeting in Singapore on September 14-19. The MB-OFDM proposal again garnered about 60% of the votes, which leaves the selection still open. A final decision could now be made in November at the Committee's next meeting in Albuquerque.

Intel added another twist to the mix by stating that if a favorable decision on MB-OFDM isn't reached soon, they might break off from the IEEE committee to pursue a proprietary approach to UWB. Speaking before the Singapore meeting, Pat Gelsinger, Chief Technical Officer at Intel, said that Intel is considering creating a special interest group (SIG) to set a standard independent of the IEEE. "If agreement isn't reached in the next three meetings we may consider an alternate strategy such as a SIG," he said. "We have strong confidence of getting it if not this time, then in November or at the subequent meeting. Nothing else is close."

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Wi-Fi Wrangle Resolved

By Patrick Chisholm

Patrick Chisholm is managing principal of PolicyComm, LLC, a provider of research, writing and editing services for IT companies and other businesses. He is a regular contributor to Military Information Technology magazine, where an earlier version of this article was published.

Without sufficient safeguards, increasingly popular wireless networking technology could interfere with vital military radar systems. However, DoD, NTIA, and industry representatives have been successful in working out a compromise that will protect these interests while allowing increased use of spectrum for commercial uses. International consensus on these issues was reached at the World Radiocommunication Conference held in Geneva this past June and July.

The rapid rise of wireless networking technology has revived tensions between the military and private industry over access to the radio spectrum. The two camps have worked out their differences on the domestic front, and have now been successful in getting foreign governments on board as well.

But 802.11a operates at radio frequencies between 5 GHz and 6 GHz, and therein lies a problem. Such wireless-fidelity (Wi-Fi) transmitters can cause significant interference with military strategic and tactical radar systems that also operate between 5 GHz and 6 GHz, unless appropriate interference protection mechanisms are in place. As many as 10 types of Department of Defense-run radar systems could be affected, such as systems used for missile guidance, aircraft monitoring and storm tracking.

The military particularly wants to ensure that 802.11a does not hinder its ability to pick out smaller and less reflective radar targets amid background clutter, such as airplanes and small boats that terrorists could use to attack U.S. military targets. The Department of Defense (DoD) is also concerned about its ability to detect stealth aircraft, which can elude most conventional radar systems.

Department officials initially sought to limit the use of wireless LANs in the lower portion of the 5 GHz frequency band. Industry viewed this as too conservative, but the two camps were able to work out a compromise solution. The compromise enabled the United States to formalize its position with respect to 5 GHz wireless, and present that position to the recent World Radiocommunication Conference (WRC) which took place this past June and July in Geneva.

Sponsored by the International Telecommunications Union, WRCs are held every two to four years to achieve international agreement on major radiocommunication issues. The US delegation to the four-week conference consisted of a dozen team members supported by over 30 FCC staffers in various technical and policy areas.

The conference, attended by representatives from more than 140 countries, established voluntary national security communications guidelines and made new allocations of airwave spectrum for such uses as Wi-Fi and broadband-in-flight, according to a July 10 press release from the FCC. "The results of WRC-03 will further advance the digital migration to new spectrum-based technology platforms and further protect homeland security," said FCC Chairman Michael Powell. "It is important to understand why the Defense Department takes spectrum allocation proceedings so seriously," Steven Price, Deputy Assistant Secretary of Defense for spectrum, space, sensors and C3 policy, told a congressional hearing last year. "Spectrum is the life blood of the Department of Defense. We use terms like 'beachfront property'-that's how valuable it is."

Over the past 10 years, Price said, DoD and other federal agencies have begun to relinquish 247 MHz of prime spectrum to industry.

"Every reallocation of spectrum essential to military capability from DoD reduces flexibility, requires that replacement equipment be purchased or a work-around developed and erodes our realistic training." The official continued, "While we recognize that there are many competing needs for spectrum, including needs for commerce, important national defense needs must be a top priority."

The 802.11a issue is far from the first spectrum-related conflict between DoD and industry. Another technology that has been debated is Ultra Wideband (UWB), which had the potential to disrupt global positioning system (GPS) operations enough to degrade the ability to navigate and land military aircraft, as well as to train with precision-guided munitions.

But that problem got worked out, according to Michael D. Gallagher, Deputy Assistant Secretary of Commerce and Deputy Director of the National Telecommunications and Information Administration (NTIA). NTIA, DoD, the Federal Communications Commission, private industry and others finally agreed on a solution so that UWB does not negatively impact or interfere with GPS, said Gallagher.

While DoD is NTIA's toughest, most detailed and most technical customer, Gallagher added, "We work very hard to make sure they are fully protected at the same time as we provide for our economic security."

Proliferation of 802.11a

The 802.11b standard, which operates in the 2.4 GHz band, poses no conflict with DoD radars. And, as yet, there have been no known cases of interference involving 802.11a. "But everyone is looking forward," said Scott Blake Harris of the Washington, DC, law firm Harris, Wiltshire & Grannis, who represents a number of high-tech companies on matters involving technology regulation. "They see the enormous success of 802.11b, and anticipate 802.11a will be a similar success-and there is no reason to think it won't. So both DoD and the private sector have to plan for the future."

Wi-Fi uses "hubs" or "hot spots" to provide wireless Internet connections to users with Wi-Fi cards in their computers. The first 802.11a-based products, consisting of access points and radio network interface cards, were shipped to market in 2001.

Early this year, the Wi-Fi Alliance-the nonprofit industry consortium that certifies 802.11-based networking products for interoperability-certified the first wave of 802.11a products. In another sign of their growing popularity, Intel is developing its Banias mobile PC platform, which will contain integrated dual-band Wi-Fi (802.11 a and b) wireless networking.

But the rise of 802.11a means it could eventually crowd the radio frequencies that the military uses. And one thing appears certain: DoD will not be moving its radars to another frequency to make room for 802.11a.

The department has invested tens of billions of dollars in radars in this band, and replacing them would require hundreds of billions of dollars, according to Badri Younes, director of spectrum management at DoD. Moreover, there is no comparable spectrum to go to, Younes said, adding that radars have lost hundreds of megahertz in the past few years, and that further losses would compromise national security.

"Further degradation to our radar capabilities would have a severe impact on our ability to win wars and protect our forces and allies," he warned. "Radars represent the eyes and ears of our military forces, so how can we purposely take away their sight and hearing and still expect them to perform?"

Younes explained that DoD supported a new international allocation of 200 MHz for Wi-Fi devices in the 5150 MHz to 5350 MHz band, with a new interference mitigation technology to protect essential military systems. Industry already has 100 MHz of spectrum available in the 5800 MHz band, plus 83 MHz of spectrum for wireless access devices in the 2400 MHz band. The new international allocation of 200 MHz will provide industry with more than 380 MHz of spectrum to support Wi-Fi markets now.

DFS Debate

Domestic industry and regulatory bodies have expended much effort in the last two years to determine if sharing is feasible between DoD radar and wireless access devices. The answer lies in automated interference mitigation systems, particularly Dynamic Frequency Selection (DFS).

DFS refers to circuitry within the wireless LAN device that monitors for radar beams operating within the same channel. If such a beam is detected, it switches to another channel. These devices are already used in Europe, and are expected to be in use in the United States soon.

Early this year, the government announced that it reached an agreement with domestic industry representatives on the U.S. position with respect to 5 GHz wireless devices, for use in international forums.

The debate between industry and DoD revolved around how sensitive the DFS technology should be. Defense officials want high sensitivity-higher than that currently used in Europe-in order to protect its radars. But industry was concerned that constant channel switching would compromise the quality of service, as well as impede the availability of wireless Internet services. It also could have forced a complicated redesign of new and existing computer communications systems.

The trick, said Harris, was to find the "sweet spot" where communications equipment will work effectively and where radar is adequately protected. "We worked with NTIA, DoD and the FCC and finally determined where that sweet spot is." In areas with strong radar signals, the achievable DFS technology would surely be sensitive enough, said Harris.

"What we're working with is the worst case, where the radar signal is weakest, and the 802.11a equipment could still have an impact on the radar. DoD understandably wants to make sure that the emissions from an 802.11a device do not interfere with the radar, so the device has to be sensitive enough to recognize the radar signal. The challenge was to figure out how to make it sufficiently sensitive and still allow the 802.11a equipment to work," Harris continued.

The changes to the U.S. position allowed the United States to seek a mobile allocation at the WRC this summer in both bands sought by industry (5150-5350 MHz and 5470-5725 MHz), while ensuring protection of vital DoD radars.

Broadband Guidelines

Senators George Allen, R-VA, and Barbara Boxer, D-CA, recently introduced a bill aimed to help jump-start the broadband Internet market by expanding access to broadband technology. It requires the FCC to make more broadcast spectrum available for use by Wi-Fi devices by dedicating at least 255 MHz of spectrum below the 6 GHz band for the unlicensed use of such devices. The measure also directs NTIA to develop guidelines in order to avoid signal congestion and interference in the dedicated spectrum, stipulating that no interference with military uses occurs.

Meanwhile, DoD officials emphasize that they understand the need for a balance between military and economic security. Regarding DoD's proposal to support a new international allocation of 200 MHz for Wi-Fi devices in the 5150-5350 MHz range, Younes commented that the proposal "provides a reasonable amount of spectrum now to enhance the market for Wi-Fi technology, while ensuring successful sharing capabilities that will support additional growth of the Wi-Fi market in the future while protecting essential military capabilities."

Gallagher of NTIA added that a solution would be worked out. "We did it with Ultra Wideband, we did it with 3rd Generation Mobile Telecommunications, and both of those were unsolvable according to the trade press and participants up to that point in the process. We applied the leadership and the hard technical analysis necessary to solve these problems, and we're going to do it again with 5 GHz."

Looks like Gallagher was right, and we all look forward to the continued cooperation between the affected parties around the world. It's heartening to see that these issues can be resolved!

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FCC Proposed Rulemaking to Modify Part 15 and Part 2 Rules

by Jim Pearce and Karen Edwards
Pegasus Technologies, Inc.

US Capitol

In case you haven't seen it yet, the U.S. Federal Communications Commission (FCC) has issued a proposed revision to Parts 2 and 15 of the rules for unlicensed devices and equipment approval. The Notice of Proposed Rulemaking was released September 17, 2003, and comments are being accepted for 30 days following publication in the Federal Register. You can see the text of the rulemaking in pdf format here on our site, or here on the FCC site. To keep up to date on the comments as they are received, you can go to the FCC's Electronic Comments Filing System and enter "03-201" in box 1, "Proceeding". Then press the "Retrieve Document List" button at the bottom of the screen. This will bring up a list of documents that have been filed, and .txt files of all comments and FCC documents on this topic. There aren't many yet, but that won't be true for long!

We're still reviewing the details of the proposals, and preparing our own comments, but initial reading indicates that these changes are (for the most part) a good step in the right direction. In addition to soliciting comments on specific changes proposed, the Commission has issued an open invitation for comments on additional ways they might improve spectrum sharing among unlicensed devices.

Key changes in the proposed rules would --
  • Permit the use of advanced antenna technologies ("smart antennas") with 2.4 GHz spread spectrum devices;
  • Modify the replacement antenna restriction for Part 15 unlicensed devices;
  • Modify the equipment authorization procedures to provide more flexibility to configure transmission systems without the need to obtain separate authorization for every combination of system components;
  • Harmonize the measurement procedures for digital modulation systems authorized pursuant to Section 15.247 of the rules with those for similar U-NII devices authorized under Sections 15.401 - 15.407;
  • Modify the channel spacing requirements for frequency hopping spread spectrum devices in the 2.4 GHz band in order to remove barriers to the introduction of new technology that uses wider bandwidths; and
  • Clarify the equipment authorization requirements for modular transmitters.

A brief summary of each of the changes, and some of our initial thoughts, are summarized below.

Advanced Antenna Technologies
Currently, the rules only provide for use of omnidirectional and point-to-point antennas, and set limits on the amount of directional gain that may be used by each type. New technologies, such as sectorized antennas and phased array adaptive antennas, could use spectrum more effectively by making it possible to re-use a given frequency to communicate with different devices along non-overlapping paths.

The Commission is proposing to allow these types of antennas to operate within the higher limits currently allowed for point-to-point antennas. The proposed rules would define characteristics that antenna systems must meet in order to be eligible for these higher limits, and would limit aggregate power transmitted simultaneously on all beams to 8 dB above the limit for an individual beam. FCC is also seeking comments on whether there should be a maximum E.I.R.P. limit for each individual beam, and if so, what the limit should be. And finally, they're asking for comments on whether the current compliance testing requirements (compliance measurements must be taken with all radiating sources emitting) make sense for all types of advanced antenna technologies.

We have some concerns about whether low-power applications within the 2.4 GHz band, such as industrial remote control and data acquisition, might be affected by the proliferation of the relatively high- power WISP signals that are likely to result from this change. We believe that the 5.8 GHz band is a more appropriate frequency for the operation of toll WISPs, and that the advanced antenna technology modifications proposed here should be allowed for that band and not for 2.4 GHz.

Replacement Antenna Restrictions
Section 15.203 requires that intentional radiators be designed in such a way that no antenna other than the one supplied can be used with the device. This was an attempt to ensure that the Part 15 emission limits aren't intentionally circumvented by replacing the supplied antenna with another one with higher gain. FCC is proposed to modify this requirement to require testing with the highest gain antenna of each type that would be used at maximum transmitter output power. Any antenna of a similar type that doesn't exceed the antenna gain of the tested antenna(s) could be used on that transmitter without retesting and approval.

The proposed antenna flexibility seems to mirror the flexibility already exercised in the existing modular certification. If the intent is to make all Part 15 certifications similar to modular certification, we feel that this is a beneficial change.

Flexible Transmission System Configuration
As the current rules require equipment authorization for every combination of a transmission system, it is not possible to mix and match components without extensive retesting. This has an impact on wireless internet service providers (the so-called WISPs) and limits their ability to design systems that meet the needs of the particular application without the additional time and expense of retesting. The Commission is proposing a series of changes to the rules that would permit professional radio systems installers to configure systems using technically equivalent components without requiring retesting of the specific system selected. This puts a greater burden on the technical competency of the systems installers to ensure that their systems meet FCC regulations, but will enable both quicker deployment and lower costs for WISP services.

This should help WISPs to provide alternative high-speed connections in rural areas where DSL and cable services are not available. We're particularly interested in this one, since our Webmaster's office is still dealing with a 56k modem! However, we do not understand why FCC maintains the position that "The 'professional installation' provision ... may not be applied to modules." Seems to us that professional RF engineering staff at OEMs are far more technically competent than the standard "professional radio systems installer" and should be able to make similar configuration decisions with regard to the use of modules while developing commercial products.

Also, we are concerned that the use of external RF power amplifiers under the provisions of 15.247 may open Pandora's box of escalating interference and violation of FCC rules. Even with the current state of the rules, it is possible with minimal effort to locate sellers of amplifiers that appear go beyond established limits. If a mix and match approach is taken to transmission systems operating under 15.247, such amplifiers will become vastly more prevalent. It will be trivial for manufacturers to "throttle back" the output power of their amplifiers for meeting the rules, but have a user accessible control that would allow the "professional radio system installers" to set the output power many times higher than is permissible. This could even become a "whisper spec" for such devices.

Measurement Procedures for Digital Modulation Systems
Devices that operate in the 5.7 GHz band are currently limited to a maximum power output of 1 watt. However, output power for devices that operate under the Part 15 U-NII rules are measured differently than for those that are under section 15.247 spread spectrum rules. This proposed change would make measurements the same for both types of devices - and would use the average measurement of output power (U-NII) rather than the peak emission method currently used for spread spectrum devices.

The FCC is also asking whether the different limits on peak power spectral density between U-NII devices and Section 15.247 devices are appropriate, and if not, which of the two limits should be applied.

Frequency Hopping Channel Spacing Requirements
The Bluetooth SIG suggested a modification of the channel separation requirements for FHSS systems, and FCC is proposed to adopt this suggestion for 2.4 GHz systems with an output power limit of no more than 125 mW. Current rules require a separation of 25 KHz or the 20 dB bandwidth of the hopping channel, whichever is greater. The Bluetooth SIG suggestion is for 25 KHz or 2/3 of the 20 dB bandwidth, whichever is greater, for devices operating in the 2.4 GHz band. This would permit Bluetooth devices to be capable of data rates of up to 3 Mbps.

We think this is a great idea, and one that should be expanded beyond the 2.4 GHz band. Why not 915 MHz as well?

Modular Transmitter Approvals
Modular certification of transmitters can save time and money in incorporating wireless capability into many different devices. A certified module can be plugged into a number of devices without requiring FCC certification of each device. The 2000 Public Notice entitled "Part 15 Unlicensed Modular Transmitter Approval" detailed 8 criteria which must be met in order for the FCC to grant certification for modular transmitters. However, this notice did not contemplate the development of a new class of "partitioned" modular devices that are currently under development. These new modules have a radio front end and a firmware component that controls the radio operation. These can both be self-contained units. Also, in some cases the oscillator, tuning capacitors, and antenna are further partitioned to allow greater flexibility in mixing and matching individual components within different devices.

FCC is proposing to update the 2000 criteria on modular certification to address partitioned modules, and intends to incorporate these criteria into the Part 15 rules. An additional requirement is to be added, that would require that only firmware and radio front end equipment that has been tested together can be used together. In addition, comments are sought on alternative methods of demonstrating compliance with FCC rules.

We applaud the concept of this change, but think the FCC could cause confusion with their use of the term "firmware." Firmware applies to software programs or data that is stored in non-volatile memory. It's a combination of hardware AND software. A processor (such as a microcontroller) is NOT firmware, although a microcontroller that has built-it program storage memory (such as flash ROM) may include firmware.

It appears that the FCC intends firmware to mean the element that controls the RF front end. They could end the confusion by using the term "control element" instead.

Spectrum Sharing
The FCC is asking for comments on how spectrum sharing in the unlicensed bands can be improved, and specifically whether the spectrum etiquette provisions that apply to unlicensed PCS devices should be expanded to cover other types of unlicensed devices. We are not in favor of this. Many of the current applications in the unlicensed bands are low-cost, transmit-only devices that do not have the capability of implementing spectrum etiquette without substantial modifications and increased costs. We are concerned that this may result in stagnating the development and deployment of these devices.

There's a whole lot more "meat" in these rules than the brief summary I've provided here, and the potential for impact on our industry is very high. So, if you have a stake in these rules, you need to get out your magnifying glasses and fine tooth combs and take the time to make your comments. The FCC is trying hard to be responsive to the wireless industry's needs, but they need our help and input to make sure that the rules don't needlessly limit development and deployment of new technology.

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Review of the Hemisson PIC-Based Robot

by Jim Pearce
President, Pegasus Technologies, Inc.

I remember the first time I opened up a Swiss watch when I was a kid. (I was always opening up things to see what made them tick!) The beauty of the jewels, the shinning silver and gold metal, and the polished surfaces made a life-long impression that the Swiss people really know how to do thing right.

Hemisson is no exception! The Hemisson robot is a teaching tool for the principles of robotics aimed at students aged 10 to 15, and for hobbyists of any age who are interested in learning more about the principles of robotics and artificial intelligence. The Hemisson is about five inches in diameter, made of blue foam, and contains a PIC16F877 microcontroller, two motors, four LEDs, six switches, eight infra-red proximity sensors, an Infra-red remote control port, a buzzer, and an RS-232 port. It is designed to accept a number of extension modules that expand its capabilities even further.

The built-in firmware has several preprogrammed modes of operation that will let you play with Hemisson straight out of the box. In addition to "avoid the wall" and "follow the line" programs which are fun, I especially liked the hypocycloid dance mode. If you put a felt tip pen through the hole in Hemisson's middle and place him on a piece of paper while in this mode, he will draw pretty designs. The robot can also be operated through a standard TV remote control or via an RS232 cable connected to your computer. I found setup to be easy and performance was good, although you do have to be careful with sunlight and incandescent lighting, which can confuse Hemisson. Also, in the obstacle avoidance mode, he avoided some types of obstacles better than others.

The full potential of Hemisson is achieved with the Bot-Studio and Webots-Hemisson. Bot-Studio is a finite state machine programming language that runs on a PC and that downloads the compiled instructions to Hemisson. This allows many rules for the motion of Hemisson to be defined and easily executed. The firmware is open source which allows for modifications to suit your particular applications.

My 15 year old son played with Hemisson straight out of the box and had fun with its preprogrammed modes. He was not able to understand the FSM programming without help from me. I suspect that he is not unusual in this regard. For a class project or other environment where an adult can guide the children in learning robotics, the Hemisson should provide a worthwhile platform. For hobbyists who are already familiar with some level of programming, it should be easy to learn and a great way to expand your knowledge of robotics and AI.

The manual provided enough detail to get you started, and was relatively clearly written although obviously not by a native speaker of English. It includes a summary description of the microcontroller and a link to find out more information about its capabilities, and a schematic (although it was hard to read because it was so small). The documentation on the CD Rom was also adequate, and there is a website ( that offers more information, a newsletter, and a users forum.

A variety of modules that extend the capability of Hemisson are available now. One of these is a radio module that permits wireless communications with your PC, and another is a tiny linear camera that mounts on top of Hemisson and allows it to perceive its environment in a more sophisticated manner. For hobbyists, there's an interface board to make it easier to install your own electronics. Additional modules are under development. We didn't try out any of these modules, but they look like they could be fun.

Hemisson is designed, manufactured and distributed by K-Team S.A., a Swiss company that develops, manufactures and markets not only the Hemisson, but also the Khepera Linecard, high-quality mobile minirobots for use in advanced education and research, and KoreBot and Kameleon, advanced miniature single board controllers for the automation industry.

Prices start at $275.

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Job Search Spotlight
Marketing Yourself with Internal and External Promotions

by By Teena Rose,

Teena Rose is a certified and published résumé writer with Résumé to Referral. She is the author of "Résumé Designs and Job-Search Strategies for College Grads", scheduled for publication by CareerEpublications in September 2003. She is a regular contributor to SSS Online.

Surveys have shown that up to 80% of those employed are unhappy. Unhappiness results from being overworked/underpaid, a deteriorating relationship with colleagues or management, or possibly, disappointment in oneself. If you plan to sell your time and abilities, why not take complete advantage of your efforts? Being in control of your career and promoting yourself can dissolve dissatisfaction by providing more career options and opening more doors to opportunity.

Volunteering on committees or with non-profit organizations (whether internally or externally), or offering your capabilities when your employer shows a need is a great way educate yourself on new topics. While learning on the job or within a volunteer position, you'll likely uncover opportunities through continued personal growth or by networking with individuals you wouldn't have met through your existing channels. Added responsibilities will show management that you are serious about saving the company money, or that you care about your community. Executives and business managers want to see measurable results from employees, so I recommend making the effort to step up to the plate.

The benefits of self-marketing can far outweigh the costs -- the time needed to do so. I'll outline just how in this story about a salesman. If a sales rep out-produces colleagues with over $2 million in yearly sales, then the company probably won't mind paying upwards of six figures to keep this employee happy, right? The company is experiencing a very favorable return on investment, and the employee is trained, independent, and compensated well. It's a win/win situation.

The question now is how did this sales rep turn into an asset. After all, out-producing colleagues is not an easy feat. I'll tell you exactly how this person went from a mediocre $50,000 salary to over six figures in less than 2 years.

First, he took the initiative to participate in evening classes on various sales topics, such as relationship building, new selling techniques, and identifying the aspects that provoke decision makers to buy. Did the company pay for these classes? No. He saw the need for improvement and jumped at the chance to enhance his education and produce more revenue for the company.

Second, he focused on external marketing techniques by sending personal press releases upon obtaining key accounts (more notably known as "People on the Move" within business sections of newspapers and other publications), participating on non-profit committees, and so on.

One opportunity was particularly beneficial. He elected to serve on a high-profile committee and found himself talking to a secretary who reported to the Director of Business Development for a prominent technical firm. Ironically, his company had been pursuing this corporation without success for over 5 years. He gradually built a relationship and eventually landed the account that produced nearly a million dollars in new revenue for his business.

Committee meetings were on his personal time and not compensated. Marketing yourself to the community can enhance your existing job or job search tremendously because companies like to see employees that I'll label "movers and shakers." These individuals don't wait for things to happen, they make them happen.

Third, he documented all career successes and solidified his position in the industry. Documentation can consist of letters from superiors or customers, awards, and/or performance bonuses.

When seeking a raise, he created a presentation that focused on the amount of new revenue he cultivated for the business over the last 12 months and compared it to the proposed new salary. The company would be crazy to refuse his request, in my opinion. If they did, he would subsequently work for a competitor making him an adversary rather than an ally.

Taking a proactive approach, rather than being reactive, is what catapulted this person to a six-figure salary. Prove yourself an asset to your employer. Make them unable to live without your expertise, your devotion, and your overall dedication to ensuring the company's financial health and customer loyalty.

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