Looking for a handheld computer that combines formidable security features with the ultimate in ease of use? A mobile device developed for the U.S. Census Bureau could be your benchmark.

The platform--with technical specs and custom software developed by Harris Corp. and hardware built by Tai- wan-based High Tech Computer Corp. (HTC)--will be put through its paces starting today, when the bureau kicks off its "dress rehearsal" for the next nationwide head count. The field trial will deploy 1,400 of the handsets in Fayetteville, N.C., and Stockton, Calif.

When the Decennial Census takes place in 2010, some 500,000 of the devices will enable the first paperless effort to canvass addresses and follow up with residents who fail to return questionnaires.

Instead of paper-based address lists, maps and surveys, census field workers will use maps stored on the mobile device's Secure Digital (SD) card. They will use the unit to acquire GPS coordinates for each residence they visit and then wirelessly send the electronically collected responses to a Census Bureau data center.

Efficiency and accuracy are the main goals for the automated data collection program, according to Mike Murray, vice president of the census program for Harris. Near-real-time electronic collection and correlation of census data will let the bureau rapidly direct field workers to the right places for follow-ups with nonresponding households. The system will save not only paper, but also time and expense, by reducing the number of unproductive field visits, Murray said.

The mobile device's GPS function is expected to improve the accuracy of address canvassing. When a field worker finds a house on a map on the SD card and stands in front of it, the handheld's GPS function pinpoints the GPS coordinates of the structure and automatically sends that data to a data center.

The transmitted information goes so far as to pinpoint on which side of the street the residence stands, thus identifying the census block to which it belongs. That seemingly minor detail is sometimes critical for setting the boundaries of congressional districts.

"If the structure was a dormitory or an apartment complex and if you didn't have the accurate information, you could end up having hundreds of people registered in the wrong congressional district," said Murray.

On the surface, the handheld looks like HTC's existing smart phone. The handheld uses the Microsoft Mobile 5.0 operating system, running on a 416-MHz Intel Bulverde.

Although a number of components are reused from existing HTC models, Harris devised much more demanding technical specifications for the handset to improve usability and security for the census application, said Murray.

The resultant device incorporates a "brightness resistant" 3.5-inch QVGA LCD screen from Sharp Corp., a GPS chip from SiRF Technology that Harris calls "the most accurate chip on the market today" and a fingerprint authentication chip by AuthenTec Inc.

For operation even in harsh sunlight, Sharp's antireflective LCD offers 200-candela/m² performance, Murray said. "This increases brightness twice as much when compared with the 90-cd/m² screen used in Dell's Axiom handheld computer," he said.

As for the GPS, SiRF's chip enables accuracy to within 1.2 meters, bettering the 3-meter accuracy window Harris stipulated in its specs. The chip "enables the fast acquisition of signals, while it's capable of working in even a partially blocked area such as a doorway," Murray said.

Qualcomm Inc.'s MSM6500 chip equips the unit with high-speed cellular datacom capability based on CDMA EV-DO/1xRTT. Voice communication is not supported; field staff and crew leaders will communicate through text messaging.

Several redundancy and flexibility features are incorporated in the device. In case there is no cellular coverage in the area, for example, the handset comes with a dial-up modem.

It also incorporates a USB connector. While software upgrades customarily would be handled in small packets via a wireless network, "the USB connector is there just in case," Murray said, adding that anytime custom-developed software is involved, "glitches can happen."

Few standard mobile phones today offer fingerprint authentication, but in the case of the census device the utility is both an important security measure and an ease-of-use feature. A registered fingerprint becomes the field worker's access key, eliminating the need for workers to remember passwords.

Indeed, the standout feature may be the unit's usability. Ease of use is critical, since, in the field, the device will be deployed by workers with varying technical literacy who may range in age from 18 to 80.

Once a field worker collects data and is out the front door, the information collected is automatically sent to a data center without requiring the field worker to push a "send" button. "It's gone," even without the census worker's knowing, said Murray. Only partially completed data--an interrupted interview, for example--would be saved, in encrypted form, on the unit's SD card without being automatically transmitted, he said.

Data is encrypted upon collection via a Harris-developed software module running on the CPU. The encrypted data is then sent via private network to a data center. A Web portal at the data center makes the data available via a secure network to the regional census office. For encryption, Harris uses a U.S. government computer security standard: Federal Information Processing Standard Publication 140-2.

As for the cost, Murray said that Harris is still negotiating with HTC, but the program will be managed within the $600 million government contract Harris won as system integrator for field data collection automation. Harris won the contract a year ago, beating out finalists General Dynamics and Northrup Grumman.