Handheld U.S. Kenaz R100|
When you need GPS in your super-rugged TDS Recon handheld computer
(by Conrad H. Blickenstorfer)
The Handheld Group, located in Sweden and founded in 1997, is a worldwide suppliers of ruggedized handhelds for use in markets such as utility, military, logistics, forestry, transportation and field service. Handheld has a full lineup of rugged tablet computers and rugged industrial PDAs. One of the unique and interesting products they offer is the Kenaz DGPS receiver.
The Kenaz addresses a very specific need: what do you do when you have a Recon or Nomad handheld computer and want to use them for GPS/GIS applications without giving up any of the ruggedness and sealing that those devices carry? Those familiar with the Recon know that you can get an extended CF-Cap for it that enables the Recon to accommodate a variety of oversized add-on cards that sue the CF form factor and interface. That cap can be used in conjunction with, for example, a Holux SiRFstart III GPS card that is also available from Handheld U.S.
However, in many precision agriculture, marine, GIS mapping, surveying and a variety of other applications, a combination of ruggedness and heavy-duty commercial GPS technology is required, and that is where the Kenaz comes in. The Kenaz is based on Crescent receiver technology that is known for razor-sharp sub-meter accuracy, and being able, via COAST technology, to maintain that even during a temporary loss of the differential signal. The GPS engine used in the Kenaz code employs phase measurement and multi-path rejection that make for a very accurate and stable receiver.
Among the standard and extra-cost firmware features and options of the Crescent GPS technology used in the Kenaz are:
COAST Technology, which facilitates minimal position drift during temporary differential signal corrections loss and maintains sub-meter accuracy for up to 40 minutes after the signal loss.
- RTK, or Real Time Kinematic, satellite navigation, which offers the same sub-inch accuracy as dual frequency systems, but at much lower cost (RTK needs a base station, rover, and correction transmission at a one-time activation fee).
- L-Dif technology, that provides sub-foot accuracy and a variety of exclusive L-Fid- exclusive techniques (needs a base station, rover, and correction transmission at a one-time activation fee).
- e-Dif Extended Differential, which limits position drift when differential corrections are unavailable and has recalibration options to regain absolute accuracy at a reference location. There is a one-time activation fee, but no subscription costs.
- RTCM Base Station functionality that essentially converts the GPS receiver into a differential Real Time Correction Messages station.
The Kenaz comes in two parts (see picture above). There's a special CF adapter that replaces the standard Recon cap, and then there is the completely sealed Kenaz receiver itself. The connection between the two is via ultra-reliable spring-loaded pins. By default, the Kenaz connects to the device on COM2 at a baud rate of 57600. It can be used with a wide variety of mapping, GIS, surveying and other GPS-based software available via Handheld U.S. or from third parties.
The Kenaz's internal smart antenna is sufficient for most applications, but there's also a sealed external SubMiniature B SMB snap-on connector (see on large picture in the righthand sidebar) for an optional external antenna for additional accuracy or antenna placement in conditions where the unit itself may be obstructed.
Bottom line: Anyone who bought their Recon not only for its features and performance, but also for its exceptional ruggedness (4-foot drop spec, IP67 sealing), and who needs to retain this ruggedness even after adding a high-sensitivity GPS receiver should take a look at the Kenaz. This is likely the most rugged total GPS-enabled handheld solution available on the market today.