Tough, versatile PDA platform for the military
(by Conrad H. Blickenstorfer)

The VT Miltope RPDA-1 is a modern, expandable and highly configurable rugged PDA clearly designed for military and other government applications, and in particular for the US Army CHS-4 (Common Hardware Systems-4) program.

Like a lot of computing hardware designed for military purposes, the RDPA-1 combines reasonably current COTS (commercial off the shelf) components, great configuration flexibility, and military standard ports into a unit designed to be compact, light and tough enough to provide real value, situational awareness, and a strategic advantage out there in the field.

What Miltope came up with to meet those demands is a PDA platform large enough to accommodate a 4.1-inch display and the requisite ports and connectors, but not so large as to weigh soldiers down. That said, the RPDA-1's 6.5 x 3.6 inch footprint is larger than that of even the biggest current consumer smartphone, and the device also weighs over a pound; there's just no way around that. It is also capable of being loaded with either Windows CE, Windows Mobile, Linux or Android. Finally, the military has different connectivity requirements, and the RPDA-1 meets those as well.

Covering so many bases means a platform that's as open as possible, which in turn means certain compromises. The processor, for example, must be able to run all those different operating systems. The Texas Instruments OMAP 3530 Miltope chose does that. It's a competent chip that's also used in such high-volume devices as Intermec rugged handhelds and also by some Winmate devices, but is not at the performance level of the speedy dual- and quad-core chips running in modern smartphones.

The choice of display and digitizer, likewise, must have been a difficult one. Windows CE and Windows Mobile were designed for use with a stylus, Linux can be anything depending on its shell, but Android definitely works best with capacitive touch. As is, the RPDA-1 seems to have a resistive digitizer, with the advantage being that it can be used when and where it's wet. As far as screen size and resolution go, both are adequate and a good compromise.

Providing for all the necessary and anticipated connectivity in a device like this is difficult as well. While a modern smartphone can do with a single tiny micro-USB port, a military device may have to accommodate numerous standards, and whatever ports are used must be waterproof and sturdy (which micro-USB definitely is not). As a result, there is a screw-on Taclink connector to talk to a Taclink modem, a surface-mount connector, and a 15-pin connector that presumably handles RS232 serial as well as USB host and client.

As the pictures on top of the page show, the RPDA-1 can be paired with the RPDA-1P PC Card expansion module or the RPDA-1S with a TACLINK 3000+ modem as well as an integrated SAASM GPS receiver with L1/L2 antenna as well as connectivity with external GPS antennae and serial interface equipment.

The RPDA-1 looks rugged, and it is. VT Miltope literature lists almost 20 environmental and EMI/EMC tests the device has been subjected to, so it's safe to assume that all the ruggedness criteria are covered.