Mobile Handheld Interface to Satellite Transciever

Product

This piece of software runs on a variety of handheld devices, with and without barcode scanners, that are used by people in the trucking industry to enter data on their shipments, as well as to communicate with their dispatchers regarding specific deliveries. The driver is able to send and receive messages (in the same style as email) from the device, whether or not it is docked with the device "docked" in the cab or roaming around the back of the truck.

What we provided

The problem here was replacing an always-wired terminal by something that could be carried around by the driver, yet would provide access to previously received messages and allow queueing of new messages even while disconnected from the multimode satellite terminal. In addition, it had to provide all of the functionality of the fixed terminal it was replacing, including the ability to reconfigure the satellite communication parameters.

This problem could have been solved in a number of ways, but we were operating under the constraint of not knowing in advance much about the handheld devices in question. As different trucking companies have selected devices from different vendors with different capabilities, we wanted a solution that would give us access to the widest variety of devices with minimal work involved in adding new ones.

The solution we fixed on was to use a Web-style interface. Web browsers are now available on all Windows-based laptops, Windows CE devices, PocketPC handhelds, as well as Palm devices. In order to implement this, we had to add a TCP/IP stack to the embedded satellite terminal, equip it with a web server and provide access to its communications mechanisms through Internet-style email. We installed on each handheld device a proxy server which the built-in browser communicated with. This proxy server, in turn, was responsible for maintaining certain pages in a local cache, and exposing the local sent and received mail as web pages. This allowed the interface to remain web-based even when the device was disconnected from its TCP/IP link with the satellite terminal.

The resulting system has two different starting web pages, one for protrait-format screens, the other for landscape-format screens. All the other pages are shared among all the devices from different manufacturers, which include HP, Casio, Intermec, Symbol, Palm, and Melard.