Introduction

The introduction of a range of GPRS and GSM i-modules from INSYS Microelectronics now enables Diamond Point International's customers to design advanced vehicle tracking systems using the latest communications technologies.

When integrated with Diamond Point's Lassen® iQ or SQ GPS (Global Positioning System) modules from Trimble, the new GPRS (General Packet Radio Service) i-modules combine the most reliable ‘always connected' wireless communications with advanced GPS location technology. Such highly- integrated designs are now possible from Diamond Point for applications such as navigation, vehicle tracking and recovery, and vehicle movement monitoring and control from a central traffic control location. The GPRS and GSM i-modules, and GPS modules are however available separately for customers that are undertaking in-house designs.

GPRS facilitates instant connections, allowing information to be sent or received immediately as demanded by the GPS system. No dial-up modem connection is necessary. Immediacy and data rates up to around 115 kbps are key benefits of GPRS when compared to Circuit Switched Data services on GSM networks.

The Lassen LP provides a choice of data protocols, including TSIP, TAIP and NMEA for maximum flexibility. It also incorporates an antenna detection and protection circuit to monitor the condition of the antenna system.

Using Trimble's Lassen LP Schedule Track™ operating mode, the system can be programmed for quick power-up, automatic wake-up to maintain current satellite data for the fastest possible satellite acquisition, data gathering, location computation and position output to a schedule. Following this sequence, the module is powered-down to a standby mode of operation to achieve minimal power consumption. While in standby mode, the system monitors the receiver for the required incoming location confirmation message and powers-up to respond. In standby mode, the original requirement laid down an operational battery life of 24 hours. The finished design from Diamond Point delivered 40 hours of battery life, more than sufficient for the task.

System control for the GPS and GSM circuits via a serial interface was implemented using an 8-bit microcontroller. Diamond Point engineers wrote the application software in Assembler using just 2kB of code to keep RAM memory size to a minimum.

Phil Taylor, component sales manager EMEA, for Trimble Navigation, said "We have a long-standing relationship with Diamond Point at both managerial and engineering levels. The company was an excellent choice to handle this project, as it has outstanding experience and expertise in both GPS navigation and GSM modem technologies."

"The project, which was the culmination of several month's of intense work, proved to be quite demanding, requiring more capability to complete than initially conceived," said Sherman Kemmer, managing director of Diamond Point International. "It was however very rewarding and demonstrated our ability to fuse together GPS and GSM technologies in a single original system, something which other companies were not able to undertake," he added.

Engineering specialists from Diamond Point are able to provide integrated customised solutions for the widest range of embedded designs using Trimble GPS modules and a host of other products from leading embedded computing suppliers.

Product Links

Insys i-module GSM/GPRS
Trimble Lassen iQ
Trimble Lassen SQ
Trimble Lassen LP