Public Transportation Service Application

Industry: Public Transportation System
Product: Wireless Serial Server (GW51W-MAXI) with Customized Firmware
Site Location: North America (from Dec. 2006 until now)

Case Overview

More and more cities around the world use non-contact IC card readers to collect fares of buses, subways, and parking. This application story happened in North America, where the bus service is operated by a private company who has to submit the rider’s fare records, what collected by the on-board IC card reader, to municipal government for the payments. The on-board IC reader contains also information of fare rates and black-name list of lost IC cards which needs updates from time to time. So the bus driver used to pull out the IC reader and carry it to the operation center to upload/download the data with the built-in RS232 port, at the end of every round trip. It’s very inconvenient and inefficient.

Application requirements

1.  With the additional wireless serial server, the card reader can upload and download the data automatically.
2.  The wireless serial server must wait for at least 1 ms before transmitting another byte to the card reader, as is required by the particular card reader.
3.  The wireless serial server must be well designed for the demanding operational
environment on buses, specifically the wide range of temperatures, possible long time excessive sun lights, constant vibrations, and occasional and violent shocking.

System Topology

What was done by Atop

1.  Device F/W modification – Atop engineers spent a few days to modify the F/W according to the requirement of the customer. The updated GW51W-MAXI (new version now is SW5001) is released for the customer’s testing. After a few weeks of revision and testing, the device started operational stably.
2.  In the early operational stage, a few APs (more than 3) were installed to provide the coverage of a large parking area. As there are only 3 non-overlapping channels available in the 2.4GHz band, radio link exhibited occasional breakdown due to the channel interferences. Atop provided improvement advices after on-site survey.
3.  To further minimize the radio link problem, Atop modified the F/W to facilitate better error-recovering.
4.  The whole process took nearly 6 months from the initial inquiry to stable operation.

Business Benefit

About 200 pieces of GW51W sold and project still under going.

Key Success Factors

1. Fast F/W customization and good engineering support.
2. Working closely with the local system integrator to solve problems timely.

Business Opportunity

Fleet Management – Many fleets of long range buses and trucks are equipped with GPS for tracking and navigation, using the same solution the GPS tracked data of the buses and trucks can automatically uploaded to the fleet management center when they are back to the stations.

Product Wireless Serial Server with Customized Firmware
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