Navigating the Antenna Challenges of Miniaturized Telematics Devices

Delphi is a global supplier of electronics and technologies for automotive and commercial vehicles. The company delivers real-world innovations that make automotive products smarter and safer as well as more powerful and efficient.

When Delphi was looking to make a new miniaturized telematics device, it needed an antenna partner that would not only deliver the best cellular and GPS performance, but would also help to get product certification and network approvals first time. Some miniature wireless devices are installed underneath the glove compartment of a car in front of the passenger’s knee and need to be small enough to fit compactly into the diagnostics port in the vehicle. Delphi’s new wireless device had two challenges; it was less than half the size of a cell phone, but required AT&T network certification, which is based on a cell phone-sized products. Added to this, the device had stacked PCB boards, which act as a large capacitor and bring down antenna performance and efficiency.

Delphi needed an antenna provider for the small telematics device that could meet the challenges and deliver high antenna efficiency in these harsh conditions. Delphi chose Taoglas the M2M antenna provider, because of its antenna expertise, understanding of U.S. network certification processes and because Taoglas could design an antenna and optimize the whole system for TIS and TRP testing (receive and transmit sensitivity). “We had integrated antennas in similar cellular miniaturized wireless devices before so, we were familiar with the territory,” said Dermot O’Shea, director, Taoglas. “This device however, presented us with a new challenge.” Taoglas worked closely with the Delphi engineering team to figure out the requirements for the device and then custom-built a quad-band cellular antenna, the PCS.01 and a custom-tuned GPS active patch antenna module, the AP.25H.07.0040A.dn.

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“It was difficult to get high performance inside the device because it was so small,” commented O’Shea. “When you get down to that size, the small ground plane leads to efficiency challenges. In order to ensure top antenna performance, we collaborated with the Delphi team to optimize the whole device as a send and receive system to minimize the loss from an RF aspect. Devices of this kind present an added challenge with tacked boards, which have a huge impact on the antenna. It’s probably the most difficult environment to place an antenna when you consider all the M2M products in the market today.”

The PCS.01 was successfully integrated into the telematics wireless device and passed AT&T network certification first time. “It was a fantastic project to work on,” said O’Shea “It presented us with many challenges, but we met them head-on and engineered a top-class antenna. Bring on the next antenna challenge.”