The test found that an overwhelming majority of the phones under scrutiny would cause shortfalls in the audio quality of hands-free-supported conversations.
The test event, held at ITU headquarters May 12-16, analysed the performance of a representative sample of mobile phones available today and capable of connecting to hands-free systems. Of the phones tested, roughly 30 percent passed the tests, with the remaining 70 percent found to produce performance degradation that would be noticeable to drivers and conversational partners.
Serious faults were observed in the worst-performing phones; some causing as much as a three-fold decline in voice quality, others completely failing to acknowledge that they had been connected to a vehicle's hands-free system.
Quality degradation of this extent has led to customer complaints to the car manufacturers, and experts say could give rise to safety risks as it could encourage drivers to use their phone by hand while driving.
And in a plea to solve a persistent problem, major car manufacturers, including Mercedes and Toyota, with hands-free terminal (HFT) supplier Bosch, have issued a strong call to mobile phone manufacturers to adhere to standards, perform standardized tests on the behaviour of their products within hands-free systems.
"The results of these tests are illuminating and should encourage us to work together to make more interoperable products to serve our customers better. This is a real opportunity for industry and we fully support a collaborative approach that will create a seamless customer experience for all," said Fridjof Goebel, Daimler AG.
Automakers assert that there is little complexity to their requirements, asking only that mobile phones disable certain signal-processing functionality as they enter a vehicle's hands-free system.
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