| 摘要 |
<p>A self-test methodology verifies the satisfactory operation of an installed vehicular telematics unit (12) using a signal processor (22) of the telematics unit (12). The test can be initiated at any time by a vehicle occupant or a remote call center (24). When testing is initiated, the telematics unit (12) places a cellular call to the call center (24) or a phone simulator (30), which generates a test tone that is reproduced in the vehicle cabin through the audio output (46) and loudspeaker (18) of the telematics unit (12). The telematics unit (12) uses its microphone input (20/48) to sample the reproduced tone (38), and a signal processor (22) within the telematics unit (12) analyzes the sampled tone by performing a SINAD or equivalent calculation (40). The test evaluates the sound quality of the telematics unit (12) and verifies operability of the antenna, phone, audio and microphone components (16, 14, 18, 20).</p> |
