A method for measuring the sensitivity of a capacitive proximity sensor and an application using the sensor as a proximity detector in mobile phone antennas is presented. 2D sensor data plots were physically more exact for tuning sensor placement. 3D sensor data plots were suitable for sensor intensity comparison, highlighting sensor differences in multiple sensor applications and effects in sensor`s output due to shadowing mechanical objects. The antenna proximity sensor was measured and optimised with sensitivity measurements. In a PIFA application the antenna load could be detected from both sides and from above the antenna on a scale o 4.03•10-14 F to 4.33•10-14 F. The cases present all possible positions of holding a phone used in either the ``calling'' or ``browsing'' mode. The method and the application emphasise the physical sensitivity and electrical fields of the sensor. The characteristics can be further improved by using other sensor types, sensor data fusion and advanced imitation of multisensory spatial interaction by humans and animals.
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