| abstract |
A portable, handheld GPS unit ( 10 ) is operable to generate a track log corresponding a track traversed by a user and display a track display representative of the track traversed. The track display includes at least one track characteristic indicative of a feature sensed by at least one sensor ( 26 ) coupled with the GPS unit ( 10 ). The track characteristic of the track display varies in response to a change in the feature sensed by the sensor. For example, the track display may display a track of varying width, such that an increase in the track's width corresponds to an increase in the feature, and a decrease in the track's width corresponds to a decrease in the feature. Alternatively, the characteristic may be a track color change or a symbol indicating a predetermined amount change in the feature. The sensed feature may include altitude, distance, heart rate, temperature, light intensity, and oxygen content. In a first preferred embodiment, the sensor ( 26 ) is an altimeter ( 26 ) for determining an altitude of the GPS unit ( 10 ). In a second preferred embodiment, the sensor ( 126 ) is a sonar transducer ( 126 ) for determining a depth of a body of water. In a third preferred embodiment, the sensor ( 226 ) is a heart rate monitor ( 226 )for determining a heart rate of the user. Additionally, the GPS unit ( 10 ) may be combined with a plurality of sensors ( 26, 126,226 ) for determining and displaying an indication of multiple features sensed by the sensors ( 26, 126,226 ). |