Abstract: A source device includes various sensors, such as a GPS receiver. The source device provides operation context data to a server that indicates movement of the source device. The source device may also provide a movement context. The server also evaluates usage of data from the device by other applications or devices to determine a usage context. Based on the movement, operation, and usage contexts, the server selects a frequency at which data is collected for a sensor and a frequency at which the data is transmitted to the server. For example, where the device is not moving or is indoors, less location data is collected. Where no user is tracking the device, location data may be transmitted less frequently and may also be collected less frequently.

Abstract: A source device includes various sensors, such as a GPS receiver. The source device provides operation context data to a server that indicates movement of the source device. The source device may also provide a movement context. The server also evaluates usage of data from the device by other applications or devices to determine a usage context. Based on the movement, operation, and usage contexts, the server selects a frequency at which data is collected for a sensor and a frequency at which the data is transmitted to the server. For example, where the device is not moving or is indoors, less location data is collected. Where no user is tracking the device, location data may be transmitted less frequently and may also be collected less frequently.

Abstract: The present invention provides a buffer circuit for providing constant impedance to a transmission line in an integrated circuit. The buffer circuit includes an output terminal, an input terminal, a power supply terminal, a virtual voltage terminal, a first switching element, and a second switching element. The input terminal includes a first terminal and a second terminal for receiving a binary logic signal. The first switching element is connected between the output terminal and the power supply terminal. The second switching element is connected between the output terminal and the virtual voltage terminal. The circuit includes switching control logic for turning on and off the first and second switching elements in a complementary manner in response to the binary logic signal. The circuit further includes compensating logic for increasing output impedance to the output terminal. In the buffer circuit a layout of the driver circuit can be easily implemented with an optimized driver area.