Abstract: In accordance with one or more implementations, a method includes receiving, with an electronic device, a first satellite signal and a second satellite signal and determining whether the first satellite signal is LOS. The determining is based on a signal strength of the first satellite signal. The method also includes determining whether the second satellite signal is non-LOS. The determining is based on a signal strength of the second satellite signal. The method further includes estimating a location of the electronic device based on the first satellite signal and the second satellite signal in response to determining that the first satellite signal is LOS and that the second satellite signal is non-LOS.

Abstract: The present invention uses a map database which is created with the view of optimization in terms of size and complexity, so that it can be easily embedded into a navigation chip. The optimized map database is referred to as a “mini-map” database. The mini-map database easily integrates with the position calculation routine. The algorithm for position calculation includes a map-matching component, which is referred to as the “mini-map-matching” (MMM) algorithm, which is implemented on the navigation chip. Application of the present invention includes any navigation system for vehicles and/or pedestrians. The navigation system may include an inertial sensor, such as a dead-reckoning (DR) sensor, for further improvement in calculated positional accuracy when satellite signals are degraded due to environmental factors.

Abstract: The present invention uses a map database which is created with the view of optimization in terms of size and complexity, so that it can be easily embedded into a navigation chip. The optimized map database is referred to as a “mini-map” database. The mini-map database easily integrates with the position calculation routine. The algorithm for position calculation includes a map-matching component, which is referred to as the “mini-map-matching” (MMM) algorithm, which is implemented on the navigation chip. Application of the present invention includes any navigation system for vehicles and/or pedestrians. The navigation system may include an inertial sensor, such as a dead-reckoning (DR) sensor, for further improvement in calculated positional accuracy when satellite signals are degraded due to environmental factors.

Abstract: An improved time-to-first-fix (TTFF) for GPS systems is provided through a comparison of the time-of-week (TOW) to the sub-frame identification (ID). In one embodiment, this comparison comprises dividing the TOW to form a ratio and performing a modulus operation on the ratio to form a remainder, which is then incremented. If the incremented remainder equals the sub-frame ID, the TOW is assumed to be valid, thereby providing a time of transmission. The time of transmission may then be used to calculate pseudoranges and determine a receiver's location.

Abstract: An improved time-to-first-fix (TTFF) for GPS systems is provided through a comparison of the time-of-week (TOW) to the sub-frame identification (ID). In one embodiment, this comparison comprises dividing the TOW to form a ratio and performing a modulus operation on the ratio to form a remainder, which is then incremented. If the incremented remainder equals the sub-frame ID, the TOW is assumed to be valid, thereby providing a time of transmission. The time of transmission may then be used to calculate pseudoranges and determine a receiver's location.