GPS RF front end and related method of providing a position fix, storage medium and apparatus for the same
A GPS RF front-end is disclosed comprising an antenna for receiving GPS signals, an analog to digital converter for sampling received GPS signals and interface circuitry for outputting the GPS signal samples. The GPS RF front-end is configured to vary the sample resolution of GPS signal samples outputted. Also disclosed is a corresponding method of providing a position fix, storage medium and apparatus for the same.
1. A GPS RF front-end comprising:
an antenna for receiving GPS signals;
an analog to digital converter for sampling received GPS signals; and
interface circuitry for outputting the GPS signal samples characterized by the GPS RF front-end being configured to vary the sample resolution of the GPS signal samples outputted;
wherein the sample resolution of the GPS signal samples outputted is varied in accordance with an instruction received from outside the GPS RF front-end.
2. A GPS RF front-end according to claim 1 wherein the sample resolution of GPS signal samples outputted is varied by discarding some samples initially taken prior to output.
3. A GPS RF front-end according to claim 1 further comprising analogue signal processing means for filtering and down-converting the received GPS signals to an intermediate frequency for sampling; and wherein the filtering and/or down-converting is varied with varying of the sample resolution.
4. A method of providing a position fix comprising the steps of:
receiving at least two sets of GPS signal samples having different sample resolutions outputted from a GPS RF front-end;
processing those GPS signal samples to determine a position fix;
issuing an instruction to the GPS RF front-end to vary the sample resolution of GPS signal samples outputted.
5. A method according to claim 4 wherein the instruction to the GPS RF front-end to vary the sample resolution of GPS signal samples is made based on a mode of processing of the GPS signal samples.
6. A method according to claim 5 wherein the mode of processing of the GPS signal samples is one of either signal acquisition or signal tracking.
7. A system comprising:
a processor;
a memory for storing instructions, which when executed by the processor perform the steps of:
receiving at least two sets of GPS signal samples having different sample resolutions outputted from a GPS RF front-end;
processing those GPS signal samples to determine a position fix; and
issuing an instruction to the GPS RF front-end to vary the sample resolution of GPS signal samples outputted.