Circuit for estimating position and orientation of a mobile object
A circuit system for estimating position and orientation of a mobile object based on lights from a plurality of external light sources. The circuit comprises a position-sensitive light sensor for detecting the light sources and generating a first signal, an analog filter and amplification module (“AFA”) for filtering and amplifying the first signal and generating a second signal, a digital signal processor (“DSP”) for generating a coordinate system by extracting frequency components from the second signal.
1. A circuit system for estimating position and orientation of a mobile object based on lights from a plurality of external light sources, comprising:
a position-sensitive light sensor, said sensor being disposed to detect said light sources and generate a first signal;
an analog filter and amplification module (“AFA”), said AFA being disposed to filter and amplify said first signal and generate a second signal;
a digital signal processor (“DSP”), said DSP being adapted to generate a coordinate system by extracting frequency components from said second signal.
2. The circuit system of claim 1 , wherein said position-sensitive light sensor comprises a quad photo diode detector (“PD”).
3. The circuit system of claim 1 , wherein said position-sensitive light sensor comprises a plurality of photodiodes.
4. The circuit system of claim 1 , wherein said position-sensitive light sensor comprises a plurality of position-sensitive detectors (“PSD”).
5. The circuit system of claim 1 , wherein said DSP generates said coordinate system by extracting frequency components from said second signal and calculating where said lights from said light sources are detected by said position-sensitive light sensor.
6. The circuit system of claim 4 , wherein said DSP extracts said frequency components by using the Goertzel algorithm.
7. The circuit system of claim 4 , wherein said DSP extracts said frequency components by using FFT.
8. The circuit system of claim 4 , wherein said DSP extracts said frequency components by using DFT.
9. The circuit system of claim 1 , wherein said AFA comprises:
a transimpedance amplifier (“TIA”), being disposed to amplify said first signal from said position-sensitive light sensor to generate its output;
a first passive high-pass filter (“1 st PHP”), said 1 st PHP being disposed to remove DC bias from the output of said TIA and generate its output;
a passive notch filter (“PNF”), disposed to remove noise signals between a predetermined range of frequencies from the output of said 1 st PHP and generate its output;
a first gain amplifier, coupled to said PNF, being disposed to amplify the output from said PNF and generate its output;
a second passive high-pass filter (“2 nd PHP”), being disposed to remove DC bias from the output of said PNF and generate its output;
a second gain amplifier, coupled to said 2 nd PHP, being disposed to amplify the output from said 2 nd PHP and generate its output;
a passive low-pass filter (“PLP”), being disposed to remove signals above a predetermined frequency from the output of said gain amplifier and generate its output.
10. The circuit system of claim 9 , said AFA further comprising:
a first buffer, coupled between said 1 st PHP and said PNF, disposed to reduce interaction between said 1 st PHP and said passive notch filter.
11. The circuit system of claim 10 , wherein said first buffer is an op-amp configured as a voltage follower circuit with no gain.
12. The circuit system of claim 9 , wherein said PNF is implemented with detuned values to widen said predetermined range of frequencies.
13. A circuit system for estimating position and orientation of a mobile object based on lights from a plurality of external light sources, comprising:
a position-sensitive light sensor, said sensor being disposed to detect said light sources and generate a first signal;
an analog filter and amplification module (“AFA”), said AFA being disposed to filter and amplify said first signal and generate a second signal, said AFA comprising:
a transimpedance amplifier (“TIA”), being disposed to amplify said first signal from said position-sensitive light sensor to generate its output;
a first passive high-pass filter (“1 st PHP”), said 1 st PHP being disposed to remove DC bias from the output of said TIA and generate its output;
a passive notch filter (“PNF”), disposed to remove noise signals between a predetermined range of frequencies from the output of said 1 st PHP and generate its output;
a first gain amplifier, being disposed to amplify the output from said PNF and generate its output;
a second passive high-pass filter (“2 nd PHP”), being disposed to remove DC bias from the output of said PNF and generate its output;
a second gain amplifier, being disposed to amplify the output from said 2 nd PHP and generate its output;
a passive low-pass filter (“PLP”), being disposed to remove signals above a predetermined frequency from the output of said gain amplifier and generate its output;
a first buffer, coupled between said 1 st PHP and said PNF, disposed to reduce interaction between said 1 st PHP and said passive notch filter;
a second buffer, coupled between said PNF and said 2 nd PHP, disposed to reduce interaction between said PNF and said 2 nd PHP;
a digital signal processor (“DSP”), said DSP being adapted to generate a coordinate system by extracting frequency components from the output of said PLP.
14. A circuit system of claim 13 , wherein said first buffer is an op-amp configured as a voltage follower circuit with no gain.
15. A circuit system of claim 13 , wherein said PNF is implemented with detuned values to widen said predetermined range of frequencies.
16. A circuit system of claim 13 , wherein said DSP generates said coordinate system by extracting frequency components from said second signal and calculating where said lights from said light sources are detected by said position-sensitive light sensor.
17. A circuit system of claim 16 , wherein said DSP extracts said frequency components by using the Goertzel algorithm.
18. A circuit system of claim 16 , wherein said DSP extracts said frequency components by using an FIR filter.
19. A circuit system of claim 16 , wherein said DSP extracts said frequency components by using an IIR filter.
20. The circuit system of claim 13 , wherein said position-sensitive light sensor comprises a quad photo diode detector (“PD”).
21. The circuit system of claim 13 , wherein said position-sensitive light sensor comprises a plurality of photodiodes.
22. The circuit system of claim 13 , wherein said position-sensitive light sensor comprises a plurality of position-sensitive detectors (“PSD”).