Method for determining location of wireless devices

A method for determining a location of a mobile station relative to an access point having a known location, comprising:

• receiving, by the mobile station, at a first reception time a first signal from a first antenna of the access point;
• receiving, by the mobile station, at a second reception time a second signal from a second antenna of the access point having a known distance from the first antenna;
• determining, by the mobile station, a phase difference between the first signal and the second signal;
• determining, by the mobile station, an angle of a straight-line path extending from a midpoint of a first line between first antenna and the second antenna to the mobile station and a second line that is perpendicular to the first line at the midpoint based on the first reception time, the second reception time, and the phase difference between the first signal and the second signal;
• and
• determining, by the mobile station, a location of the mobile station based on the known location of the access point and the angle of the straight-line path.

A method for determining a location of a mobile station relative to an access point having a known location, comprising:

• receiving, by the mobile station, at a first reception time a first signal from a first antenna of the access point;
• receiving, by the mobile station, at a second reception time a second signal from a second antenna of the access point having a known distance from the first antenna;
• receiving, by the mobile station, at a third reception time a third signal from a third antenna of the access point having known distances from the first antenna and the second antenna;
• determining, by the mobile station, a first phase difference between the first signal and the second signal;
• determining, by the mobile station, a second phase difference between the first signal and the third signal;
• determining, by the mobile station, an angle of a straight-line path that extends from a midpoint of a centroid between the first antenna, the second antenna, and the third antenna to the mobile station and a perpendicular line that extends through the midpoint of the centroid based on the first reception time, the second reception time, the third reception time, the first phase difference between the first signal and the second signal, and the second phase difference between the first signal and the third signal;
• and
• determining, by the mobile station, a location of the mobile station based on the known location of the access point and the angle of the straight-line path.

A mobile station comprising:

• a wireless transceiver;
• and
• a processor coupled to the wireless transceiver and configured with processor-executable instructions to:
• receive at a first reception time a first signal from a first antenna of an access point having a known location;
• receive at a second reception time a second signal from a second antenna of the access point having a known distance from the first antenna;
• determine a phase difference between the first signal and the second signal;
• determine an angle of a straight-line path extending from a midpoint of a first line between first antenna and the second antenna to the mobile station and a second line that is perpendicular to the first line at the midpoint based on the first reception time, the second reception time, and the phase difference between the first signal and the second signal;
• and
• determine a location of the mobile station based on the known location of the access point and the angle of the straight-line path.

A mobile station comprising:

• a wireless transceiver;
• and
• a processor coupled to the wireless transceiver and configured with processor-executable instructions to:
• receive at a first reception time a first signal from a first antenna of the access point;
• receive at a second reception time a second signal from a second antenna of the access point having a known distance from the first antenna;
• receive at a third reception time a third signal from a third antenna of the access point having known distances from the first antenna and the second antenna;
• determine a first phase difference between the first signal and the second signal;
• determine a second phase difference between the first signal and the third signal;
• determine an angle of a straight-line path that extends from a midpoint of a centroid between the first antenna, the second antenna, and the third antenna to the mobile station and a perpendicular line that extends through the midpoint of the centroid based on the first reception time, the second reception time, the third reception time, the first phase difference between the first signal and the second signal, and the second phase difference between the first signal and the third signal;
• and
• determine a location of the mobile station based on the known location of the access point and the angle of the straight-line path from the perpendicular line that is parallel to at least one of the first antenna, the second antenna, and the third antenna and extends through a midpoint of the centroid between the first antenna, the second antenna, and the third antenna to the mobile station.

A non-transitory processor-readable storage medium having stored thereon processor-executable software instructions configured to cause a processor of a mobile station to perform operations comprising:

• receiving at a first reception time a first signal from a first antenna of the access point;
• receiving at a second reception time a second signal from a second antenna of the access point having a known distance from the first antenna;
• determining a phase difference between the first signal and the second signal;
• determining an angle of a straight-line path extending from a midpoint of a first line between first antenna and the second antenna to the mobile station and a second line that is perpendicular to the first line at the midpoint based on the first reception time, the second reception time, and the phase difference between the first signal and the second signal;
• and
• determining a location of the mobile station based on the known location of the access point and the angle of the straight-line path.

A non-transitory processor-readable storage medium having stored thereon processor-executable software instructions configured to cause a processor of a mobile station to perform operations comprising:

• receiving at a first reception time a first signal from a first antenna of the access point;
• receiving at a second reception time a second signal from a second antenna of the access point having a known distance from the first antenna;
• receiving at a third reception time a third signal from a third antenna of the access point having known distances from the first antenna and the second antenna;
• determining a first phase difference between the first signal and the second signal;
• determining a second phase difference between the first signal and the third signal;
• determining an angle of a straight-line path that extends from a midpoint of a centroid between the first antenna, the second antenna, and the third antenna to the mobile station and a perpendicular line that extends through the midpoint of the centroid based on the first reception time, the second reception time, the third reception time, the first phase difference between the first signal and the second signal, and the second phase difference between the first signal and the third signal;
• and
• determining a location of the mobile station based on the known location of the access point and the angle of the straight-line path from the perpendicular line that is parallel to at least one of the first antenna, the second antenna, and the third antenna and extends through a midpoint of the centroid between the first antenna, the second antenna, and the third antenna to the mobile station.

A mobile station, comprising:

• means for receiving at a first reception time a first signal from a first antenna of the access point;
• means for receiving at a second reception time a second signal from a second antenna of the access point having a known distance from the first antenna;
• means for determining a phase difference between the first signal and the second signal;
• means for determining an angle of a straight-line path extending from a midpoint of a first line between first antenna and the second antenna to the mobile station and a second line that is perpendicular to the first line at the midpoint based on the first reception time, the second reception time, and the phase difference between the first signal and the second signal;
• and
• means for determining a location of the mobile station based on the known location of the access point and the angle of the straight-line path.

A mobile station, comprising:

• means for receiving at a first reception time a first signal from a first antenna of the access point;
• means for receiving at a second reception time a second signal from a second antenna of the access point having a known distance from the first antenna;
• means for receiving at a third reception time a third signal from a third antenna of the access point having known distances from the first antenna and the second antenna;
• means for determining a first phase difference between the first signal and the second signal;
• means for determining a second phase difference between the first signal and the third signal;
• means for determining an angle of a straight-line path that extends from a midpoint of a centroid between the first antenna, the second antenna, and the third antenna to the mobile station and a perpendicular line that extends through the midpoint of the centroid based on the first reception time, the second reception time, the third reception time, the first phase difference between the first signal and the second signal, and the second phase difference between the first signal and the third signal;
• and
• means for determining a location of the mobile station based on the known location of the access point and the angle of the straight-line path from the perpendicular line that is parallel to at least one of the first antenna, the second antenna, and the third antenna and extends through a midpoint of the centroid between the first antenna, the second antenna, and the third antenna to the mobile station.