System and method for locating a point in space

摘要

A method for locating a point in a first region based on receipt of a rf signal from the point. An antenna array is in the first region at a first position rotatable about an axis. A series of phase-array patterns is provided for implementation with the antenna array to provide measures of rf signal strength. Each pattern provides a plurality of reference values as a function of angle. A plurality of the phase-array patterns are used to acquire, in the first region, a plurality of rf signal strength values based on reception of the rf signal. A set of correlation values is determined where each value is a correlation between signal strength reference values and rf signal strength values acquired based on reception of the rf signal from the point. The correlation values identify a direction relative to the first position along which the point is located.

主权项

1. A method for locating a point about a first axis in a first region based on receipt of a radio frequency (rf) signal that emanates from the point, comprising:
providing an antenna array; providing a series of phase-array patterns for receiving measures of rf signal strength with the antenna array, each pattern characterized varied signal strength responses to the rf signal as a function of angle of pattern rotation, the series comprising a set of patterns each including a null region; using the antenna array with each phase-array pattern to provide signal strength reference values as a function of pattern angle of rotation; with the antenna array at the first position, further using the set of phase-array patterns to acquire signal strength responses to the rf signal that emanates from the point as a function of angle of pattern rotation about the first axis wherein, for each in the set of patterns (i) a roll-off in signal strength responses is characteristic of portions of null regions oriented in pointing directions toward the source, and (ii) a portion of each null region exhibits a measurably different change in signal strength response, as a function of pattern angle about the first axis, relative to other changes in signal strength responses as a function of pattern angle about the first axis for other portions of the pattern; determining a set of correlation values based on correlations between (i) signal strength reference values acquired with patterns at angles of rotation and (ii) the signal strength responses acquired with the antenna array based on reception of the rf signal that emanates from the point; and using the correlation values to identify a direction relative to the first position along which the point is located.