SR Technologies, Inc.

A method, wireless device and measuring station are disclosed that determine the best fit geo-location of a target station. According to one aspect, a method includes, using a “Pass Filter” for minimization of the summation of squared miss probabilities SSMP that improves the fitting process of the measured data over the method of minimization of the summation of the squared residuals (SSR) in the presence of spurious measurements. A “Pass Filter” approach is disclosed that reduces the corruption of the fitting process by outlier data and still yields the same result in the limit of clean data as the classic summation of the squared residuals (SSR) method.

A method for determining reception window timing using a measuring station receiving an antenna beam width, receiving an antenna tilt angle, receiving an altitude A, determining a far projection angle Δf, determining a near projection angle Δn, and determining a far projection range corresponding to the far projection angle Δf and based at least upon the values of Δf and A. The method further includes determining a near projection range corresponding to the near projection angle Δn and based at least upon the values of Δn and A, determining an end time of a reception window based at least upon the value of the far projection range the reception window being a window of time in which a response from the target station is expected to be received, and determining a start time of the reception window based at least upon the value of the near projection range

A method and devices are disclosed that increase the range of active geo-location from the airborne measuring station as compared with known methods by increasing the effective receive sensitivity of the airborne measuring station. In one embodiment this may be accomplished by transmitting a predetermined ranging packet and correlating the raw received bit stream of the response packet with the predetermined bit stream. In one embodiment, the disclosed method applies to the reception of IEEE 802.11 direct sequence spread spectrum DSSS ACK and DSSS CTS packets in response to DSSS data null and DSSS RTS packets respectively, in the 2.4 GHz band.