Abstract: A method and apparatus are described for the unwrapping of a set of phase values observed for an incoming signal on a phased array antenna. The difference between values observed on adjacent elements in the array forms a first data set. The differences between adjacent ordinates in the first data set forms a second data set. The values in the second data set are rounded to the nearest whole multiple of one complete cycle before the differencing process is reversed to provide the values (representing a whole number of complete cycles) which are added to the observed phase values to provide the unwrapped phase values.

Abstract: To cater for the positioning of an aircraft in a boundary zone between two adjacent multilateration systems, the controller (14) in one system receives Time Difference of Arrival data provided by the controller (15) in the second system. The controller (15) derives the TDoA data from time of arrival data provided by its receiver stations (9-13). By furnishing TDoA data the timings of the two systems do not need to be synchronised. The controller (14) uses the TDoA data and also time of arrival data from its local receiver stations (4-8) to perform a multilateration to determine the location of the aircraft (16).

Abstract: A method and apparatus are described for the unwrapping of a set of phase values observed for an incoming signal on a phased array antenna. The difference between values observed on adjacent elements in the array forms a first data set. The differences between adjacent ordinates in the first data set forms a second data set. The values in the second data set are rounded to the nearest whole multiple of one complete cycle before the differencing process is reversed to provide the values (representing a whole number of complete cycles) which are added to the observed phase values to provide the unwrapped phase values.

Abstract: An automobile radar which serves to provide data for cruise control or other systems in a host vehicle, comprising means for measuring radar boresight misalignment by detecting the presence of apparent variations in the spacing of stationary objects from the direction of motion of the host vehicle and utilizing such detection to compensate for any misalignment.

Abstract: An automobile radar which serves to provide data for cruise control or other systems in a host vehicle, comprising means for measuring radar boresight misalignment by detecting the presence of apparent variations in the spacing of stationary objects from the direction of motion of the host vehicle and utilising such detection to compensate for any misalignment.