Abstract: A mobile device determines its location accurately by measuring the range to a position reflector as well as azimuth and elevation angles of arrival (AOA) at the reflector. The mobile can transmit a coded radar signal and process reflections to determine its location. The reflectors may include internal delays that can identify the reflector and provide transmit/receive separation for the mobile. The reflection can include a primary and further delayed secondary reflection. The mobile can determine the internal delay of the reflector based on the delay between primary and secondary reflections. The range and AOA information can be combined with information about the position, orientation, and characteristics of the reflectors to determine location. In some systems, the mobile device can determine its location in a three-dimensional space using reflections from only one reflector. The reflectors, which can be economically produced, can be unpowered and low profile for easy installation.

Abstract: An irrigation system continuously monitors status of lawns or plants under its care and directs water to where it is needed when it is needed to maintain lawn or plant health. The system can significantly reduce water usage, unnecessary seepage, and runoff. A water nozzle with a pan and tilt capability can direct water where it is needed. An image sensor can continually take and analyze images of the lawns or plants to determine watering needs. The image sensor can also monitor where the water is landing while the irrigation system is delivering water to the lawns or plants. This information can be used to adjust the water delivery aim to ensure that the intended spots are accurately irrigated. A laminar flow nozzle with minimal flow dispersion can improve water deliver accuracy and detection of where the water lands.