Abstract: This invention discloses a tracking and positioning system including a plurality of transmitters distributed within a working space, and at least one sensors attached to at least one moving object and operative to sense transmissions arriving from the plurality of transmitters, a dynamic transmission activator operative to track at least one position parameters of at least one of said sensors and to selectively activate and deactivate individual sets of at least one transmitters from among the plurality of transmitters, at least partly responsively to at leas one position parameters of at least one of the sensors. A tracking method for tracking a moving object whose initial position is substantially unknown is also disclosed.

Abstract: This invention discloses a pose tracking apparatus operative to track the pose of a moving object based on magnetic flux measurements taken in the vicinity of the moving object. The pose tracking apparatus includes a non-linear Kalman filter-based tracker. The tracker is operated to receive magnetic flux measurements performed in the vicinity of the moving object, and to operate a non-linear Kalman-type filter on said measurements, thereby to generate information regarding the pose of the moving object. In addition, the pose tracking apparatus includes a pose indicator operative to provide an output indication of the information regarding the pose of the moving object.

Abstract: A system for monitoring of the position of at least one portion of an object. The system includes a plurality of transmitters operative to transmit alternating magnetic fields within a three-dimensional space, and at least one positioning sensor arranged to be fixed to at least one corresponding portion of the object whose position it is sought to monitor. Each of the positioning sensors includes a magnetic field receiver having at least one active axis and operative to receive at least one component, lying along the at least one active axes respectively, of the alternating magnetic fields.

Abstract: A method of tracking an object within a surveillance area having a predetermined linear extent. One or more ultrasound transducers are fixed to the object. A plurality of background units are placed at known positions in the area, each unit including an ultrasound transducer. One or more ultrasound waves are transmitted between the object and the plurality of background units. The ultrasound waves are received if they have propagated between the object and the background units within a time window of a duration such that the product of the duration and the speed of sound is substantially less than the linear extent of the detection area. A characteristic of the received ultrasound waves is determined, and coordinates of the object are determined responsive to the characteristic.

Abstract: A new method to fabricate strain patterns on a strained semiconductor structure, is disclosed. The method is based on the new concept of reverse side etching of a laterally homogeneous, strained structure so that strain changes can be induced in the front-side, pre-strained area as a result of the reverse side etching process. Semiconductor structures such as quantum-wires, quantum dots, and quantum well devices may be formed by the disclosed methods where the reverse side etching provides strain control of the material properties of the semiconductor structure without processing the front side which is generally the active and the most sensitive region of the semiconductor structure. Such semiconductor structures can be formed by a process including the steps of forming a strained layer on the front-side of the structure, and etching the reverse side of the substrate to form a pattern of strain into the front-side, thus forming selectively strained regions.