Abstract: An improved method for measuring the shape of a workpiece, and an associated device. The invention has three aspects. The first aspect of the invention is a triangulation device that creates an annular image whose diameter is a linear function of the distance from the device to the workpiece. According to the second aspect of the invention, the shape of a concave or reentrant workpiece is measured by folding the path of the incident light using a reflector inserted into the workpiece, so that light is reflected from the otherwise inaccessible interior walls of the workpiece. According to the third aspect of the invention, the incident beam of light is provided with a structured cross section.

Abstract: A system and method for operating a cellular communication system is disclosed wherein frequency reuse of available carrier frequencies is maximized, thereby maximizing system traffic capacity. The invention includes an outer cell grid generated by a plurality of base station transceivers connected to a common network controller. Within the grid of outer cells is at least one overlapping sub-grid of inner cells that may be generated by the same base stations as the outer cells, or which may be generated using separate base station transceivers located within the outer cell. At least two frequency reuse patterns are applied to the cells, one pattern for the outer cells and another, tighter pattern for the inner cells. The inner cells are defined and limited by a predetermined threshold co-channel interference level (C/I), the interference emanating from adjacent inner cells operating at the same frequencies.

Abstract: A joint signal detection and channel parameter estimation scheme is provided for multiple subcarrier signaling with pilot symbol-assisted modulation schemes. Known symbols located in the subcarriers are used to estimate a pair of parameters associated with the generation process of the fading frequency selectivity common to all of the subcarriers. These known symbol estimates are used to derive parameter pair estimates for unknown symbols located in the subcarriers. This parameter estimation thus effectively extracts information regarding the fading frequency selectivity through the pilot symbols received not only by the subcarrier of interest but by other subcarriers as well. The fading complex envelope with each subcarrier is then derived from the estimates of the parameter pair.

Abstract: An up-link channel assignment scheme for cellular mobile communications systems employing multibeam antennas with beam selection, in which a channel that is selected from among all variable channels in the same frequency band may be assigned to each of the antenna beams in a base station for communications. Channel selection for a base station takes place independently of that for other cells, such that the process is autonomous. Channel selection is based upon an estimate of the signal-to-interference power ration ("SIR") in which a channel having the smallest SIR estimate that is larger than or equal to a given threshold value is chosen. Alternatively, a channel having the largest SIR estimate is selected.