Abstract: A Direct Sequence Spread Spectrum receiver is described in which a complex spread spectrum signal is cross correlated by four digitally matched filters. The filters and subsequent multipliers correlate the in-phase and quadrature components as well as the current and previous symbols. The result is a more robust signal acquisition at very low signal to noise ratios.

Abstract: A gas collector is disclosed for use with epitaxial reactors. The gas collector is in the form of a base and top portion that are interconnected by means of a sealing arrangement. The top portion is configured to cover the base and define a conduit therebetween. Inlets and outlets are provided to direct chemical vapors from a reaction chamber of the epitaxial reactor into the conduit and further into an exhaust pipe of the epitaxial reactor. The gas collector is capable of forming a hermetic seal with the lid of the reaction chamber in order to prevent escape of chemical vapors.