Abstract: An apparatus for decoding a received spread spectrum signal having a data signal modulated with a pseudo-noise code and transmitted as an RF spread spectrum signal. A first reference register holds a first pseudo-noise signal, a second reference register holds a second pseudo-noise signal, and a receive-register holds a received spread spectrum signal. A first modulo adder adds each chip of the received spread spectrum signal with each respective chip of the first pseudo-noise signal, thereby generating a first plurality of chip-comparison signals. A first summer adds the first plurality of chip-comparison signals, generating a first correlation signal. The comparator compares the correlation signal to an upper-threshold level and a lower-threshold level, and respectively generates a first data-symbol signal or a second data-symbol signal.

Abstract: A surface-acoustic-wave correlator for decoding a spread-spectrum signal having a data signal modulated with a plurality of chip sequences and reciprocal-chip sequences. A tapped-delay-line has a plurality of taps defining a tapped-delay-line structure matched to the chip sequence. In response to a plurality of first chips and second chips embedded in the spread-spectrum signal, the tapped-delay line generates TDL-chip sequences and inverse-TDL-chip sequences. A first transducer is acoustically coupled to the tapped-delay-line. In response to the spread-spectrum signal modulated by the chip sequence, the first transducer correlates a first group of the plurality of TDL-chip sequences and inverse-TDL-chip sequences and outputs a first correlation pulse. A second transducer is acoustically coupled to the tapped-delay-line.

Abstract: An apparatus for decoding a received spread spectrum signal having a data signal modulated with a pseudo-noise code and transmitted as an RF spread spectrum signal. A reference-sequence-storage device holds a reference-pseudo-noise signal, and a receive-sequence storage device holds a received spread spectrum signal. A chip comparator adds each chip of the received spread spectrum signal by each respective chip of the pseudo-noise signal, thereby generating a plurality of chip comparison signals. A summer adds the plurality of chip comparison signals, generating a correlation signal. The comparator compares the correlation signal to a statistically predetermined threshold level, and generates a first data-symbol signal.