Patent ReferencesDigital compressive receiver Noiselike amplitude and phase modulation coding for spread spectrum transmissions Spread spectrum FH-MFSK radio receiver Adaptive spread spectrum FH-MFSK transmitter and receiver Spread spectrum FH-MFSK transmitter and receiver Multiple mixer spread spectrum modulation and method therefor Method and apparatus for data transmission using chirped frequency-shift-keying modulation Synchronizing system Synchronization system for use in direct sequence spread spectrum signal receiver Patent #: 4567588 InventorsAssigneeApplicationNo. 06/632001 filed on 07/18/1984US Classes:380/32, Wobbling of carrier375/149, Having specific code synchronization375/151, Having SAW or charge-transfer device375/354, SYNCHRONIZERS375/367, Pseudo noise380/35, Variable time delay modulation380/44Having particular key generatorExaminersPrimary: Cangialosi, SalvatoreAttorney, Agent or FirmInternational ClassH04B 1/707 (20060101)AbstractA system and method are disclosed for synchronizning the linear PN sequences contained in a received spread spectrum signal, characterized by the provision of a resident PN generator that is responsive to the chip rate clock for producing a replica of the PN sequence with arbitrary phase, a running matrix inverse of the matrix (R) formed by n successive observations of the register of the resident generator, and a matrix vector product device for multiplying the running inverse by a column vector of noisy chips, thereby to obtain a plurality of estimates of the phase vector. These estimates are smoothed and averaged to produce the smoothed phase vector (cj) that is applied to one input of a dot product device that operates in conjunction with the contents of the shift register of the resident generator to produce the properly phased PN sequence, which sequence is then supplied to despreading means for combining the noisy chips with the properly phased PN sequence. The system may be used for range computation, if desired. | |