Communication over noisy lines
Patent 4517679 Issued on May 14, 1985. Estimated Expiration Date: 
March 7, 2003. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 7, 2003. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3878527 Telemetry Synchronizer Spread spectrum demodulator Communication Coherent spread spectrum receiving apparatus Patent #: 4435822 InventorsAssigneeApplicationNo. 06/473055 filed on 03/07/1983US Classes:375/259, SYSTEMS USING ALTERNATING OR PULSATING CURRENT375/343, Correlative or matched filter375/367Pseudo noiseExaminersPrimary: Griffin, Robert L.Assistant: Chin, Stephen Attorney, Agent or FirmInternational ClassesH04L 23/00 (20060101)H04B 1/707 (20060101) H04L 23/02 (20060101) Foreign Application Priority Data1982-03-10 GBAbstractIn a line network communication system coded data signals are transmitted on a base band carrier signal and are recovered in a receiver. The receiver includes an exclusive OR gate and a shift register which operate in conjunction to compare, during successive time intervals, a series of coded reference signals and a succession of received signals shifted in phase relative to one another by respective amounts to generate respective comparison signals forming a set. A control unit causes a change in the relative phases of compared signals until the value of a comparison signal in a set indicates a degree of correlation exceeding a threshold value. Then, in a tracking mode, the control unit monitors the values of comparison signals generated in successive sets to verify that a degree of correlation exceeding the threshold value persists. If the verification is successful the control unit, in a locking mode, adjusts the relative phases of the compared signals to maintain a desired degree of correlation. | |
