Patent ID: 6400754
Filing Date: 2002-06-04
Classification: G01S,H04B

Abstract:
A timebase of a spread spectrum transceiver providing a first communication triggering signal having a beginning communication time, comprising:a low-frequency clock signal source providing a low-frequency clock signal having a sequence of low-frequency clock pulses; a low-noise phase-lock loop for generating a high-frequency clock signal from said low-frequency clock signal; a stage-one low-noise counter maintaining a first count of clock impulses of said high-frequency clock signal; a stage-one event register for storing a high-frequency portion of said beginning communication time; a stage-one low-noise comparator for providing said first communication triggering signal when said first high-frequency portion of said beginning communication time is equal to said first count; a stage-one low-noise switching means for activating said stage-one low-noise counter, and stage-one low-noise reception comparator when a stage-one enable signal is received; and a stage-two low-noise counter for maintaining a second count of said low-frequency clock pulses when active; a stage-two standard-circuitry counter for maintaining a third count of said low-frequency clock pulses when active; a stage-two event register for storing an intermediate-frequency portion of said beginning communication time; a stage-two low-noise comparator for sending said stage-one enable signal to said stage-one low-noise switching means when said intermediate-frequency portion of said beginning communication time corresponds to said second count; a stage-two switching means for activating said stage-two low-noise counter and said stage-two low-noise comparator, and inactivating said stage-two standard-circuitry counter, after a stage-two enable signal is received; and a stage-three standard-circuitry counter for maintaining a fourth count of terminal counts from said stage-two low-noise counter and said stage-two standard-circuitry counter; a stage-three event register for storing a reception low-frequency portion of said beginning communication time; and a stage-three standard-circuitry comparator for sending said stage-two enable signal to said stage-two reception switching means when said low-frequency portion of said beginning communication time corresponds to said fourth count.