Arrangement to provide an accurate time-of-arrival indication for a received signal

• US 4,559,606 A
• Filed: 07/11/1983
• Issued: 12/17/1985
• Est. Priority Date: 07/11/1983
• Status: Expired due to Term

• Current Assignee: ITT Corporation (ITT, Inc.)
• Original Assignee: International Telephone & Telegraph Corp. (ITT, Inc.)
• Inventors: Lu, Ning H., Jezo, Maurice L.
• Primary Examiner(s): Malzahn, David H.
• Application Number:
  US06/512,280
• Time in Patent Office: 890 Days
• Field of Search: 364/728, 364/819, 364/715, 364/569
• US Class Current: 708/425
• CPC Class Codes: G01S 11/08 using synchronised clocks
• CPC Class Codes: H04B 1/707 using direct sequence modulation

Abstract

The arrangement comprises a plurality of correlation means coupled to the received signal with the received signal being clocked into each of the plurality of correlation means by a different one of a plurality of different phased clocks with the different phased clocks occurring at a predetermined different time uniformly spaced over a given time interval and integration means coupled to each of the plurality of correlation means to provide the indication of the time of arrival of the received signals. The plurality of correlation means includes a plurality of shift registers into which the received signals are shifted by a different one of the plurality of phased clocks, a reference signal register and a plurality of comparison means each coupled to each stage of a different one of the plurality of shift registers and each stage of the common reference signal shift register to compare the contents of the associated stages of the plurality of signal shift registers and the single common reference signal shift register and to produce an output signal indicative of the results of each of the comparisons.

Claims

1. An arrangement to provide an accurate time-of-arrival indication for a received signal comprising:

N correlation means coupled to said received signal, where N is an integer greater than one, said received signal being clocked into each of said N correlation means by a different one of N-phase clocks, said N-phase clocks occurring at a predetermined different time uniformly spaced over a given time interval; and

integration means coupled to each of said N correlation means to provide said indication of said time-of-arrival of said received signal.

2. An arrangement according to claim 1, wherein

said N correlation means includes

N shift registers coupled to said received signal, said received signal being shifted into each of said N shift registers by said different one of said N-phase clocks,

a reference signal shift register, and

N comparison means each coupled to each stage of a different one of said N shift registers and each stage of said reference signal shift register to compare the contents of associated stages of said different one of said N shift registers and said reference signal shift register and produce an output signal indicative of the results of each of said comparisons.

3. An arrangement according to claim 2, wherein

each of said N comparison means includes

a plurality of EXCLUSIVE-OR gates each coupled to a different associated stage of said different one of said N shift registers and said reference signal shift register to produce said output signal indicative of the result of said comparison.

4. An arrangement according to claim 3, wherein

said integration means includes a summing network coupled to each of said plurality of EXCLUSIVE-OR gates to sum said output signals to provide said indication of said time-of-arrival of said received signal.

5. An arrangement according to claim 2, wherein

said integration means includes a summing network coupled to said N comparison means to sum said output signals to provide said indication of said time-of-arrival of said received signal.

6. An arrangement according to claim 1, wherein

said integration means includes a summing network coupled to said N correlation means to sum output signals therefrom to provide said indication of said time-of-arrival of said received signal.