EP0236017A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Synchronizing signal decoding
Assignee: Sony Corp
•
Filing: 1987-02-19
•
Granted: —
•
Expires: 2007-02-19
Abstract
Abstract A method of decoding digital synchronizing signals each of which consists of a plurality of bits in a predetermined pattern, the intervals between the starts of succesive synchronizing signals in an input digital signal being variable over a range, comprises ascertaining the bit period distance between the starts of two successive synchronizing signals, subsequently searching the input digital signal for the pattern using a window comprising the bit period distance, which window is varied in position if the bit period distance changes, and supplying an output synchronizing pulse in synchronism with subsequent synchronizing signals found in the window.
Inventors
- 👤 James Hedley Wilkinson
- 👤 Roger Lagadec
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 15:56
CPC Classifications
G; G11; G11B; G11B27/00; G11B27/10; G11B27/19; G11B27/28; G11B27/30; G11B27/3027; G11B20/00; G11B20/10; G11B20/12; G11B20/1262; G11B20/14; G11B20/1403; H; H04; H04L; H04L7/00; H04L7/0016; H04L7/0033; H04L7/0037; H04L7/04; H04L7/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
114 words
A method of decoding digital synchronizing signals each of which consists of a plurality of bits in a fixed pattern; characterised in that: the intervals between the starts of successive said synchronizing signals in an input digital signal are variable over a range of P plus or minus Q bit periods; the method comprising: ascertaining the bit period distance between the starts of two successive said synchronizing signals; subsequently searching said input digital signal for said pattern using a window comprising said bit period distance, which window is varied in position if said bit period distance changes; and supplying an output synchronizing pulse in synchronism with subsequent said synchronizing signals found in said window.
Claim 2
Independent Claim
114 words
A method of decoding digital synchronizing signals each of which consists of a plurality of bits in a fixed pattern; characterised in that: the intervals between the starts of successive said synchronizing signals in an input digital signal are variable over a range of P plus or minus Q bit periods; the method comprising: ascertaining the bit period distance between the starts of two successive said synchronizing signals; subsequently searching said input digital signal for said pattern using a window comprising said bit period distance, which window is varied in position if said bit period distance changes; and supplying an output synchronizing pulse in synchronism with subsequent said synchronizing signals found in said window.
Claim 3
Dependent Claim
25 words
A method according to claim 1 wherein said bit period distance is ascertained by first searching said input digital signal for two successive said patterns.
Claim 4
Dependent Claim
22 words
A method according to claim 2 wherein said first search uses a window extending from P-Q bit periods to P+Q bit periods.
Claim 5
Dependent Claim
30 words
A method according to claim 1, claim 2 or claim 3 wherein said subsequent search uses a window extending one bit period on each side of said bit period distance.
Claim 6
Independent Claim
29 words
A method according to any one of the preceding claims wherein said input digital signal comprises channel status information bits or user bits in a digital audio data signal.
Claim 7
Dependent Claim
115 words
Apparatus for decoding digital synchronizing signals each of which consists of a plurality of bits in a fixed pattern; characterised in that: the intervals between the starts of successive said synchronizing signals in an input digital signal are variable over a range of P plus or minus Q bit periods; the apparatus comprising: means for ascertaining the bit period distance between the starts of two successive said synchronizing signals; means for subsequently searching said input digital signal for said pattern using a window comprising said bit period distance, which window is varied in position if said bit period distance changes; and means for supplying an output synchronizing pulse in synchronism with subsequent said synchronizing signals.
Claim 8
Dependent Claim
115 words
Apparatus for decoding digital synchronizing signals each of which consists of a plurality of bits in a fixed pattern; characterised in that: the intervals between the starts of successive said synchronizing signals in an input digital signal are variable over a range of P plus or minus Q bit periods; the apparatus comprising: means for ascertaining the bit period distance between the starts of two successive said synchronizing signals; means for subsequently searching said input digital signal for said pattern using a window comprising said bit period distance, which window is varied in position if said bit period distance changes; and means for supplying an output synchronizing pulse in synchronism with subsequent said synchronizing signals.
Claim 9
Dependent Claim
26 words
Apparatus according to claim 6 further comprising means for ascertaining said bit period distance by first searching said input digital signal for two successive said patterns.
Claim 10
Dependent Claim
27 words
Apparatus according to claim 6 or claim 7 wherein said subsequent search uses a window extending one bit period on each side of said bit period distance.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.