Synchronization of modules in a wireless array

• US 8,228,757 B2
• Filed: 12/31/2009
• Issued: 07/24/2012
• Est. Priority Date: 12/31/2009
• Status: Active Grant

• Current Assignee: Wireless Seismic Incorporated
• Original Assignee: Wireless Seismic Incorporated
• Inventors: Beffa, Mihai, Day, Calvin, Rose, Kevin, Kooper, Steven, Elder, Keith
• Primary Examiner(s): Hellner, Mark
• Application Number:
  US12/651,091
• Publication Number:
  US 20110158047A1
• Time in Patent Office: 936 Days
• Field of Search: 367/40, 367/50, 367/55, 367/76, 367/79, 702/17
• US Class Current: 367/50
• CPC Class Codes: G01V 1/223 Radioseismic systems

Abstract

Presented are systems and methods for wireless data acquisition. The wireless data acquisition may involve synchronizing modules within a data acquisition array. The synchronized data acquisition array may be used to facilitate a seismic survey. Synchronization may be facilitated by receipt of a reference time event such that a clock is synchronized based on the reference time event.

Claims

1. A method for synchronizing a wireless data acquisition module in a seismic array, the method comprising:

first receiving at the wireless data acquisition module a time reference event from a separate first component of said seismic array;

determining a delay value associated with said received time reference event, wherein the delay value includes a transmission delay associated with transmission of the time reference event from the first component to the wireless data acquisition module; and

adjusting a clock based on the delay value to synchronize the clock in relation to the time reference event.

2. The method of claim 1, wherein the delay value includes a hardware processing delay for the time reference event.

3. The method of claim 1, wherein the reference time event includes clock data from the first component.

4. The method of claim 3, wherein the clock data includes information about a second module clock located remotely from the seismic data acquisition module.

5. The method of claim 3, wherein the reference time event includes source data independent of said clock data, regarding said first component.

6. The method of claim 5, wherein the source data includes location information about a source of the time reference event located remotely from the seismic data acquisition module by a distance.

7. The method of claim 6, wherein the source data is used in the calculation to determine the delay value at least partially based on the distance.

8. The method of claim 1, further comprising:

generating the reference time event from a known time value.

9. The method of claim 8, wherein the known time value is GPS time.

10. The method of claim 1, further comprising:

generating a second time reference event; and

transmitting the second time reference event.

11. The method of claim 1, further comprising:

second receiving, at said wireless data acquisition module, seismic data from an upstream module at a first time; and

transmitting, from said wireless data acquisition module, the seismic data to a downstream module at a second time;

wherein the transmitting and second receiving is coordinated using the clock.

12. The method of claim 1, wherein the adjusting includes changing a frequency of the clock.

13. The method of claim 1, wherein the adjusting includes determining a compensation value to compensate for a time period occurring prior to the adjusting in which the clock was out of synchronization.

14. The method of claim 13, wherein the compensation value is at least partially determined by integrating a frequency differential over the time period.

15. The method of claim 1, wherein the adjusting includes at least one of advancing and regressing the phase of the clock.

16. A method for synchronizing wireless modules used for data delivery in a seismic data acquisition system, the method comprising:

providing an array comprising a plurality of seismic data acquisition modules that establish a serial data transfer path;

receiving synchronization metadata at one module from at least one other module of the plurality of seismic data acquisition modules;

synchronizing a clock of the one module using the synchronization metadata;

establishing a timed delivery protocol between the plurality of seismic data acquisition modules implemented based on the synchronized clocks, wherein the timed delivery protocol includes time division multiplexed data transmission, and wherein the time division multiplexed data transmission is controlled at least partially by the clock.

17. The method for synchronization of claim 16, wherein the at least one other module is a base station.