Signal degradation detection

• US 8,824,989 B2
• Filed: 12/21/2012
• Issued: 09/02/2014
• Est. Priority Date: 06/25/2010
• Status: Active Grant

• Current Assignee: Dish Technologies LLC (Dish Network Corporation)
• Original Assignee: Echostar Technologies LLC (Echostar Corporation)
• Inventors: Jackson, Robert J.V., Zhang, Tianhua, Elkaissi, Moutaz, Nguyen, Hao, Sotelo, Jorge, Blackman, Wendell, Goldey, Greg
• Primary Examiner(s): PHU, SANH D
• Application Number:
  US13/725,295
• Publication Number:
  US 20130109336A1
• Time in Patent Office: 620 Days
• Field of Search: 455/226.1, 455/427, 455/437, 455/552.1, 455/456.1, 455/456.2
• US Class Current: 455/226.1
• CPC Class Codes: H04B 17/373 Predicting channel quality or other radio frequency [RF] parameters
• CPC Class Codes: H04L 41/147 for predicting network behaviour
• CPC Class Codes: H04L 41/149 for prediction of maintenance
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04N 17/004 for digital television systems
• CPC Class Codes: H04N 21/25808 Management of client data terminal profiles in network data switching protocols H04L67/303
• CPC Class Codes: H04N 21/44209 Monitoring of downstream path of the transmission network originating from a server, e.g. bandwidth variations of a wireless network arrangements for maintenance or administration in data switching networks involving bandwidth and capacity management H04L41/0896
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6582 Data stored in the client, e.g. viewing habits, hardware capabilities, credit card number arrangements where receivers interact with the broadcast H04H20/38

Abstract

Implementations are directed to predicting signal degradation at receivers used to display a programming service. The receivers capture signal strength data that is then transmitted to a processing location, which may be associated with a provider of the programming service. A signal degradation detector at the provider operates to predict whether or not a future unacceptable signal quality will occur within a time interval. The prediction may be based on a test quantity calculated from signals captured at the receiver and based on a figure of merit for the geographic locale in which the receiver is located. A maintenance call may be initiated for those receivers that have such a poor signal quality.

Claims

1. A method to predict a maintenance condition of a receiver, comprising:

determining a time series of test quantities for the receiver, the test quantities based on signal strength measurements collected at the receiver at a plurality of time instances;

receiving a figure of merit for the receiver, the figure of merit indicating an expected signal quality for the receiver;

eliminating the receiver as a candidate for failure prediction if the time series of test quantities is equal or greater than the figure of merit for a predetermined period of time;

determining a failure prediction for the receiver based on the time series of test quantities and the figure of merit, the act of determining the failure prediction only performed if the receiver is not eliminated as a candidate for failure prediction; and

identifying the receiver if the failure prediction indicates a future unacceptable signal strength for the receiver.

2. The method of claim 1, further comprising:

eliminating the receiver as a candidate for failure prediction if the time series of test quantities trends level or trends upward for a predetermined number of time instances.

3. The method of claim 1, further comprising:

applying recursive linear regression to the time series of test quantities and the figure of merit to produce a linear function, wherein the linear function is used to determine the failure prediction for the receiver; and

rejecting a particular test quantity from the recursive linear regression if the particular test quantity indicates a transient condition.

4. The method of claim 3, further comprising:

calculating a first error for the linear function based on a particular test condition, the first error corresponding to a predicted signal strength for a first time instance subsequent to a time instance of the particular test quantity;

if the first error is greater than a predetermined error threshold, calculating a second error for the linear function based on the particular test condition, the second error corresponding to a predicted signal strength for a second time instance subsequent to the time instance of the particular test quantity; and

if the second error is less than a predetermined error threshold, determining that the particular test quantity indicates a transient condition.

5. The method of claim 1 wherein the figure of merit indicates an expected signal quality for receivers in a geographic region in which the receiver is located.

6. A method to predict a maintenance condition of a receiver, comprising:

storing a time series of test quantities for the receiver, the test quantities based on signal strength measurements collected at the receiver at a plurality of time instances;

storing a figure of merit for the receiver, the figure of merit indicating an acceptable signal quality for the receiver;

eliminating the receiver as a candidate for failure prediction if the time series of test quantities trends level or trends upward for a predetermined number of time instances;

producing a failure prediction for the receiver based on the time series of test quantities and the figure of merit, the act of producing the failure prediction conditionally performed if the receiver is not eliminated as a candidate for failure prediction; and

identifying the receiver if the failure prediction indicates a future unacceptable signal strength for the receiver.

7. The method of claim 6, further comprising:

eliminating the receiver as a candidate for failure prediction if the time series of test quantities is equal or greater than the figure of merit for a predetermined period of time.

8. The method of claim 6, further comprising:

computing a linear function with a recursive linear regression algorithm applied to the time series of test quantities and the figure of merit, the linear function used to produce the failure prediction for the receiver; and

rejecting a particular test quantity from the recursive linear regression if the particular test quantity indicates a transient condition.

9. The method of claim 6 wherein the figure of merit indicates an acceptable signal quality for receivers during a fixed time interval.

10. The method of claim 6 wherein the figure of merit indicates an acceptable signal quality for receivers in a geographic region in which the receiver is located.

11. A system to provide maintenance to a receiver, comprising:

a memory module configured to store a time series of test quantities for a receiver and a figure of merit for the receiver, the time series of test quantities derived from signal strength measurements collected over time at the receiver and the figure of merit corresponding to an acceptable signal quality for the receiver; and

a prediction module configured to;

remove the receiver as a candidate for maintenance if the time series of test quantities is acceptable relative to the figure of merit for a predetermined period of time; and

predict a maintenance condition for the receiver based on the time series of test quantities and the figure of merit, the act of predicting the maintenance condition only performed if the receiver is not removed as a candidate for maintenance.

12. The system of claim 11 wherein the prediction module is further configured to:

remove the receiver as a candidate for maintenance if the time series of test quantities trends level or trends toward a more acceptable value for a predetermined number of time instances.

13. The system of claim 11 wherein the prediction module is further operable to:

apply recursive linear regression to the time series of test quantities to compute a linear function from the time series of test quantities; and

reject a particular test quantity from the linear regression if the particular test quantity is indicative of a transient condition.

14. The system of claim 13 wherein the prediction module is further operable to:

calculate a first error for the linear function based on a particular test condition, the first error corresponding to a predicted signal strength for a first time instance subsequent to a time instance of the particular test quantity;

if the first error is greater than a predetermined error threshold, calculate a second error for the linear function based on the particular test condition, the second error corresponding to a predicted signal strength for a second time instance subsequent to the time instance of the particular test quantity; and

if the second error is less than a predetermined error threshold, determine that the particular test quantity is indicative of a transient condition.

15. The system of claim 11 wherein a receiver is removed as a candidate for maintenance for a fixed time interval.

16. A system to provide maintenance to a receiver, comprising:

a memory module configured to store a time series of test quantities for a receiver and a figure of merit for the receiver, the time series of test quantities derived from signal quality measurements collected over time at the receiver and the figure of merit corresponding to an expected signal quality for the receiver; and

a prediction module configured to perform at least one of;

removing the receiver as a candidate for maintenance if the time series of test quantities trends level or trends toward a more acceptable value for a predetermined number of time instances; and

removing the receiver as a candidate for maintenance if the time series of test quantities is acceptable relative to the figure of merit for a predetermined period of time;

wherein the prediction module is further configured to predict a maintenance condition for the receiver based on the time series of test quantities and the figure of merit, the act of predicting the maintenance condition only performed if the receiver is not removed as a candidate for maintenance.

17. The system of claim 16 wherein each signal quality measurement is representative of signal strength taken at the receiver.

18. The system of claim 16 wherein the prediction module is further operable to:

apply recursive linear regression to the time series of test quantities to compute a linear function from the time series of test quantities; and

reject a particular test quantity from the linear regression if the particular test quantity is indicative of a transient condition.

19. The system of claim 18 wherein the prediction module is further operable to:

calculate a first error for the linear function based on a particular test condition, the first error corresponding to a predicted signal strength for a first time instance subsequent to a time instance of the particular test quantity;

if the first error is greater than a predetermined error threshold, calculate a second error for the linear function based on the particular test condition, the second error corresponding to a predicted signal strength for a second time instance subsequent to the time instance of the particular test quantity; and

if the second error is less than a predetermined error threshold, determine that the particular test quantity is indicative of a transient condition.

20. The system of claim 16 wherein a receiver is removed as a candidate for maintenance for a fixed time interval.