Methods and apparatus to scan a wireless communication spectrum
View Patent ↗Methods and apparatus are disclosed to scan a wireless communication spectrum. An example method disclosed herein includes causing a first scanner to determine, for a frequency of a wireless communication spectrum, a decoded base station identifier, causing a second scanner to determine a plurality of signal strengths at the frequency without determining a base station identifier, and determining that the base station identifier is associated with a subset of the plurality of signal strengths by comparing at least one of timestamps and locations associated with the base station identifier and the plurality of signal strengths.
1. A method comprising:
detecting with a first scanner scanning at a first rate a base station identifier for a frequency of a wireless communication spectrum;
detecting with a second scanner scanning at a second rate, different from the first rate, a plurality of signal strengths of signals at the frequency without determining a base station identifier; and
determining that the base station identifier is associated with a subset of the plurality of signal strengths by comparing at least one of times and physical locations at which the base station identifier and the plurality of signal strengths were detected.
2. A method as defined in claim 1 , wherein the first scanner and the second scanner are located in a scanner housing and implemented by first and second digital signal processors, respectively.
3. A method as defined in claim 1 , wherein the first and second scanners operate simultaneously.
4. A method as defined in claim 1 , wherein the first frequency corresponds to a channel of the wireless communication spectrum and the wireless communication spectrum is a global system for mobile communication (GSM).
5. A method as defined in claim 1 , further comprising timestamping the base station identifier and the plurality of signal strengths,
wherein determining that the base station identifier is associated with the subset of the plurality of signal strengths comprises determining a first timestamp associated with the base station identifier is within a time period of a second timestamp associated with one of the plurality of signal strengths in the subset.
6. A method as defined in claim 1 , further comprising determining a geolocation of the first scanner when the first scanner determines the base station identifier and a plurality of geolocations of the second scanner when the second scanner determines corresponding ones of the plurality of signal strengths,
wherein determining that the base station identifier is associated with the subset of the plurality of signal strengths comprises determining a first geolocation associated with the base station identifier is within a radius of corresponding ones of the plurality of geolocations.
7. A method as defined in claim 1 , further comprising timestamping the base station identifier and the plurality of signal strengths; and
determining a geolocation of the first scanner when the first scanner determines the base station identifier and a plurality of geolocations of the second scanner when the second scanner determines corresponding ones of the plurality of signal strengths,
wherein determining that the base station identifier is associated with the subset of the plurality of signal strengths comprises determining a first timestamp associated with the base station identifier is within a time period of a second timestamp associated with one of the plurality of signal strengths in the subset, and
wherein determining the base station identifier is associated with the subset of the plurality of signal strengths comprises determining a first geolocation associated with the base station identifier is within a radius of corresponding ones of the plurality of geolocations.
8. A method as defined in claim 1 , wherein, detecting with the first scanner determines a second plurality of signal strengths for the frequency.
9. A method as defined in claim 1 , wherein the second rate is faster than the first rate.
10. An apparatus comprising:
a first scanner to scan a frequency of a wireless communication spectrum at a first rate to identify a base station identifier;
a second scanner to scan the frequency at a second rate different from the first rate to determine a plurality of signal strengths; and
a correlator to determine that the base station identifier is associated with a subset of the plurality of signal strengths by comparing at least one of timestamps and physical locations of the first and second scanners when the base station identifier and the plurality of signal strengths were detected.
11. An apparatus as defined in claim 10 , wherein the first scanner and the second scanner are located in a scanner housing and implemented by a first and second digital signal processor, respectively.
12. An apparatus as defined in claim 10 , wherein the first and second scanners operate simultaneously.
13. An apparatus as defined in claim 10 , wherein the first frequency corresponds to a channel of the wireless communication spectrum and the wireless communication spectrum is a global system for mobile communication (GSM).
14. An apparatus as defined in claim 10 , further comprising a timestamper to timestamp the base station identifier and the plurality of signal strengths,
wherein the correlator is to determine that the base station identifier is associated with the subset of the plurality of signal strengths by determining a first timestamp associated with the base station identifier is within a time period of a second timestamp associated with one of the plurality of signal strengths in the subset.
15. A apparatus as defined in claim 10 , further comprising a geolocator to determine a geolocation of the first scanner when the first scanner determines the base station identifier and a plurality of geolocations of the second scanner when the second scanner determines corresponding ones of the plurality of signal strengths,
wherein the correlator is to determine that the base station identifier is associated with the subset of the plurality of signal strengths by determining a first geolocation associated with the base station identifier is within a radius of corresponding ones of the plurality of geolocations.
16. An apparatus as defined in claim 10 , further comprising a timestamper to timestamp the base station identifier and the plurality of signal strengths; and
a geolocator to determine a geolocation of the first scanner when the first scanner determines the base station identifier and a plurality of geolocations of the second scanner when the second scanner determines corresponding ones of the plurality of signal strengths,
wherein the correlator is to determine that the base station identifier is associated with the subset of the plurality of signal strengths by determining a first timestamp associated with the base station identifier is within a time period of a second timestamp associated with one of the plurality of signal strengths in the subset, and
wherein the correlator is to determine the base station identifier is associated with the subset of the plurality of signal strengths by determining a first geolocation associated with the base station identifier is within a radius of corresponding ones of the plurality of geolocations.
17. An apparatus as defined in claim 10 , wherein the first scanner is to detect a second plurality of signal strengths for the frequency.
18. An apparatus as defined in claim 10 , wherein the second rate is faster than the first rate.
19. A machine readable storage medium comprises instructions which, when executed, cause a machine to at least:
cause a first scanner scanning at a first rate to detect a base station identifier for a frequency of a wireless communication spectrum;
cause a second scanner scanning at a second rate, different from the first rate, to detect a plurality of signal strengths of signals at the frequency without determining a base station identifier; and
determine that the base station identifier is associated with a subset of the plurality of signal strengths by comparing at least one of times and physical locations at which the base station identifier and the plurality of signal strengths were detected.
20. A storage medium according to claim 19 , wherein the first scanner and the second scanner are located in a scanner housing and implemented by first and second digital signal processors, respectively.
21. A storage medium according to claim 19 , wherein first and second scanners operate simultaneously.
22. A storage medium according to claim 19 , wherein the first frequency corresponds to a channel of the wireless communication spectrum and the wireless communication spectrum is a global system for mobile communication (GSM).
23. A storage medium according to claim 19 , wherein the instructions cause the machine to timestamp the base station identifier and the plurality of signal strengths,
wherein the instructions cause the machine to determine that the base station identifier is associated with the subset of the plurality of signal strengths by determining a first timestamp associated with the base station identifier is within a time period of a second timestamp associated with one of the plurality of signal strengths in the subset.
24. A storage medium according to claim 19 , wherein the instructions cause the machine to determine a geolocation of the first scanner when the first scanner determines the base station identifier and a plurality of geolocations of the second scanner when the second scanner determines corresponding ones of the plurality of signal strengths,
wherein the instructions cause the machine to determine that the base station identifier is associated with the subset of the plurality of signal strengths by determining a first geolocation associated with the base station identifier is within a radius of corresponding ones of the plurality of geolocations.
25. A storage medium according to claim 19 , wherein the instructions cause the machine to timestamp the base station identifier and the plurality of signal strengths; and
determine a geolocation of the first scanner when the first scanner determines the base station identifier and a plurality of geolocations of the second scanner when the second scanner determines corresponding ones of the plurality of signal strengths,
wherein the instructions cause the machine to determine that the base station identifier is associated with the subset of the plurality of signal strengths by determining a first timestamp associated with the base station identifier is within a time period of a second timestamp associated with one of the plurality of signal strengths in the subset, and
wherein the instructions cause the machine to determine the base station identifier is associated with the subset of the plurality of signal strengths by determining a first geolocation associated with the base station identifier is within a radius of corresponding ones of the plurality of geolocations.
26. A storage medium according to claim 19 , wherein the first scanner is to detect a second plurality of signal strengths for the frequency.
27. A storage medium according to claim 19 , wherein the second rate is faster than the first rate.