System and method for detection of mobile operating through a repeater
View Patent ↗A system and method for a network analysis system operating in a wireless communication system with repeaters is disclosed. Embodiments of the system and method enable the network analysis system to determine if signals being received by the network receivers arrive directly from a target mobile appliance or if the signals are passing through a repeater. The repeaters, through an augmentation, measure attributes of a received signal and based on these attributes the system determine whether the signal is served by a repeater or other network device.
1. A proximity location system for locating mobile appliances in a wireless communication system, comprising:
a repeater;
a scanning receiver co-located with the repeater and interfaced to receive signals received at the repeater; and,
a processor operably connected to the scanning receiver;
wherein the scanning receiver is adapted to obtain a channel attribute of a forward channel of one of the mobile appliances and the processor is configured to determine a search window for a corresponding reverse channel of the mobile appliance based upon at least the channel attribute.
2. The wireless communication system of claim 1 , wherein the processor is configured to determine the search window for the corresponding reverse channel of the mobile based upon a predetermined relationship between the forward channel and the reverse channel.
3. The proximity location system of claim 1 , wherein the channel attribute is selected from frequency, spread code, time slot, hopping sequence, or a combination thereof.
4. The proximity location system of claim 1 , wherein the scanning receiver is connected to an antenna of the at least one repeater.
5. The proximity location system of claim 4 , wherein the scanner is configured to measure an attribute of the reverse channel signal.
6. The proximity location system of claim 1 , wherein the scanner is configured to detect the reverse link based on the search window.
7. A method of determining if a mobile is operating in the proximity of a repeater wherein the repeater does not have independent timing synchronization, comprising:
scanning a forward communication signal at a repeater;
obtaining timing information from the forward signal;
determining a search window for a reverse channel of the mobile based on the timing information and a predetermined relationship between the forward channel and the reverse channel;
scanning the search window to detect the reverse channel mobile signal;
measuring an attribute of the mobile reverse channel signal; and,
determining the mobile's proximity based on the measured attribute.
8. The method of claim 7 , wherein the attribute reflects a proximity to the repeater.
9. The method of claim 8 , wherein the attribute is from the group comprising signal strength, signal characteristics, SNR, band of received power, and combinations thereof.
10. A method of determining the proximity of a mobile to a repeater comprising:
scanning and receiving a forward channel signal with a scanning receiver co-located with the repeater;
obtaining channel information from the received forward channel signal;
adjusting a characteristic of the scanning receiver based upon the obtained channel information and a predetermined relationship between the forward channel and a reverse channel;
scanning for a reverse channel signal with the scanner,
measuring one or more attributes of the scanned reverse channel signal; and,
determining the proximity of the mobile to the repeater based at least in part on the measured attribute.
11. The method of claim 10 , wherein the channel information comprises frequency, time slot, spread code, hopping sequence, or a combination thereof.
12. The method of claim 11 , wherein the attribute comprises signal strength, signal to noise ratio (SNR), band of received power, signal characteristics, or a combination thereof.
13. A method of locating a mobile device at a repeater having a co-located scanning receiver, comprising:
monitoring downlink communication at a repeater to obtain timing information associated with the downlink communication;
determining a search window based on the timing information and a predetermined timing relationship between the downlink communication and an uplink communication;
tuning the scanner to scan the search window for the mobile device's uplink communication;
measuring a characteristic of the of the mobile device's uplink communication;
determining the mobile device's proximity to the repeater based on the measured characteristic; and,
determining the location of the mobile based on its proximity to the repeater.
14. The method of claim 13 , wherein the step of determining the location comprises comparing the proximity of the mobile device to the repeater to a threshold.
15. The method of claim 13 , wherein the step of determining a search window includes bounding the estimated uplink transmit time.
16. The method of claim 13 , wherein the step of determining a search window includes bounding an estimated frequency.
17. The method of claim 13 , comprising reporting to a remote processor the mobile identity if it is determined to be proximate to the repeater.