Co-channel wireless detection

• US 10,523,261 B2
• Filed: 03/31/2016
• Issued: 12/31/2019
• Est. Priority Date: 03/31/2016
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Shah, Tushar Ramanlal, Hakim, Joseph
• Primary Examiner(s): Sarwar, Babar
• Application Number:
  US15/087,989
• Publication Number:
  US 20170288723A1
• Time in Patent Office: 1,370 Days
• Field of Search: 4554121-4122, 455418-4221, 455436, 455444, 4555521, 4554561, 455 6711, 455 6713, 455509, 455 411- 412, 370328-332, 370338, 370335, 375316, 375324, 375325, 375340
• CPC Class Codes: H04B 1/16 Circuits
• CPC Class Codes: H04B 1/385 Transceivers carried on the body, e.g. in helmets
• CPC Class Codes: H04B 1/401 for selecting or indicating operating mode
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04B 2001/3855 carried in a belt or harness
• CPC Class Codes: H04B 2001/3861 carried in a hand or on fingers
• CPC Class Codes: H04L 27/0012 arrangements for identifying the type of modulation
• CPC Class Codes: H04L 27/2666 Acquisition of further OFDM parameters, e.g. bandwidth, subcarrier spacing, or guard interval length
• CPC Class Codes: H04L 5/1461 Suppression of signals in the return path, i.e. bidirectional control circuits
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

An electronic device includes an antenna configured to receive a wireless signal. The electronic device also includes a first correlator configured to correlate the wireless signal to a communication of a first wireless protocol type and a second correlator configured to correlate the wireless signal to a communication of a second wireless protocol type.

Claims

1. An electronic device comprising:

an antenna configured to receive a wireless signal;

a first correlator configured to correlate the wireless signal to a communication of a first wireless protocol type, wherein the first wireless protocol type operates using a first frequency band;

a second correlator configured to correlate the wireless signal to a communication of a second wireless protocol type;

wherein the second wireless protocol type operates in a second frequency band, wherein at least one frequency of the second frequency band has a harmonic that falls in the first frequency band;

a harmonics filter coupled to the second correlator; and

a demodulator configured to demodulate the received wireless signal based on results from the first correlator and second correlator of the respective first and second wireless protocol types, wherein the demodulator selectively uses the harmonics filter to filter the harmonic in the received wireless signal from the second correlator based at least in part on the first and second correlator correlating the received wireless signal to both the first wireless protocol type and the second wireless protocol type.

2. The electronic device of claim 1 comprising a comparator that verifies that the wireless signal includes frequencies belonging to the first wireless protocol type.

3. The electronic device of claim 2, wherein the comparator is configured to combine correlation results from the first correlator and correlation results from the second correlator to verify that the wireless signal includes frequencies belonging to the first wireless protocol type.

4. The electronic device of claim 3, wherein the comparator comprises a filter configured to filter out frequencies pertaining to the second wireless protocol type from the wireless signal based at least in part on the correlation results from the second correlator.

5. The electronic device of claim 2, wherein the wireless signal comprises co-channel interference corresponding to the second wireless protocol type.

6. A method comprising:

receiving a wireless signal at an antenna;

passing the wireless signal through a first correlator configured to correlate the wireless signal to a first wireless protocol type, wherein the first wireless protocol type operates using a first frequency band;

passing the wireless signal through a second correlator configured to correlate the wireless signal to a second wireless protocol type;

wherein the second wireless protocol type operates using a second frequency band that does not overlap the first frequency band, wherein at least one frequency of the second frequency band has a harmonic that falls in the first frequency band;

passing the wireless signal from the second correlator to a harmonics filter;

selectively filtering the wireless signal based at least in part on the results of the correlation of first and second correlators; and

demodulating the wireless signal based on results of the first correlator and the second correlator of the respective first and second wireless protocol types.

7. The method of claim 6, wherein passing the wireless signal through the first correlator occurs substantially simultaneously to passing the wireless signal through the second correlator.

8. The method of claim 7 comprising confirming that the wireless signal corresponds to the first wireless protocol type based at least in part on outputs from the first and second correlators.

9. The method of claim 7, wherein:

the first wireless protocol type comprises a wireless connectivity protocol; and

the second wireless protocol type comprises a cellular communication protocol.

10. The method of claim 9, wherein the wireless connectivity protocol comprises a wireless local area network protocol.

11. The method of claim 6 comprising correlating the wireless signal to the first wireless protocol type using an auxiliary correlator to reduce de-sensing caused during correlation prior to filtration of the wireless signal.

12. An electronic device comprising:

an antenna configured to receive a wireless signal

a first correlator configured to generate a first result corresponding to whether the wireless signal correlates to a first wireless protocol type, wherein the first wireless protocol type operates using a first frequency band;

a second correlator configured to generate a second result corresponding to whether the wireless signal correlates to a communication of a second wireless protocol type, wherein the second wireless protocol type operates using a second frequency band, wherein at least one frequency of the second frequency band has a harmonic that falls in the first frequency band;

an inverter configured to invert the second result;

a comparator configured to verify correlation of the wireless signal to the first wireless protocol type based at least in part on results of the second correlator of the second wireless protocol type, wherein the comparator comprises an AND gate configured to receive the first result and the inverted second result and to generate a correlation signal by performing a logic AND on the first result and the inverted second result;

a harmonics filter configured to generate a harmonic-filtered wireless signal by filtering the harmonic from the wireless signal; and

a demodulator configured to;

receive the harmonic-filtered wireless signal and the wireless signal; and

select between demodulating the harmonic-filtered wireless signal and demodulating the wireless signal based at least in part on the correlation signal.

13. The electronic device of claim 12, wherein the first wireless protocol type comprises a wireless local area network protocol.

14. The electronic device of claim 12, wherein the second wireless protocol type comprises a cellular protocol.

15. The electronic device of claim 12 comprising a filter that filters frequencies pertaining to the second wireless protocol if the wireless signal is correlated to the first wireless protocol type and the second wireless protocol type.

16. The electronic device of claim 15, wherein the filter tracks endpoints of a frequency spectrum of a portion of the wireless signal and filters the portion based on the endpoints.

17. The electronic device of claim 15 comprising a plurality of channels each comprising a respective antenna configured to receive a respective wireless signal, wherein each respective antenna is configured to receive signals of a specific wireless protocol, and the antenna is located in a first channel of the plurality of channels.

18. The electronic device of claim 17, wherein the filter tracks endpoints of a frequency spectrum of a portion of the wireless signal and filters the portion based on the endpoints.