Apparatus and method for filtering wireless signals

• US 9,793,937 B2
• Filed: 10/30/2015
• Issued: 10/17/2017
• Est. Priority Date: 10/30/2015
• Status: Active Grant

• Current Assignee: Afero, Inc.
• Original Assignee: Afero, Inc.
• Inventors: Zakaria, Omar, Britt, Joe
• Primary Examiner(s): Nguyen, Duc M
• Application Number:
  US14/927,732
• Publication Number:
  US 20170126262A1
• Time in Patent Office: 718 Days
• Field of Search: 455132, 4555521, 4555531, 4552261, 4552262, 4552263
• CPC Class Codes: H04B 1/1036 with automatic suppression of narrow band noise or interference, e.g. by using tuneable notch filters H04B1/123 takes precedence; filter circuits H03H
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04L 45/745 Address table lookup; Address filtering
• CPC Class Codes: H04L 49/15 Interconnection of switching modules
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication

Abstract

An apparatus and method are described for filtering wireless signals. For example, one embodiment of the invention comprises: one or more radios to receive a plurality of wireless signals within a defined spectrum; an energy detection and filtering module to filter received wireless signals based on a detected energy level of the received wireless signals and in accordance with a set of energy-based filtering parameters, the energy detection and filtering module to output energy-filtered wireless signals; and a signal characteristic analysis and filtering module to analyze and filter the energy-filtered wireless signals based on characteristics of the received wireless signals in accordance with a set of signal analysis filtering parameters to output energy-and-characteristic filtered wireless signals.

Claims

1. An apparatus comprising:

one or more radios to receive a plurality of wireless signals within a defined spectrum;

an energy detection and filtering module to filter received wireless signals based on a detected energy level of the received wireless signals and in accordance with a set of energy-based filtering parameters, wherein the energy detection and filtering module is configured to remove all signals which are below a specified energy threshold, the energy threshold defined by the energy-based filtering parameters, the energy detection and filtering module to output energy-filtered wireless signals;

a signal characteristic analysis and filtering module to analyze and filter the energy-filtered wireless signals based on characteristics of the received wireless signals in accordance with a set of signal analysis filtering parameters to output energy-and-characteristic filtered wireless signals;

wireless device identification logic to analyze the energy-and-characteristic filtered wireless signals for each of a plurality of channels to identify wireless devices sending and/or receiving wireless communications over each channel and to packetize the transmissions using the identity of the sender and/or recipient;

a plurality of wireless networking stacks, each of the wireless networking stacks associated with one of the wireless devices identified by the wireless device identification logic; and

stack forwarding logic to receive packets from the wireless device identification logic and to forward the packets to wireless networking stacks corresponding to each of the wireless devices identified by the wireless device identification logic.

2. The apparatus as in claim 1 wherein the energy detection and filtering module is configured to filter out noise and other unwanted signals within the defined spectrum.

3. The apparatus as in claim 1 wherein the energy-based filtering parameters including the energy thresholds are user programmable for different applications and are set in accordance with a specific set of signals which are desired to be captured and analyzed.

4. The apparatus as in claim 3 wherein the signal characteristic analysis and filtering module is configured to filter the energy-filtered wireless signals based on detected signal bandwidth, signal central frequency, signal modulation scheme, signal behavior, signal duty cycle, carrier type, data rate features, and/or detected compliance or non-compliance with FCC regulations.

5. The apparatus as in claim 4 wherein the signal bandwidth comprises a detected WiFi bandwidth of 20 Mhz, a detected Bluetooth bandwidth of 1 or 2 Mhz, a detected Zigbee bandwidth of 5 Mhz, and a detected Long Term Evolution (LTE) bandwidth of 10 Mhz.

6. The apparatus as in claim 4 wherein the signal center frequency comprises a detected center frequency for WiFi, Bluetooth or Bluetooth LE, and Zigbee.

7. The apparatus as in claim 4 wherein the signal characteristic analysis and filtering module detects signal modulation by applying symbol rate estimation methods to determine the symbol rate, time domain analysis, and/or frequency domain operation.

8. The apparatus as in claim 4 wherein the signal characteristic analysis and filtering module is to detect signal behavior by detecting whether the wireless signal employs frequency hopping and/or detecting a level of burstiness of the energy-filtered wireless signals.

9. The apparatus as in claim 1 wherein the plurality of wireless signals include Bluetooth and Bluetooth LE signals, WiFi signals, cellular data and voice signals, and Zigbee signals.

10. The apparatus as in claim 1 further comprising:

a communication feature extraction module to extract a specified set of features from the digital data stream generated by the radios, the packets generated by the wireless device identification logic and/or the wireless networking stacks, including characteristics of a wireless networking protocol implemented by each of the wireless devices.

11. The apparatus as in claim 10 wherein the wireless network comprises a Bluetooth Low Energy (BTLE) network, the wireless devices comprise BTLE devices, and wherein the characteristics extracted by the communication feature extraction module comprise BTLE communication characteristics.

12. The apparatus as in claim 11 wherein the a separate channel filter and radio is used to separate and demodulate each BTLE channel.

13. The apparatus as in claim 12 wherein the wireless device identification logic is implemented as an application-specific integrated circuit (ASIC) or a field-programmable gate array (FPGA).

14. The apparatus as in claim 13 wherein the plurality of wireless networking stacks are implemented in program code executable by a general purpose processor.

15. The apparatus as in claim 14 wherein the wireless networking stacks comprise BTLE networking stacks.

16. The apparatus as in claim 11 further comprising:

a feature analysis module to analyze the specified set of features and generate a set of analysis results usable to evaluate wireless communication characteristics of the BTLE devices.

17. The apparatus as in claim 16 further comprising a device/channel targeting module to generate wireless interference over one or more of the BTLE channels based on the extracted features and/or the set of analysis results.

18. The apparatus as in claim 17 wherein the extracted features and/or the set of analysis results comprise a frequency hopping pattern extracted by the feature extraction module or determined by the feature analysis module, wherein the device/channel targeting module is configured to generate the wireless interference pattern based on the frequency hopping pattern.

19. The apparatus as in claim 18 wherein the feature extraction module extracts features related to how a particular BTLE device responds to the wireless interference introduced by the device/channel targeting module.

20. The apparatus as in claim 10 further comprising:

a plurality of directional antennas to receive wireless signals for each of the plurality of wireless network channels and to provide the received signals to the plurality of channel filters.

21. The apparatus as in claim 10 further comprising:

a wideband directional antenna shared by each of the plurality of channel filters and the plurality of radios; and

a port combiner to communicatively couple the wideband directional antenna to each of the plurality of channel filters and radios.