Multiple antenna interference rejection in ultra-wideband real time locating systems

• US 9,180,357 B2
• Filed: 07/15/2013
• Issued: 11/10/2015
• Est. Priority Date: 06/06/2013
• Status: Active Grant

• Current Assignee: Zebra Technologies Corporation
• Original Assignee: ZIH Corp. (Zebra Technologies Corporation)
• Inventors: Richley, Edward A.
• Primary Examiner(s): Yu, Lihong
• Application Number:
  US13/942,202
• Publication Number:
  US 20140362892A1
• Time in Patent Office: 848 Days
• Field of Search: 375/130
• US Class Current: 1/1
• CPC Class Codes: A41D 1/002 adapted to accommodate electronic equipment patients' garments for medical monitoring A41D13/1281; luminous ornaments A41D27/085
• CPC Class Codes: A41D 1/005 with embedded cable or connector
• CPC Class Codes: A41D 1/04 Vests, jerseys, sweaters or the like
• CPC Class Codes: A41D 2600/10 for sport activities
• CPC Class Codes: A42B 3/30 Mounting radio sets or communication systems
• CPC Class Codes: A63B 2024/0025 Tracking the path or location of one or more users, e.g. players of a game
• CPC Class Codes: A63B 2024/0028 Tracking the path of an object, e.g. a ball inside a soccer pitch
• CPC Class Codes: A63B 2024/0056 for statistical or strategic analysis
• CPC Class Codes: A63B 2220/12 Absolute positions, e.g. by using GPS
• CPC Class Codes: A63B 2220/40 Acceleration
• CPC Class Codes: A63B 2220/836 Sensors arranged on the body of the user
• CPC Class Codes: A63B 2225/50 Wireless data transmission, e.g. by radio transmitters or telemetry
• CPC Class Codes: A63B 2225/54 Transponders, e.g. RFID
• CPC Class Codes: A63B 24/00 Electric or electronic controls for exercising apparatus of preceding groups; Controlling or monitoring of exercises, sportive games, training or athletic performances
• CPC Class Codes: A63B 24/0021 Tracking a path or terminating locations
• CPC Class Codes: A63B 71/0686 Timers, rhythm indicators or pacing apparatus using electric or electronic means
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G06F 16/951 Indexing; Web crawling techniques
• CPC Class Codes: G06F 16/9537 Spatial or temporal dependent retrieval, e.g. spatiotemporal queries
• CPC Class Codes: G06F 16/955 using information identifiers, e.g. uniform resource locators [URL]
• CPC Class Codes: G06F 16/9554 : by using bar codes
• CPC Class Codes: G06K 7/10227 : loading programming parameters or programs into the interrogator, e.g. for configuring the interrogator
• CPC Class Codes: G06K 7/10297 : arrangements for handling protocols designed for non-contact record carriers such as RFIDs NFCs, e.g. ISO/IEC 14443 and 18092 cryptographic protocols H04L9/00; network security protocols H04L63/00; real-time communication protocols in data switching networks H04L65/00; network protocols for data switching network services H04L67/00
• CPC Class Codes: G06K 7/10306 : ultra wide band
• CPC Class Codes: G06K 7/10366 : the interrogation device being adapted for miscellaneous applications
• CPC Class Codes: G06N 5/02 : Knowledge representation; Symbolic representation
• CPC Class Codes: G06N 7/01 : Probabilistic graphical models, e.g. probabilistic networks
• CPC Class Codes: G06Q 90/00 : Systems or methods specially adapted for administrative, commercial, financial, managerial or supervisory purposes, not involving significant data processing
• CPC Class Codes: G06V 40/23 : Recognition of whole body movements, e.g. for sport training
• CPC Class Codes: G08C 17/02 : using a radio link
• CPC Class Codes: G09B 19/0038 : Sports
• CPC Class Codes: G16H 40/67 : for remote operation
• CPC Class Codes: G16H 50/30 : for calculating health indices; for individual health risk assessment
• CPC Class Codes: G16H 50/50 : for simulation or modelling of medical disorders
• 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 1/7097 : Interference-related aspects
• CPC Class Codes: H04B 1/71635 : Transmitter aspects H04B1/7174 takes precedence
• CPC Class Codes: H04B 1/71637 : Receiver aspects H04B1/7183 takes precedence
• CPC Class Codes: H04B 1/719 : Interference-related aspects
• CPC Class Codes: H04L 43/04 : Processing captured monitoring data, e.g. for logfile generation
• CPC Class Codes: H04Q 9/00 : Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom
• CPC Class Codes: H04W 4/02 : Services making use of location information
• CPC Class Codes: H04W 4/029 : Location-based management or tracking services

Abstract

Systems, methods, apparatuses, and computer readable media are disclosed for providing interference rejection in ultra-wideband real time locating systems. In one embodiment, an ultra-wideband (UWB) receiver is configured to: receive an interference signal from a source positioned outside a monitored region; receive a composite signal transmitted from a tagged object moving about a playing field within the monitored region, wherein the composite signal comprises a location signal and a component of the interference signal; detect whether the component of the interference signal exceeds a threshold value; and adjust, via a processor, filtering of the composite signal to attenuate the component of the interference signal based on whether the component of the interference signal exceeds the threshold value. Some embodiments provide for filtering of the composite signal using a combiner while others employ a tunable notch filter. Corresponding systems, methods, and computer-readable storage medium are also provided.

Claims

1. An ultra-wideband (UWB) receiver comprising:

a first antenna configured to receive a first signal, the first signal comprising a UWB signal and a first component of an interference signal;

a second antenna configured to receive a second signal, the second signal comprising at least a second component of the interference signal; and

a combiner configured to;

receive the first signal from the first antenna;

receive the second signal from the second antenna; and

combine the first signal and the second signal to generate an output signal providing cancellation of at least part of the first component of the inference signal based at least in part on the second component of the interference signal;

a detector configured to;

receive the output signal of the combiner; and

indicate an interference level associated with the output signal;

a controller configured to;

monitor the interference level associated with the output signal; and

adjust at least one of a variable attenuator and a variable phase shifter in an instance in which the monitored interference level is above a threshold level,

the variable attenuator and the variable phase shifter configured to;

modify the second signal received from the second antenna; and

provide the modified second signal to the combiner;

the controller further configured to;

determine a first ratio of a signal strength of the interference signal to a ultra-wideband signal received by the second antenna; and

cause the interference signal and the ultra-wideband signal received by the second antenna to be summed in opposition to the first signal in an instance in which the first ratio is greater than a second ratio of a signal strength of the interference signal to a ultra-wideband signal received by the first antenna; and

the combiner further configured to;

combine the first signal with the summed interference signal and the ultra-wideband signal to enable cancellation of the interference signal.

2. The UWB receiver of claim 1 wherein the first antenna is positioned in a first direction to receive signals transmitted from a monitored region and the second antenna is positioned in a second direction, different from the first direction, to receive signals transmitted from outside the monitored region.

3. The UWB receiver of claim 1 wherein the first component of the interference signal and the second component of the interference signal are generated by one or more communications systems positioned outside of a monitored region.

4. The UWB receiver of claim 1 further comprising:

a superheterodyne receiver, the superheterodyne receiver comprising a narrowband bandpass filter and a detector, the superheterodyne receiver is configured to detect whether at least the second component of the interference signal exceeds the threshold level.

5. The UWB receiver of claim 1 further comprising:

a low noise amplifier; and

a bandpass filter;

the low noise amplifier configured to;

add a predetermined gain to the first signal; and

provide the added gain first signal to the bandpass filter;

the bandpass filter configured to;

filter the added gain first signal to pass frequencies in a UWB frequency band comprising the UWB signal and attenuate frequencies outside the UWB frequency band; and

provide the filtered first signal to the combiner.

6. A method comprising:

receiving a first signal from a first antenna, the first signal comprising a UWB signal and a first component of an interference signal;

receiving a second signal from a second antenna, the second signal comprising at least a second component of the interference signal;

combining, at a combiner, the first signal and the second signal to generate an output signal providing cancellation of at least part of the first component of the inference signal based at least in part on the second component of the interference signal;

determining, by a controller, a first ratio of a signal strength of the interference signal of the second signal to a ultra-wideband signal of the second signal;

causing the interference signal and the ultra-wideband signal of the second signal to be summed in opposition to the first signal in an instance in which the first ratio is greater than a second ratio of a signal strength of the interference signal of the first signal to the ultra-wideband signal of the first signal; and

combining, at the combiner, the first signal with the summed interference signal and the ultra-wideband signal of the second signal to enable cancellation of the interference signal.

7. The method of claim 6 further comprising:

modifying, by a variable attenuator and a variable phase shifter, the second signal received from the second antenna; and

providing the modified second signal to the combiner for combining with the first signal.

8. The method of claim 7 further comprising:

receiving, at a detector, the output signal of the combiner, and

generating an indication of an interference level associated with the output signal;

monitoring, by a controller, the interference level associated with the output signal; and

adjusting, by the controller, at least one of a variable attenuator and a variable phase shifter in an instance in which the monitored interference level is above a threshold level.

9. The method of claim 8 further comprising detecting, via a superheterodyne receiver, whether at least the second component of the interference signal exceeds the threshold level.

10. The method of claim 6 wherein the first antenna is positioned in a first direction to receive signals transmitted from a monitored region and the second antenna is positioned in a second direction, different from the first direction, to receive signals transmitted from outside the monitored region.

11. The method of claim 6 wherein the first component of the interference signal and the second component of the interference signal are generated by one or more communications systems positioned outside of a monitored region.

12. The method of claim 6 further comprising:

adding a predetermined gain to the first signal;

filtering the added gain first signal to pass frequencies in a UWB frequency band comprising the UWB signal and attenuating frequencies outside the UWB frequency band; and

providing the filtered first signal to the combiner.

13. An ultra-wideband (UWB) system comprising:

one or more UWB transmitters, each configured to transmit a UWB signal; and

one or more UWB receivers, the one or more UWB receivers comprising;

a first antenna configured to receive a first signal, the first signal comprising the UWB signal and a first component of an interference signal;

a second antenna configured to receive a second signal, the second signal comprising at least a second component of the interference signal;

a combiner configured to;

receive the first signal from the first antenna;

receive the second signal from the second antenna; and

combine the first signal and the second signal to generate an output signal providing cancellation of at least part of the first component of the inference signal based at least in part on the second component of the interference signal;

a detector configured to;

receive the output signal of the combiner; and

indicate an interference level associated with the output signal;

a controller configured to;

monitor the interference level associated with the output signal; and

adjust at least one of a variable attenuator and a variable phase shifter in an instance in which the monitored interference level is above a threshold level;

the variable attenuator and the variable phase shifter configured to;

modify the second signal received from the second antenna; and

provide the modified second signal to the combiner

the controller further configured to;

determine a first ratio of a signal strength of the interference signal to a ultra-wideband signal received by the second antenna; and

cause the interference signal and the ultra-wideband signal received by the second antenna to be summed in opposition to the first signal in an instance in which the first ratio is greater than a second ratio of a signal strength of the interference signal to a ultra-wideband signal received by the first antenna; and

the combiner further configured to;

combine the first signal with the summed interference signal and the ultra-wideband signal to enable cancellation of the interference signal.

14. The UWB system of claim 13 wherein the first antenna is positioned in a first direction to receive signals transmitted from a monitored region and the second antenna is positioned in a second direction, different from the first direction, to receive signals transmitted from outside the monitored region.

15. The UWB system of claim 13 wherein the first component of the interference signal and the second component of the interference signal are generated by one or more communications systems positioned outside of a monitored region.

16. The UWB system of claim 13 wherein the one or more UWB receivers further comprise a superheterodyne receiver, the superheterodyne receiver comprising a narrowband bandpass filter and a detector, the superheterodyne receiver is configured to detect whether at least the second component of the interference signal exceeds the threshold value.