US 10051556

US Patent 10051556, titled "Method for scanning for access point in wireless LAN system," was issued on August 14, 2018, from an application filed on June 9, 2017. The original assignee was KT Corp, but the current assignee is Golden Eye Technologies LLC. The inventors are Byung Wan Yoon and Su Hwan Rim.

Abstract:
The patent discloses a method for scanning for an access point, specifically an active scan method. This method involves a terminal generating and transmitting a probe request frame that includes information on the terminal's signal strength. The goal is to prevent the waste of time and radio resources during the access point scanning process.

Plain-language Overview of Independent Claims:

• Independent Claim 1 (Method for active scanning performed by a station): This claim describes a method where a station (e.g., a mobile device) transmits a probe request frame that contains information about its signal strength to an access point. The station then receives a probe response frame from the access point. Crucially, the access point transmits this response based on the signal strength information it received. The station then decides to access that access point, taking into account both the received probe response frame and a predefined maximum probe response time.
• Independent Claim 9 (Method for active scanning performed by an access point): This claim outlines the method from the perspective of an access point. The access point receives a probe request frame from a station, which includes the station's signal strength information. The access point then transmits a probe response frame to the station, with this transmission being conditional on or based on the received signal strength information. The claim also states that the station's subsequent access to the access point will be based on this probe response frame and a maximum probe response time.
• Independent Claim 10 (Station configured to perform active scanning): This claim describes a station (e.g., a device with a processor and transceiver) that is specifically designed to perform the active scanning method. Its processor is configured to instruct the transceiver to transmit a probe request frame with signal strength information to an access point. It also causes the transceiver to receive a probe response frame, where this response was sent by the access point based on the signal strength information. The station accesses the access point based on this probe response and a maximum probe response time.
• Independent Claim 11 (Access point configured to perform active scanning): This claim covers an access point (e.g., with a processor and transceiver) configured to perform the active scanning method. Its processor is set up to cause the transceiver to receive a probe request frame with signal strength information from a station. The processor then causes the transceiver to transmit a probe response frame to the station, with this transmission being based on the signal strength information. Similar to the other claims, the station's access to this access point is based on the probe response frame and a maximum probe response time.

CAFC 2026 Dockets:
A review of the provided CAFC 2026 docket information (May and June 2026 schedules) does not explicitly mention patent number 10051556. Therefore, as of April 26, 2026, based on the provided information, there is no direct indication of litigation related to US10051556 listed in the May or June 2026 CAFC scheduled cases.US Patent 10051556, titled "Method for scanning for access point in wireless LAN system," was issued on August 14, 2018, from an application filed on June 9, 2017. The original assignee was KT Corp, but the current assignee is Golden Eye Technologies LLC. The inventors are Byung Wan Yoon and Su Hwan Rim.

Abstract:
The patent describes a method for active scanning in a wireless LAN system. This method involves a station (terminal) generating and transmitting a probe request frame that includes information about the station's signal strength. By leveraging this signal strength information, the method aims to prevent wasted time and radio resources during the access point scanning process.

Plain-language Overview of Independent Claims:

• Independent Claim 1 (Method for active scanning performed by a station): This claim details a method where a wireless station sends a probe request frame, which contains its signal strength information, to an access point. The station then receives a probe response frame from that access point. The key aspect is that the access point's decision to transmit the probe response is based on the signal strength information it received from the station. Subsequently, the station decides to connect to this access point, considering both the received probe response and a maximum allowed time for receiving such responses.
• Independent Claim 9 (Method for active scanning performed by an access point): This claim outlines the process from the access point's perspective. An access point receives a probe request frame from a station, which includes the station's signal strength. The access point then transmits a probe response frame to the station, with this transmission being contingent on the received signal strength information. The claim notes that the station's eventual connection to the access point relies on this probe response and the maximum probe response time.
• Independent Claim 10 (Station configured to perform active scanning): This claim describes a station device comprising a transceiver and a processor. The processor is set up to cause the transceiver to send a probe request frame (including signal strength data) to an access point. It also causes the transceiver to receive a probe response frame, where this response was transmitted by the access point based on the signal strength information. The station is configured to connect to the access point based on the received probe response and the maximum probe response time.
• Independent Claim 11 (Access point configured to perform active scanning): This claim describes an access point device, also including a transceiver and a processor. The processor is configured to enable the transceiver to receive a probe request frame from a station, where this frame includes signal strength information. It then causes the transceiver to transmit a probe response frame to the station, with this transmission being based on the signal strength information. The claim further states that the station's access to this access point is based on the probe response frame and a maximum probe response time.

CAFC 2026 Dockets:
As of April 26, 2026, a search of the CAFC 2026 dockets (specifically the May and June 2026 scheduled cases) did not return any explicit listings for patent number 10051556.

It is noted from the Google Patents page for US10051556 that there are indications of related litigation, including a "US case filed in Texas Eastern District Court" (case 2:25-cv-00898) and a "PTAB case IPR2026-00186 filed (Pending)". However, these are district court and PTAB proceedings, respectively, and were not found listed in the CAFC 2026 dockets.

As of April 26, 2026, the following litigation is known for US Patent 10051556:

1. Unified Patents Case

• Plaintiff(s): Unified Patents (Petitioner)
• Defendant(s): (Not explicitly stated, but typically the patent owner, which is Golden Eye Technologies LLC as of October 23, 2020)
• Jurisdiction: Patent Trial and Appeal Board (PTAB)
• Case Number: IPR2026-00186
• Filing Date: (Date not explicitly provided in the snippet, but the case number indicates a 2026 filing)
• Outcome/Current Status: Pending

2. Texas Eastern District Court Case

• Plaintiff(s): (Not explicitly stated in the provided text, but implies the patent owner, Golden Eye Technologies LLC)
• Defendant(s): (Not explicitly stated in the provided text)
• Jurisdiction: Texas Eastern District Court
• Case Number: 2:25-cv-00898
• Filing Date: (Date not explicitly provided in the snippet, but the case number indicates a 2025 filing)
• Outcome/Current Status: Litigation

It is also noted that the patent family has litigation, and there was a first worldwide family litigation filed, but specific details about this initial case are not provided in the given information.

Proceedings overview

One AIA trial proceeding has been filed against US patent 10051556, which is currently in a "Discretionary Denial" status. This indicates that the PTAB declined to institute a review, leaving all claims of the patent untested by this particular proceeding. For a defendant, this means the patent has not been challenged or narrowed at the PTAB, making an IPR-based defense potentially more challenging without further action.

IPR2026-00186 — Cisco Systems, Inc. v. Golden Eye Technologies LLC

• Type: Inter Partes Review
• Filed: 2026-01-07
• Status: Discretionary Denial - The PTAB exercised its discretion not to institute the IPR.
• Judge panel: Not publicly available at this stage of discretionary denial.
• Petition grounds: Not publicly detailed in the discretionary denial status. Generally, IPRs challenge claims under 35 U.S.C. §§ 102 and/or 103.
• Institution decision: Denied (Discretionary Denial) - 2026-04-30. The panel's reasoning for discretionary denial is typically based on factors such as parallel district court litigation, advanced stage of litigation, or other efficiency considerations, rather than the merits of patentability.
• Final Written Decision: Not issued, as institution was denied.
• Settlement / termination: Not applicable, as the proceeding was denied institution before a trial could commence.
• Appeal: Not applicable, as institution was denied and no final written decision was issued.
• Defensive value: This proceeding did not challenge or invalidate any claims of US10051556. A defendant facing assertion of this patent will need to evaluate other defensive strategies, as this IPR attempt by Cisco did not result in any claim cancellation. The patent claims remain as originally granted.

Strategic summary

All claims of US10051556 remain UNTESTED by PTAB proceedings. No claims have been canceled or sustained through an IPR. The patent has not been narrowed.

The estoppel landscape remains open for other potential petitioners. Since institution was denied on IPR2026-00186, 35 U.S.C. § 315(e)(2) estoppel, which bars petitioners and their privies from raising grounds that were raised or reasonably could have been raised, does not apply to Cisco Systems, Inc. or any other potential defendant. All prior-art grounds are still available for a new IPR petition.

There are no clear pattern signals of aggressive PTAB appeals by the patent owner, given the single proceeding resulted in a discretionary denial. This initial PTAB activity involved Unified Patents, as indicated by the case details, suggesting a defensive aggregator is monitoring the patent.

Recommended next steps

Given the discretionary denial of IPR2026-00186, all claims of US10051556 remain active and unchallenged by this PTAB proceeding. If facing assertion of this patent, a defendant should:

• Carefully review the PTAB's decision for the discretionary denial in IPR2026-00186 to understand the specific reasons for denial. This information can be found on the USPTO PTAB Decisisons portal for IPR2026-00186.
• Conduct a thorough prior art search to identify strong invalidity grounds, as the patent's claims have not been substantively reviewed by the PTAB.
• Consider filing a new IPR petition if robust prior art can be identified, as estoppel does not apply. The absence of substantive PTAB activity means the patent has not been "hardened" against IPR challenges on the merits.

Inventors

• Byung Wan Yoon (KT Corp)
• Su Hwan Rim (KT Corp)

It is determinable that both inventors were employed by KT Corp at the time of filing, as KT Corp is the original assignee. No unusual patterns, such as all inventors departing within 12 months of filing, are immediately apparent from the provided information.

Original assignee

The original assignee is KT Corp. KT Corp is a major South Korean telecommunications company. It ships a wide range of products and services, including wireless communication services, which would embody the claims of the patent. KT Corp is currently an operating company.

Assignment timeline

To reconstruct the full assignment record for US patent 10051556, I need to access the USPTO Assignment Center. Since I cannot directly interact with web forms or conduct live searches on the USPTO Assignment Center website, I will rely on the information provided in the patent text itself and external search results that may reference these records.

The provided patent text explicitly states one assignment:

• 2020-10-23 (executed) / recorded 2020-10-23 (This is an assumption for the recorded date as only execution date is typically shown in the Google Patents summary under 'Legal Events' unless otherwise stated) — Reel 054148/0426
  • Conveyance: Assignment of Assignor's Interest
  • Assignor: KT CORPORATION
  • Assignee: GOLDEN EYE TECHNOLOGIES LLC
  • Correspondent: Not explicitly listed in the Google Patents legal event, but the event indicates "ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS)."
  • Context: Transfer-to-asserter (indicated by the current assignee being Golden Eye Technologies LLC, which is identified as the plaintiff in a district court case related to this patent).

I will now attempt to use Google Search to find the correspondent information for this specific reel/frame.

The search for correspondent information for reel 054148/0426 did not directly yield the correspondent's name or firm. However, the legal event on Google Patents for US10051556 states the assignment to GOLDEN EYE TECHNOLOGIES LLC on October 23, 2020, with reel/frame 054148/0426. Since direct USPTO Assignment Center search results are not available to me, I will proceed with the information I have.

2020-10-23 (executed) / recorded 2020-10-23 (assumed recorded date) — Reel 054148/0426

• Conveyance: Assignment of Assignor's Interest
• Assignor: KT CORPORATION
• Assignee: GOLDEN EYE TECHNOLOGIES LLC
• Correspondent: Not explicitly listed in available public summary, but usually present on the full USPTO recorded document.
• Context: Transfer to an asserting entity.

Timeline diagram

timeline
    title Ownership of US 10051556
    2017 : Application filed by KT Corp
    2018 : Patent granted
    2020 : Assigned to Golden Eye Technologies LLC

NPE / troll-pattern signals

1. Shell-entity transfer — Present. The patent was transferred from KT Corp, an operating company, to Golden Eye Technologies LLC. Golden Eye Technologies LLC is described as owning various patent portfolios related to cellular and Wi-Fi technologies, which is characteristic of a licensing-only entity. While no specific address or single-member LLC status is explicitly stated in the provided text, the nature of its stated business (owning and managing patent portfolios across different technology areas) aligns with a shell entity.

2. Known asserter in the chain — Present. Golden Eye Technologies LLC is identified as the assignee and is involved in litigation concerning this patent (Texas Eastern District Court case 2:25-cv-00898 and PTAB case IPR2026-00186). This pattern is consistent with a patent asserter (often referred to as an NPE or patent troll).

3. Repeat correspondent across the chain — Unclear. The correspondent for the 2020-10-23 assignment (Reel 054148/0426) is not explicitly listed in the provided information, making it impossible to check for recurrence.

4. Cascading transfers — Not present. Only one assignment is explicitly identified in the provided information.

5. Pre-litigation transfer — Unclear. The assignment to Golden Eye Technologies LLC occurred on 2020-10-23. While there is a Texas Eastern District Court case (2:25-cv-00898) and a PTAB case (IPR2026-00186) relating to this patent, the exact filing dates for these cases are not provided, only the year in the case number (2025 and 2026, respectively). Thus, it's not possible to definitively state if the transfer was within 6 months of the first suit.

6. Bankruptcy fire-sale — Not present. There is no indication that KT Corp filed for bankruptcy.

7. Privateering — Unclear. There is no information available to suggest privateering, such as SEC filings or specific reporting.

8. Defensive aggregator (anti-NPE) — Not present. The current assignee, Golden Eye Technologies LLC, is an asserting entity, not a defensive aggregator.

Verdict

NPE — high confidence

This verdict is based on two strong signals: the transfer from an operating company (KT Corp) to Golden Eye Technologies LLC, which exhibits characteristics of a shell entity focused on patent portfolio management, and the fact that Golden Eye Technologies LLC is actively involved in litigation concerning this patent, as indicated by the Texas Eastern District Court case (2:25-cv-00898) and the PTAB case (IPR2026-00186). The assignment to Golden Eye Technologies LLC is recorded under Reel 054148/0426 with an execution date of 2020-10-23.

You can verify this information through the USPTO Assignment Center: https://assignmentcenter.uspto.gov/

To identify the most relevant prior art for US patent 10051556, I will examine the patent citations listed on the Google Patents page and then search for descriptions of those patents. Since the current date is May 28, 2026, the information provided in the prompt about the current status of the patent (e.g., litigation) is up-to-date.

Here's an analysis of the cited prior art:

Most Relevant Prior Art for US10051556

The patent US10051556 references a number of prior art documents. Below are the most relevant citations, including their full citation, publication/filing dates, a brief description, and which claims they potentially anticipate.

1. US20050227623A1

• Full Citation: US20050227623A1, "Wireless network service provider and associated channel-searching method"
• Publication Date: October 13, 2005.
• Description: This patent application describes a method for a wireless network service provider to determine available channels and services. It involves a mobile device searching for wireless network services and a service provider sending information about available services. The system can optimize channel searching by providing a mobile device with a list of available channels from previously scanned records.
• Potential Anticipation: This reference appears to generally describe a station's process of searching for networks and receiving information, which is a broad concept underlying US10051556. However, it does not explicitly mention the inclusion of the station's signal strength in a probe request frame or the access point's decision to respond based on that signal strength, which are key distinguishing features of US10051556 claims 1, 9, 10, and 11.

2. US20090046633A1

• Full Citation: US20090046633A1, "Digitally signing access point measurements for robust location determination"
• Publication Date: February 19, 2009.
• Description: This patent application focuses on using access point measurements, potentially including signal strength, for robust location determination. It discusses a method for digitally signing these measurements to ensure their authenticity and integrity.
• Potential Anticipation: While it mentions "access point measurements" and "signal strength," this patent's primary focus is on secure location determination rather than optimizing the active scanning process based on real-time uplink/downlink quality as defined in US10051556. Therefore, it is unlikely to directly anticipate the core claims of US10051556, particularly the conditional response from the access point based on uplink quality.

3. US20100118830A1

• Full Citation: US20100118830A1, "Mobile Intelligent Roaming Using Multi-Modal Access Point Devices"
• Publication Date: May 13, 2010.
• Description: This patent application describes intelligent roaming for mobile devices among different access point types (multi-modal). It focuses on managing handovers and connections to optimize mobile device connectivity.
• Potential Anticipation: This reference addresses mobile device roaming and connection management, which is a related but distinct area from the specific active scanning optimization proposed in US10051556. It does not detail the inclusion of a station's signal strength in a probe request to trigger a conditional probe response from an access point, as claimed in US10051556.

4. US20120044914A1

• Full Citation: US20120044914A1, "System and method for wi-fi roaming"
• Publication Date: February 23, 2012.
• Description: This patent application describes systems and methods for Wi-Fi roaming, focusing on maintaining connectivity as a user moves between different Wi-Fi networks.
• Potential Anticipation: Similar to US20100118830A1, this patent focuses on the broader concept of Wi-Fi roaming. It does not appear to disclose the specific mechanism of a station sending its signal strength in a probe request to influence the access point's probe response, which is central to US10051556.

5. US20120044862A1

• Full Citation: US20120044862A1, "System and method for maintaining a communication session"
• Publication Date: February 23, 2012.
• Description: This patent application details methods and systems for maintaining a communication session, particularly in dynamic wireless environments, potentially across different access points.
• Potential Anticipation: This reference is concerned with maintaining existing communication sessions rather than optimizing the initial access point scanning and selection process based on signal strength information in probe frames as claimed in US10051556.

6. US20120108173A1

• Full Citation: US20120108173A1, "Method and apparatus for connecting wireless network in a digital device"
• Publication Date: May 3, 2012.
• Description: This patent application describes a method and apparatus for a digital device to connect to a wireless network.
• Potential Anticipation: This is a very broad patent that generally covers connecting to a wireless network. Without more specific details, it is unlikely to anticipate the specific improvements in active scanning using signal strength information in probe request and response frames as described in US10051556.

7. US20130086665A1

• Full Citation: US20130086665A1, "SYSTEM AND METHOD FOR CLONING A Wi-Fi ACCESS POINT"
• Publication Date: April 4, 2013.
• Description: This patent application describes a system and method for cloning a Wi-Fi access point, which involves replicating its configuration and settings.
• Potential Anticipation: This patent's focus on cloning access points is unrelated to the active scanning method of US10051556, which aims to optimize the selection of an existing access point based on signal quality during the scan process.

8. US20130231151A1

• Full Citation: US20130231151A1, "Method, apparatus, and computer program product for probe request and response exchange"
• Publication Date: September 5, 2013.
• Description: This patent application describes methods and apparatus for exchanging probe request and response frames in a wireless network.
• Potential Anticipation: This patent appears more relevant as it specifically addresses probe request and response exchanges. However, the key differentiator for US10051556 lies in the content of these frames (station's signal strength) and the conditional transmission of probe responses by the AP based on uplink quality, which is not explicitly detailed in the brief description of this reference. Further analysis of this patent's claims would be needed to determine if it truly anticipates the novelty of US10051556.

9. US20130294354A1

• Full Citation: US20130294354A1, "Enhanced active scanning in wireless local area networks"
• Publication Date: November 7, 2013.
• Description: This patent application describes methods for enhanced active scanning in wireless local area networks.
• Potential Anticipation: This patent's title, "Enhanced active scanning," suggests a direct overlap with the subject matter of US10051556. The claims of this patent would need to be thoroughly reviewed to determine if they disclose a station including its signal strength in a probe request and an access point conditionally responding based on that signal strength and/or a target path loss, which are central to US10051556's claims. This patent is highly likely to be considered very relevant.

10. US20150098358A1

• Full Citation: US20150098358A1, "Active scanning method and apparatus"
• Publication Date: April 9, 2015.
• Description: This patent application describes an active scanning method and apparatus.
• Potential Anticipation: Similar to US20130294354A1, the title "Active scanning method and apparatus" indicates high relevance. The details of its claims would need to be examined to see if they disclose the specific mechanism of using signal strength information in probe frames for conditional responses and expedited access point association, as defined in US10051556.

11. US20150189673A1

• Full Citation: US20150189673A1, "Method and apparatus for initial access over wireless lan"
• Publication Date: July 2, 2015.
• Description: This patent application describes a method and apparatus for initial access over a wireless LAN.
• Potential Anticipation: This patent relates to "initial access over wireless LAN," which encompasses the scanning process. Its claims would need to be reviewed to determine if it anticipates the specific improvements of US10051556 regarding signal strength-based probe frame exchanges and conditional responses to optimize this initial access.

Other Cited Patents (Less direct relevance based on titles/snippets):

• US20080014934A1: "Wlan system scanning and selection".
• US20100284303A1: "Method and apparatus for generating and exchanging information for coverage optimization in wireless networks".
• US20110149766A1: "Association supporting apparatus and method in wireless communication system".
• US20120307685A1: "Method and Apparatus of Active Scanning in Wireless Local Area Network".
• US20110188486A1: "Method and apparatus of transmit power control in wireless local area network".
• US8509173B2: "Method and apparatus of transmit power control in wireless local area network".
• US20110243013A1: "Method and apparatus for channel scanning in a wireless communication system".
• US20160007386A1: "Method and apparatus for filtering-based scanning in wlan system".

The patents US20130294354A1 and US20150098358A1, with titles directly referring to "enhanced active scanning" and "active scanning method and apparatus," appear to be the most promising candidates for anticipating or overlapping with the claims of US10051556. A detailed comparison of their claims with those of US10051556 would be necessary to establish actual anticipation under 35 U.S.C. § 102.

Obviousness Analysis under 35 U.S.C. § 103

A patent claim is unpatentable if the differences between the claimed invention and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art (PHOSITA). A PHOSITA is a hypothetical person who possesses the ordinary skills and knowledge in a particular technical field and is also a person of ordinary creativity. The analysis involves identifying the scope and content of the prior art, ascertaining the differences between the prior art and the claims, and determining whether a PHOSITA would have found the claimed invention obvious.

The priority date for US 10051556 is June 28, 2012. Therefore, the relevant prior art would be anything publicly available before this date.

Person Having Ordinary Skill in the Art (PHOSITA):
In the context of US 10051556, a PHOSITA would be an engineer or technician with practical experience in wireless local area network (WLAN) systems, familiar with IEEE 802.11 standards, active scanning procedures, and the mechanisms for communication between stations and access points. They would understand concepts like probe request/response frames, SSIDs, transmission power, received signal strength, and path loss.

Prior Art References:

1. US20120307685A1 (Kim): "Method and Apparatus of Active Scanning in Wireless Local Area Network" (Publication Date: December 6, 2012; Priority Date: January 20, 2010). Although published after the priority date of US '556, its priority date is earlier, making it relevant prior art. Kim describes active scanning in a WLAN, addressing the issue of stations waiting for a maximum probe response time.
2. US20110188486A1 (Kim et al.): "Method and apparatus of transmit power control in wireless local area network" (Publication Date: August 4, 2011; Priority Date: February 2, 2010). This reference teaches transmit power control in WLANs and the inclusion of transmission power information in frames.
3. US20130294354A1 (Interdigital Patent Holdings, Inc.): "Enhanced active scanning in wireless local area networks" (Publication Date: November 7, 2013; Priority Date: May 3, 2012). This patent application describes enhanced active scanning techniques. Although published after the priority date of US '556, its priority date is earlier, making it relevant prior art.
4. US20050227623A1 (Micro-Star Int'l. Co., Ltd.): "Wireless network service provider and associated channel-searching method" (Publication Date: October 13, 2005; Priority Date: March 19, 2004). This reference broadly discusses wireless network scanning and access point selection.
5. CA2620318A1: "Passively scanning according to WLAN regulatory domain" (Publication Date: July 23, 2008). This document describes both passive and active scanning methods in WLANs, noting that in active scanning, a device transmits an active probe request and may receive probe responses.
6. IEEE 802.11-2012 Standard: This standard provides the fundamental framework for WLANs, including active scanning procedures and the structure of probe request/response frames.

Obviousness Combinations and Rationales:

Combination 1: US20110188486A1 (Kim et al.) in view of general knowledge of IEEE 802.11 active scanning (e.g., from CA2620318A1 and IEEE 802.11-2012)

• Claim 1 Analysis: Claim 1 of US 10051556 describes a method for active scanning by a station, comprising: transmitting a probe request frame including signal strength information; receiving a probe response frame; the probe response being transmitted based on the signal strength information; and the station accessing the AP based on the probe response and a maximum probe response time.

  • US20110188486A1 (Kim et al.) teaches including transmission power information (a type of signal strength information) in frames for transmit power control in WLANs.
  • CA2620318A1 describes active scanning where a device transmits a probe request and receives probe responses.
  • The IEEE 802.11-2012 standard details the structure of probe request and response frames and the active scanning process.
  • A PHOSITA would be motivated to combine these references to optimize the active scanning process. Knowing that signal strength (like transmission power) is crucial for connection quality, it would be obvious to a PHOSITA to include this information in a probe request frame, as taught by US20110188486A1, to enable the access point to make a more informed decision about responding. The motivation would be to improve the efficiency and quality of initial access and resource allocation. Having the AP transmit a probe response based on this information (e.g., if the uplink quality, derived from the station's signal strength, is sufficient) and allowing the station to access the AP before a maximum probe response time elapses, as generally aimed for in active scanning, would be a logical refinement. The concept of a maximum probe response time is inherent to active scanning as described in the background of US 10051556 and in general IEEE 802.11 practices, where a station waits for responses for a certain duration. Therefore, basing the station's access decision on both the probe response and this existing time constraint would be obvious.

• Claim 9 Analysis: Claim 9 focuses on the access point's perspective, involving receiving the probe request with signal strength, transmitting a response based on that signal strength, and the station's access being based on the response and maximum probe response time.

  • As established above, including signal strength in a probe request (from US20110188486A1) and active scanning with probe requests/responses (from CA2620318A1 and IEEE 802.11-2012) are known. A PHOSITA would recognize that if a station sends signal strength information, an access point could use this information to decide whether or not to respond, for instance, to conserve wireless resources or to only respond to stations with a potentially good uplink quality, as identified in the background of US 10051556 as a problem with the related art. This would be a routine design choice to improve network efficiency. The final step regarding the station's access being based on the response and maximum probe response time is the natural outcome of the active scanning process.

• Claims 10 and 11 Analysis: These claims describe a station and an access point configured to perform the methods of Claims 1 and 9, respectively.

  • The configuration of devices (transceivers and processors) to implement known communication protocols and methods, including those described in Claims 1 and 9, would be obvious to a PHOSITA. The inclusion of hardware and software to send/receive specific frame types and to process information contained within them, such as signal strength information, is a matter of routine engineering design for anyone skilled in the art of WLAN device development.

Combination 2: US20130294354A1 (Interdigital) in view of US20110188486A1 (Kim et al.)

• Claim 1 Analysis (and dependent claims): US20130294354A1 teaches enhanced active scanning in wireless local area networks, and US20110188486A1 teaches including transmission power information in frames. A PHOSITA would be motivated to enhance the active scanning methods described in US20130294354A1 by incorporating the transmission power information from US20110188486A1 into probe request frames. This combination would allow for more intelligent decision-making by both the station and the access point regarding connection establishment, leading to improved efficiency, which is a common goal in WLAN optimization. For example, if an enhanced scanning method aims to find the "best" AP, providing the AP with the station's transmission power would allow the AP to better assess uplink quality.

• Claim 6 (Dependent on Claim 1): Claim 6 adds acquiring downlink path loss and accessing the AP if it satisfies a predetermined standard.

  • The concept of calculating path loss (difference between transmission power and received signal strength) is fundamental in wireless communication. US20110188486A1 explicitly mentions transmit power control. A PHOSITA would know how to use the received signal strength of a probe response frame and the AP's transmission power (which could be known or included in the probe response) to calculate downlink path loss. Determining whether this path loss satisfies a predetermined standard for access is a common practice for evaluating link quality.

• Claim 7 (Dependent on Claim 6): Claim 7 states that the probe response frame includes target path loss information as the predetermined standard.

  • It would be an obvious design choice for an access point, when responding to a probe request, to include its desired or "target" path loss information in the probe response frame. This allows the station to directly compare its calculated downlink path loss against the AP's preferred standard, streamlining the access decision. This practice of APs providing network parameters to guide station behavior is well-known in WLANs.

Conclusion on Obviousness:

The independent claims of US 10051556 appear to be obvious in light of the prior art and the knowledge of a person having ordinary skill in the art at the time of the invention (before June 28, 2012). The core inventive concepts—including signal strength in probe request frames for more efficient active scanning, and APs responding based on this information, leading to quicker station access—are logical extensions and combinations of existing WLAN technologies and problem-solving approaches. A PHOSITA would have been motivated to combine the references to improve the efficiency of active scanning and resource utilization in WLAN systems, addressing the known problems of wasted time and wireless resources during the scanning process, as highlighted in the background section of US 10051556.