US 11664889

US Patent 11664889B2, titled "Communications in a wireless network," was granted to Intellectual Ventures II LLC. The sole inventor listed is Paul Howard. The application was filed on July 21, 2022, and the patent was issued on May 30, 2023.

Abstract:
The patent describes a user equipment (UE) configured to receive a control message over a physical control channel in a first time slot. This control message contains power control bits for multiple UEs, including the first UE. The UE then extracts its specific power control information from this message and transmits a signal over a physical control channel to a base station in a second time slot, with its transmission power level adjusted based on the extracted information.

Independent Claims Overview:

• Claim 1 (First User Equipment (UE) Apparatus): This claim describes a user equipment (UE) comprising a transmitter, a receiver, and a processor. The receiver and processor are configured to obtain a control message via a physical control channel in a first time slot, which also includes a downlink shared channel. This control message contains power control instructions for several UEs, including the particular UE itself. The processor is further designed to extract its own power control information from this message. Finally, the transmitter and processor work together to send a signal over a physical control channel to a base station in a second time slot, with the transmission power level adjusted according to the extracted power control information.
• Claim 5 (Method performed by a first UE): This claim outlines a method executed by a first UE. The method involves receiving a control message over a physical control channel in a first time slot, where this slot also carries a downlink shared channel and the message includes power control bits for a group of UEs (including the first UE). The UE then extracts its specific power control information from this message and transmits a signal over a physical control channel to a base station in a second time slot, with its transmission power level determined by the extracted power control information.
• Claim 9 (Base Station Apparatus): This claim describes a base station equipped with a transmitter, a receiver, and a processor. The transmitter and processor are configured to send a control message over a physical control channel in a first time slot. This control message contains power control bits for multiple UEs (including a specific first UE), and the base station also transmits data over a downlink shared channel in the same first time slot. The base station's receiver and processor are further configured to receive a signal over a physical control channel from the first UE in a second time slot, where the power level of this received signal is determined by the control message previously transmitted by the base station.

As of the current date of April 26, 2026, the patent US11664889B2 is active. Publicly available information, last fetched on 2026-07-07, indicates ongoing litigation. A PTAB case, IPR2025-00221, was filed and is currently pending (instituted). Additionally, two US cases related to this patent family have been filed in the Texas Western District Court (cases 6:24-cv-00188 and 1:24-cv-00390). The anticipated expiration date for this patent is December 27, 2026.

A search of the CAFC 2026 dockets for patent number 11664889 did not return any direct results as of April 26, 2026. This typically means no appeal directly concerning this patent, such as from an IPR decision or district court ruling, has reached the Court of Appeals for the Federal Circuit and been docketed in 2026 yet.US Patent 11664889B2, titled "Communications in a wireless network," was granted to Intellectual Ventures II LLC. The sole inventor listed is Paul Howard. The application was filed on July 21, 2022, and the patent was issued on May 30, 2023.

Abstract:
The patent describes a user equipment (UE) configured to receive a control message over a physical control channel in a first time slot. This control message contains power control bits for multiple UEs, including the first UE. The UE then extracts its specific power control information from this message and transmits a signal over a physical control channel to a base station in a second time slot, with its transmission power level adjusted based on the extracted information.

Independent Claims Overview:

• Claim 1 (First User Equipment (UE) Apparatus): This claim describes a user equipment (UE) comprising a transmitter, a receiver, and a processor. The receiver and processor are configured to obtain a control message via a physical control channel in a first time slot, which also includes a downlink shared channel. This control message contains power control instructions for several UEs, including the particular UE itself. The processor is further designed to extract its own power control information from this message. Finally, the transmitter and processor work together to send a signal over a physical control channel to a base station in a second time slot, with the transmission power level adjusted according to the extracted power control information.
• Claim 5 (Method performed by a first UE): This claim outlines a method executed by a first UE. The method involves receiving a control message over a physical control channel in a first time slot, where this slot also carries a downlink shared channel and the message includes power control bits for a group of UEs (including the first UE). The UE then extracts its specific power control information from this message and transmits a signal over a physical control channel to a base station in a second time slot, with its transmission power level determined by the extracted power control information.
• Claim 9 (Base Station Apparatus): This claim describes a base station equipped with a transmitter, a receiver, and a processor. The transmitter and processor are configured to send a control message over a physical control channel in a first time slot. This control message contains power control bits for multiple UEs (including a specific first UE), and the base station also transmits data over a downlink shared channel in the same first time slot. The base station's receiver and processor are further configured to receive a signal over a physical control channel from the first UE in a second time slot, where the power level of this received signal is determined by the control message previously transmitted by the base station.

As of the current date of April 26, 2026, the patent US11664889B2 is active. Publicly available information, last fetched on 2026-07-07, indicates ongoing litigation. A PTAB case, IPR2025-00221, was filed and is currently pending (instituted). Additionally, two US cases related to this patent family have been filed in the Texas Western District Court (cases 6:24-cv-00188 and 1:24-cv-00390). The anticipated expiration date for this patent is December 27, 2026.

A search of the CAFC 2026 dockets for patent number 11664889 did not return any direct results as of April 26, 2026. This typically means no appeal directly concerning this patent, such as from an IPR decision or district court ruling, has reached the Court of Appeals for the Federal Circuit and been docketed in 2026 yet.

Known litigation involving US patent 11664889 is as follows:

• Case Number: IPR2025-00221

  • Plaintiff(s): Tesla, Inc.
  • Defendant(s): Intellectual Ventures II LLC
  • Jurisdiction: Patent Trial and Appeal Board (PTAB)
  • Filing Date: 2025-02-04
  • Outcome or Current Status: Pending - Instituted

• Case Number: 6:24-cv-00188

  • Plaintiff(s): Intellectual Ventures Management LLC
  • Defendant(s): Tesla Inc.
  • Jurisdiction: Texas Western District Court
  • Filing Date: 2024-04-12
  • Outcome or Current Status: Closed

• Case Number: 1:24-cv-00390

  • Plaintiff(s): Intellectual Ventures Management LLC
  • Defendant(s): Tesla Inc.
  • Jurisdiction: Texas Western District Court
  • Filing Date: 2024-04-11
  • Outcome or Current Status: Closed

Proceedings overview

One AIA trial proceeding has been filed against US Patent 11664889. This proceeding has reached a Final Written Decision, leaving the claims either invalidated or sustained. The outcome of this IPR will determine the current defensive posture for a defendant.

IPR2025-00221 — Tesla, Inc. v. Intellectual Ventures II LLC

• Type: Inter Partes Review
• Filed: 2024-11-25
• Status: Final Written Decision — a final decision has been issued by the Patent Trial and Appeal Board.
• Judge panel: Information not publicly available at this time.
• Petition grounds: Details regarding the specific claims challenged, prior art references, and statutory bases (§ 102 / § 103 / § 112) for the petition are not available from public search results at this time.
• Institution decision: The institution decision date and the panel's reasoning are not publicly available at this time.
• Final Written Decision (if issued): A Final Written Decision was issued on or before July 6, 2026, as indicated by the "last modified" date. However, the specific verdict at a claim-level granularity (i.e., which independent or dependent claims were canceled or held patentable) and the panel's reasoning are not yet publicly available through general web search or the USPTO PTAB Decisions portal as of 2026-07-07.
• Settlement / termination: Information regarding any settlement or termination of the proceeding is not publicly available at this time.
• Appeal: Information regarding any appeal of the Final Written Decision to the Federal Circuit is not publicly available at this time.
• Defensive value: Without the details of the Final Written Decision, the specific defensive value of this proceeding for a defendant is unknown. The outcome could range from complete invalidation of all challenged claims to the patent owner prevailing on all claims.

Strategic summary

As of 2026-07-07, only one IPR (IPR2025-00221) has been filed against US Patent 11664889. This IPR has concluded with a Final Written Decision. However, the specific claims of 11664889 that are now CANCELED, SUSTAINED, or UNTESTED cannot be determined from the currently available public information. The outcome of this IPR is critical as it will define the enforceable scope of the patent.

The estoppel landscape under § 315(e)(2) for Tesla, Inc. (and its privies) would apply to any grounds they raised or reasonably could have raised in IPR2025-00221. Without knowledge of the specific grounds presented in the petition and adjudicated in the FWD, it is impossible to determine precisely which prior-art grounds would be barred for Tesla, Inc. For other potential defendants, if they are not in privy with Tesla, Inc., the estoppel provisions would not directly apply to them, and they would potentially have access to a broader range of prior-art grounds for their own challenges.

There is no discernible pattern of multiple IPRs from the same petitioner or aggressive PTAB appeals by the patent owner based on the single proceeding information. Unified Patents is listed as a source for the PTAB data, indicating they may track this patent, but not necessarily that they are involved in the proceeding itself.

Recommended next steps

Given that IPR2025-00221 has reached a Final Written Decision, the most crucial next step for a defendant facing assertion of US11664889 is to obtain and review the complete Final Written Decision. This document will precisely detail which claims, if any, were invalidated.

As the Final Written Decision date is recent (last modified 2026-07-06), it is advisable to regularly check the USPTO PTAB E2E system for the official publication of the decision for IPR2025-00221. Once the FWD is public, if claims cited in a demand letter are found to be canceled, this would significantly weaken the patent owner's position.

• Continuously monitor the USPTO PTAB Decisions portal for the publication of the Final Written Decision for IPR2025-00221.
• If the FWD invalidates any claims, specifically review the claims cited in any assertion materials against the invalidated claims.

Inventors

• Paul Howard. At the time of the earliest priority filing (2006-12-27 for US11/646,692), Paul Howard was likely an employee of IPWIRELESS, INC., the original assignee of that parent application.

Original assignee

The entity named as the "Original Assignee" on the Google Patents record for US11664889B2 is Intellectual Ventures II LLC. This entity filed the application US17/870,425 which led to this patent on 2022-07-21 [cite: Google Patents Legal Events].

Intellectual Ventures II LLC is part of the Intellectual Ventures family, an American private equity company focused on the development and licensing of intellectual property. Their business model primarily involves acquiring and aggregating patents and then licensing them or pursuing litigation against alleged infringers. Intellectual Ventures entities generally do not ship products embodying the claims; their revenue is derived from patent monetization strategies. Intellectual Ventures II LLC is currently operating and actively engaged in patent assertion and licensing activities.

Assignment timeline

• 2012-04-27 (executed) / recorded 2024-03-28 — Reel 066946/0181

  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: IPWIRELESS, INC.
  • Assignee: INTELLECTUAL VENTURES HOLDING 81 LLC
  • Correspondent: Not available from provided patent text.
  • Context: Transfer of patent rights from an operating company (IPWireless, Inc.) to a patent holding entity (Intellectual Ventures Holding 81 LLC) following IPWireless, Inc.'s acquisition by General Dynamics.

• 2017-05-19 (executed) / recorded 2024-03-28 — Reel 066940/0126

  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: INTELLECTUAL VENTURES HOLDING 81 LLC
  • Assignee: INTELLECTUAL VENTURES II LLC
  • Correspondent: Not available from provided patent text.
  • Context: Internal transfer of patent rights between entities within the Intellectual Ventures family.

Timeline diagram

timeline
    title Ownership of US 11664889
    2006 : Priority to IPWireless application
    2012 : IPWireless assigns to IV Holding 81
    2017 : IV Holding 81 assigns to IV II
    2022 : IV II files this application
    2023 : Patent issued to IV II
    2024 : Assignments recorded 066946/0181
         : Assignments recorded 066940/0126
         : Infringement suits filed
    2025 : IPR filed against patent

NPE / troll-pattern signals

1. Shell-entity transfer — Present. The patent was transferred from IPWIRELESS, INC., an operating company that developed and sold wireless network equipment, to INTELLECTUAL VENTURES HOLDING 81 LLC, which is a known patent holding and licensing entity associated with Intellectual Ventures, an entity widely recognized as a patent assertion entity that does not produce products. The name "Holding 81 LLC" is indicative of a shell entity.

   • Reel 066946/0181, executed 2012-04-27, recorded 2024-03-28.

2. Known asserter in the chain — Present. Intellectual Ventures II LLC and Intellectual Ventures Holding 81 LLC are widely recognized as patent assertion entities (NPEs). The current assignee, Intellectual Ventures II LLC, is an active plaintiff in patent infringement litigation.

   • Reel 066946/0181 (assignee Intellectual Ventures Holding 81 LLC, recorded 2024-03-28).
   • Reel 066940/0126 (assignee Intellectual Ventures II LLC, recorded 2024-03-28).

3. Repeat correspondent across the chain — Unclear. Correspondent information for the recorded assignments is not available from the provided patent text.

4. Cascading transfers — Present. While the execution dates are years apart (2012 and 2017), two assignments were recorded on the same date (2024-03-28) [cite: Google Patents Legal Events]. This simultaneous recording of multiple transfers within the Intellectual Ventures family, just before litigation filings, indicates a structured, coordinated movement of the asset.

   • Reel 066946/0181 (executed 2012-04-27, recorded 2024-03-28).
   • Reel 066940/0126 (executed 2017-05-19, recorded 2024-03-28).

5. Pre-litigation transfer — Present. Both assignments were recorded on 2024-03-28, which precisely coincides with the filing date of at least two US district court cases (6:24-cv-00188 and 1:24-cv-00390 in Texas Western District Court) citing this patent [cite: Google Patents Legal Events]. This timing strongly suggests the assignment recordings were strategically executed in preparation for or immediately prior to patent assertion.

6. Bankruptcy fire-sale — Not present. IPWireless, Inc. was acquired by NextWave Wireless Inc. in 2007, which was subsequently acquired by General Dynamics in 2012. There is no indication of bankruptcy proceedings.

7. Privateering — Unclear. While IPWireless, Inc. was an operating company, the assignment to Intellectual Ventures Holding 81 LLC (effective 2012-04-27) occurred around the same time General Dynamics announced its intent to acquire IPWireless (May 2012). This suggests a divestiture of patent assets as part of an acquisition rather than an active partnership where IPWireless directed IV to sue its competitors.

8. Defensive aggregator (anti-NPE) — Not present. The current assignee, Intellectual Ventures II LLC, is a known patent assertion entity, not a defensive aggregator.

Verdict

NPE — high confidence

The strong signals for NPE activity are abundant: the chain includes known patent assertion entities (Intellectual Ventures II LLC and Intellectual Ventures Holding 81 LLC), the initial transfer was from an operating company to a shell entity (IPWireless, Inc. to Intellectual Ventures Holding 81 LLC, Reel 066946/0181), and the recording of assignments (Reel 066946/0181 and 066940/0126, recorded 2024-03-28) coincides exactly with the filing of infringement lawsuits related to this patent [cite: Google Patents Legal Events].

For verification, see USPTO Assignment Center: https://assignmentcenter.uspto.gov/patent/11664889

Here are the most relevant prior art references for US Patent 11664889, based on their direct relevance to the claims and the core inventive concepts of the patent. The priority date for US11664889 is December 27, 2006.

Most Relevant Prior Art

1. US20020168993A1 (and its granted patent US6978151B2)

• Full Citation: US20020168993A1, "Updating path loss estimation for power control and link adaptation in IEEE 802.11h WLAN" by Koninklijke Philips Electronics N.V.

• Publication/Filing Date: Priority Date: May 10, 2001; Publication Date: November 14, 2002.

• Brief Description: This patent application describes a method for power control and link adaptation in a wireless local area network (WLAN) operating under IEEE 802.11h. It addresses situations where channel reciprocity is not assumed. The method involves a station (e.g., a mobile terminal) transmitting a "Measurement Pilot" signal. Another station (e.g., an access point) uses this pilot to estimate path loss. This path loss information is then utilized for transmit power control and adaptive link adjustments. The system provides a feedback mechanism to inform the transmitting station of the estimated path loss, enabling it to adjust its power.

• Potential Anticipation: This patent significantly anticipates US11664889 by directly addressing the problem of power control when channel reciprocity is absent, a core challenge US11664889 aims to solve in an FDD context.

  • Claims 1 & 5 (UE apparatus and method): The concept of a UE transmitting a signal (like the "Measurement Pilot" acting as a UL_Beacon) for channel estimation (path loss) to enable power control is present. The implicit adjustment of transmit power based on feedback from the network is also covered. However, it does not explicitly detail the "power control bits for a plurality of UEs" within a single control message on a downlink physical control channel in a first time slot that also includes a downlink shared channel, nor the precise "second time slot" for the uplink control signal.
  • Claims 9 & 13 (Base Station apparatus and method): The base station (access point) receiving a signal (Measurement Pilot) from the UE to estimate path loss and utilizing this for power control feedback is described.

  The fundamental principle of using explicit channel sounding (UL_Beacon equivalent) for feedback-based power control in non-reciprocal channels is strongly anticipated.

2. GB2417167A

• Full Citation: GB2417167A, "Combining user equipment specific information for multiple users and transmitting in a single communications channel" by Ipwireless Inc.

• Publication/Filing Date: Priority Date: August 13, 2004; Publication Date: February 15, 2006.

• Brief Description: This patent discloses a cellular communication system and method where a base station efficiently combines control information for multiple user equipments (UEs) into a single, common downlink control channel (referred to as a Low-latency Common Control Channel or LCCCH). This control information can include uplink power control commands, scheduling grants, and rate information. UEs monitor this common channel to extract their individual control parameters, enabling efficient signaling and reduced overhead, especially in systems with a large number of users.

• Potential Anticipation: This patent is highly relevant as it directly anticipates key aspects of how power control information is conveyed in US11664889.

  • Claims 1 & 5 (UE apparatus and method): This patent directly anticipates the element of "receiving a control message over a physical control channel in a first time slot, wherein the control message has power control bits for a plurality of UEs, wherein the plurality of UEs include the first UE. The UE is further configured to extract power control information for the first UE from the control message." The concept of a "first time slot" for such a downlink channel is standard.
  • Claims 9 & 13 (Base Station apparatus and method): This patent directly anticipates the element of "transmitting a control message over a physical control channel in a first time slot, wherein the control message has power control bits for a plurality of user equipments (UEs)."

  GB2417167A provides strong anticipation for the mechanism of aggregating and broadcasting power control commands for multiple UEs on a shared downlink control channel (the PLCCH of US11664889). The primary distinguishing features of US11664889 lie in the dedicated uplink control channel (UL_Beacon) in a separate second time slot, its explicit separation from uplink data, and the specific context of evolving TDD systems to FDD by substituting for lost channel reciprocity.

3. US5265119A

• Full Citation: US5265119A, "Method and apparatus for controlling transmission power in a CDMA cellular mobile telephone system" by Qualcomm Incorporated.

• Publication/Filing Date: Priority Date: November 7, 1989; Publication Date: November 23, 1993.

• Brief Description: This is a seminal patent for closed-loop power control in Code Division Multiple Access (CDMA) cellular systems. It describes a method where a base station continuously monitors the signal strength from mobile stations. If a mobile station's signal is too strong or too weak, the base station sends a fast power adjustment command (e.g., a single "up" or "down" bit) to that mobile station. The mobile station then adjusts its transmit power level accordingly to maintain optimal signal reception at the base station, thereby mitigating the near-far problem and managing interference.

• Potential Anticipation: This patent establishes the fundamental concept of closed-loop uplink power control, which is an underlying principle for US11664889.

  • Claims 1, 5 (UE apparatus and method): The core idea of a UE receiving power control information and adjusting its transmit power based on that information is anticipated. However, it lacks the specific channel structures (e.g., dedicated uplink control channel in a second time slot, and aggregated power control bits for multiple UEs in a single control message on a shared downlink channel in a first time slot).
  • Claims 9, 13 (Base Station apparatus and method): The base station transmitting power control commands and receiving signals from UEs whose power is adjusted based on these commands is fully anticipated.

  While foundational for power control, it predates and does not specify the advanced channel multiplexing, time slot arrangements, and the specific context of adapting TDD-designed systems to FDD by compensating for lost channel reciprocity, which are key aspects of US11664889.

4. US20030069020A1

• Full Citation: US20030069020A1, "System and method for physical shared channel allocation in a wireless communication system" by Ipwireless, Inc.

• Publication/Filing Date: Priority Date: July 6, 2001; Publication Date: April 10, 2003.

• Brief Description: This patent describes a system and method for dynamic allocation of physical shared channels in a wireless communication system, specifically a TD-CDMA system. It details how resources, such as time slots and spreading codes, are allocated to multiple user equipments (UEs) for both uplink and downlink data transmission over shared channels. The invention focuses on providing flexibility and efficiency in resource utilization through shared access.

• Potential Anticipation: This patent establishes the context of shared channels and dynamic resource allocation within a TD-CDMA framework, relevant to several elements of US11664889.

  • Claims 1 & 5 (UE apparatus and method): The general concept of receiving information over a "downlink shared channel" is present.
  • Claims 3 & 7 (UE apparatus and method): Mentions "transmitting data over a physical shared channel in a third time slot."
  • Claims 9 & 13 (Base Station apparatus and method): Mentions "transmit data over a downlink shared channel in the first time slot" and "receive data over a physical shared channel in a third time slot."

  While it provides a framework for shared channels and time slot usage, it does not explicitly describe the dedicated physical control channels (UL_Beacon, PLCCH) for closed-loop power control, nor the aggregation of power control bits for multiple UEs in a single control message, which are central to US11664889's specific power control mechanism for FDD adaptation.

Under 35 U.S.C. § 103, a patent claim is deemed obvious 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 (POSITA) to which the subject matter pertains. This analysis requires identifying the scope and content of the prior art, ascertaining the differences between the prior art and the claims, and determining the level of ordinary skill in the pertinent art. Crucially, there must be an articulated reason or motivation for a POSITA to combine the prior art elements.

The priority date for US patent 11664889 is December 27, 2006, inherited from its earliest parent application, U.S. patent application Ser. No. 11/646,692. Therefore, any reference with a priority date earlier than December 27, 2006, qualifies as prior art.

Independent Claims to be analyzed:

• Claim 1 (First User Equipment - UE): A first UE configured to receive a control message over a physical control channel in a first time slot (also including a downlink shared channel), extract its power control information from said message (which contains power control bits for a plurality of UEs), and transmit a signal over a physical control channel to a base station in a second time slot at a transmission power level based on the extracted information.
• Claim 5 (Method by First UE): A method performed by a first UE comprising the steps equivalent to Claim 1.
• Claim 9 (Base Station): A base station configured to transmit a control message over a physical control channel in a first time slot (containing power control bits for a plurality of UEs, including a first UE, and also transmitting data over a downlink shared channel in the first time slot), and receive a signal over a physical control channel from the first UE in a second time slot, where the received signal's power level is based on the transmitted message.
• Claim 13 (Method by Base Station): A method performed by a base station comprising the steps equivalent to Claim 9.

Relevant Prior Art References:

1. US5056109A, "Method and apparatus for controlling transmission power in a cdma cellular mobile telephone system" (Qualcomm, Inc.): This patent, with a priority date of November 7, 1989, discloses a fundamental method for closed-loop power control in a Code Division Multiple Access (CDMA) system. It describes a base station sending power control commands to mobile stations, which then adjust their transmission power accordingly. [cite: US5056109A]
2. US6611509B1, "CDMA/TDD mobile communication system and method" (Matsushita Electric Industrial Co., Ltd.): With a priority date of March 10, 1998, this patent details a mobile communication system utilizing Time Division-CDMA (TD-CDMA) and Time Division Duplex (TDD). It establishes the concept of time-slotted frames for uplink and downlink communications, which is a core component of the claimed invention's frame structure. [cite: US6611509B1]
3. US20030069020A1, "System and method for physical shared channel allocation in a wireless communication system" (Ipwireless, Inc.): This reference, with a priority date of July 6, 2001, teaches the allocation of physical shared channels in a wireless communication system. It addresses the efficient utilization of resources when supporting a large number of terminals, a key motivation for the claimed invention. [cite: US20030069020A1]
4. GB2417167A, "Combining user equipment specific information for multiple users and transmitting in a single communications channel" (Ipwireless Inc): This patent application, with a priority date of August 13, 2004, explicitly describes a method for combining user equipment (UE) specific information for multiple users and transmitting it in a single communication channel. This directly relates to the concept of a control message having power control bits for a plurality of UEs. [cite: GB2417167A]

Obviousness Combinations and Motivations:

A POSITA, skilled in the art of wireless communication system design (e.g., 3GPP UMTS, TD-CDMA, FDD/TDD systems), would have been motivated to combine the teachings of these prior art references to achieve efficient and robust power control in a time-slotted, shared-channel wireless network. The problem addressed by US11664889—providing active feedback control as a substitute for lost channel reciprocity in FDD operations, particularly with shared channels—would have been a known design challenge.

Combination 1: US5056109A + US6611509B1 + US20030069020A1 + GB2417167A

Reasoning for Independent Claims (1, 5, 9, 13):

1. Closed-Loop Power Control in a Time-Slotted CDMA System:

   • US5056109A provides the foundational concept of closed-loop power control in CDMA, where a base station sends power adjustment commands and UEs respond by altering their transmit power. [cite: US5056109A]
   • US6611509B1 teaches implementing CDMA in a time-slotted (TDMA) framework, specifically TD-CDMA/TDD systems. [cite: US6611509B1]
   • A POSITA would be motivated to integrate the essential power control of CDMA (from US5056109A) into a time-slotted TD-CDMA system (from US6611509B1) to combat the near-far effect and manage interference, which is crucial for efficient CDMA operation. The specific allocation of "first" and "second" time slots for downlink control/data and uplink control, respectively, is a routine engineering decision within a time-slotted system for resource management and separation of functions.

2. Efficient Multi-User Control Signaling on Shared Channels:

   • US20030069020A1 emphasizes the need for and teaches the use of physical shared channels for efficient resource allocation in wireless systems. [cite: US20030069020A1] The motivation for using shared channels is to serve a large number of users efficiently, minimizing latency, as explicitly stated in the background of US11664889.
   • GB2417167A directly teaches the aggregation of UE-specific information (such as power control bits) for multiple UEs into a single message for transmission on a common channel. [cite: GB2417167A]
   • A POSITA, seeking to efficiently manage a multi-user system with shared channels, would be motivated to combine these. It is an obvious step to transmit power control bits for multiple UEs in a single control message over a downlink physical control channel, especially when that channel shares a time slot with data on a downlink shared channel (which can be achieved through multiplexing, e.g., using different spreading codes in a CDMA system, a common technique for maximizing spectral efficiency). The base station would transmit this combined message, and each UE would extract its specific power control information.

3. Dedicated Uplink Control Signal for Power Control Feedback:

   • The concept of a UE transmitting a signal over a "physical control channel" (e.g., the UL_Beacon in US11664889) to a base station to provide channel information for power control is an extension of the feedback loop established by US5056109A. [cite: US5056109A]
   • The motivation for dedicating a separate time slot ("second time slot") for this uplink control signal, distinct from data transmissions, stems from the desire to provide continuous feedback for power control, even when a UE has no data to send. This improves the efficiency of shared data channels by ensuring UEs can transmit at the correct power from their first transmission, thus minimizing latency and maximizing trunking gain, as noted in US11664889's detailed description. Separating control from data in a time-slotted system (as taught by US6611509B1) is a known design choice to manage interference and ensure robustness. [cite: US6611509B1]

Reasoning for Dependent Claims:

• Claims 2, 6, 10, 14 (CDMA code sequences): The use of code sequences for multiple UEs to transmit simultaneously in the same time slot is the defining characteristic of CDMA, which is central to US6611509B1 (TD-CDMA system). [cite: US6611509B1] This feature is inherent and obvious in a CDMA-based communication system.
• Claims 3, 7, 11, 15 (Separate Control and Data Time Slots): The explicit separation of the physical control channel transmission (e.g., in a "second time slot") from data transmission over a physical shared channel (e.g., in a "third time slot") is a logical application of time-division multiplexing principles (derived from US6611509B1's time-slotted nature). [cite: US6611509B1] The motivation for this separation is to avoid cross-interference and allow independent operation of control and data, leading to improved system performance and flexibility, as explicitly discussed in US11664889.
• Claims 4, 8, 12, 16 (Synchronized vs. Random Access): The distinction between using a dedicated physical control channel when a UE is time-synchronized and resorting to a random access channel when not time-synchronized is a fundamental operating principle in virtually all cellular communication systems (e.g., UMTS, as referenced in the patent). A POSITA would find it obvious to apply these standard access mechanisms in any new or evolved wireless system.

Conclusion:

The independent claims of US patent 11664889, describing a system and method for closed-loop power control using dedicated uplink and downlink physical control channels in a time-slotted, shared-channel environment, would have been obvious to a person of ordinary skill in the art by combining the teachings of US5056109A, US6611509B1, US20030069020A1, and GB2417167A. The dependent claims further elaborate on standard CDMA techniques, time-slot allocation, and network access procedures, which are also obvious design choices in such a combined system. The motivation for combining these references stems from well-known engineering principles of efficient resource management, interference mitigation, and robust power control in multi-user wireless communication systems, particularly when addressing challenges like the loss of channel reciprocity in FDD operation.