Obviousness

Obviousness Analysis of US Patent 9,769,776

Introduction

This analysis examines the obviousness of US Patent 9,769,776, titled "Apparatus and method for uplink synchronizing in a multiple component carrier system," under 35 U.S.C. § 103. The analysis is based on a review of the patent's claims and the prior art cited during its prosecution. A person having ordinary skill in the art (a "POSA") at the time of the invention would have been a wireless communication engineer with experience in 3GPP LTE standards, particularly in the areas of radio resource control (RRC), medium access control (MAC), and physical layer procedures related to carrier aggregation and uplink synchronization.

Summary of the Invention

US Patent 9,769,776 describes a method and apparatus for managing Timing Advance Groups (TAGs) in a wireless communication system that uses multiple component carriers (i.e., carrier aggregation). A TAG is a group of serving cells that share the same timing advance value, which is crucial for maintaining uplink synchronization. The invention focuses on the process of reorganizing TAGs when a secondary serving cell (SCell) is added or removed. The key aspects of the invention involve:

• A user equipment (UE) receiving secondary serving cell (SCell) configuration information from a base station (eNB).
• This configuration information includes a first field to indicate the removal of an SCell and a second field to indicate the addition of an SCell and its associated TAG ID.
• The UE first performs the removal of the specified SCell and then the addition of the new SCell.
• The UE then reorganizes its TAG configuration based on the received information, including the newly added SCell in the specified TAG.

Prior Art References

The following prior art references were cited during the prosecution of US Patent 9,769,776 and are relevant to the obviousness analysis:

• US 2012/0069810 A1 ("Bakshi"): This reference discloses a method for managing multiple timing advances in a carrier aggregation system. It teaches the concept of grouping cells into timing alignment groups and using RRC signaling to configure these groups.
• US 2013/0044697 A1 ("Ishii"): Ishii describes a method for configuring and activating SCells in a carrier aggregation system. It details the use of RRC messages to add and release SCells.
• 3GPP TS 36.331 V10.5.0 (2012-03): This technical specification from the 3rd Generation Partnership Project (3GPP) defines the Radio Resource Control (RRC) protocol for the E-UTRAN (LTE) interface. It specifies the structure and content of RRC messages, including those for configuring SCells and other radio resources.

Obviousness Combination of Prior Art

The claims of US Patent 9,769,776 would have been obvious to a POSA by combining the teachings of Bakshi, Ishii, and the 3GPP TS 36.331 specification.

Detailed Analysis

The independent claims of the '776 patent generally recite a method and a UE for reorganizing a TAG by receiving SCell configuration information that includes fields for both removing and adding SCells, and then performing these actions sequentially.

1. Motivation to Combine: A POSA at the time of the invention would have been motivated to combine the teachings of Bakshi, Ishii, and the 3GPP standards to arrive at the claimed invention. The development of carrier aggregation in LTE was a major focus, and efficient management of SCells and their associated timing was a known problem. Bakshi establishes the concept of TAGs and their configuration via RRC signaling. Ishii provides details on the RRC procedures for adding and releasing SCells. The 3GPP TS 36.331 specification provides the standardized framework and message structures for these RRC procedures. A POSA, tasked with implementing a robust and efficient mechanism for SCell management, would have naturally looked to the existing RRC framework to handle both the addition and removal of SCells in a coordinated manner. It would have been a logical and predictable step to include parameters for both adding and removing SCells within a single RRC connection reconfiguration message to streamline the process and reduce signaling overhead.

2. Element-by-Element Analysis of an Exemplary Independent Claim:

   • "A user equipment (UE) of re-organizing a timing advance group (TAG), the UE comprising: a receiving unit for receiving, from a serving base station, secondary serving cell (SCell) configuration information which includes a first field and a second field, the first field including an ScellIndex of an SCell to indicate a removal of the SCell, the second field including at least one of the ScellIndex to indicate an addition of the SCell and a TAG ID indicating a TAG of the SCell...":

     • Bakshi teaches the concept of TAGs and the use of RRC signaling to configure them.
     • Ishii discloses the use of RRC messages to add and release SCells, which would inherently include an index (ScellIndex) to identify the specific SCell.
     • The 3GPP TS 36.331 specification defines the RRCConnectionReconfiguration message, which is the standard vehicle for conveying such configuration changes. A POSA would have found it obvious to include fields for both sCellToReleaseList (the first field) and sCellToAddModList (the second field) within this single message for efficient SCell management. The inclusion of a tag-Id within the SCell addition configuration is a direct and logical extension of Bakshi's teaching of configuring TAGs via RRC signaling.

   • "...and a radio resource control (RRC) processing unit for performing the addition of the SCell after performing the removal of the SCell from one or more SCells configured in the UE, and for reorganizing the TAG by including the SCell in the TAG.":

     • This element describes the sequential processing of the removal and addition operations by the UE's RRC processing unit. This is a standard and predictable implementation detail for processing a configuration message with multiple instructions. A POSA would understand that to maintain a consistent state, the removal of an old configuration should precede the addition of a new one. The reorganization of the TAG is the direct and intended consequence of the received configuration information, as taught by Bakshi. The UE's action of including the new SCell in the specified TAG is the explicit instruction carried in the RRC message.

Conclusion

In conclusion, the claims of US Patent 9,769,776 would have been obvious to a person of ordinary skill in the art at the time of the invention. The combination of the teachings from Bakshi, Ishii, and the 3GPP TS 36.331 specification discloses all the elements of the claimed invention. The motivation to combine these references would have been driven by the need for an efficient and standardized method for managing SCell configurations and their associated timing advance groups within the evolving LTE carrier aggregation framework. The claimed solution represents a predictable and logical extension of the existing technologies and standards.