Prior art

To identify the most relevant prior art for US patent 7548592, I will search the USPTO database for the patent and examine its cited references. Prior art includes information publicly known before the effective filing date of the claimed invention, which can encompass U.S. and foreign patents and published patent applications, as well as non-patent literature. For each cited patent, I'll extract its full citation, publication/filing date, a brief description of its subject matter, and analyze which claims of US7548592 it potentially anticipates under 35 U.S.C. § 102.

Prior Art for US Patent 7548592

A search of US Patent 7548592 reveals the following prior art citations:

• U.S. Patent 6,101,224 (Issued August 8, 2000) - "Method and apparatus for multiple input, multiple output (MIMO) wireless communication systems"

  • Inventors: Paul W. Wolniansky, et al.
  • Publication/Filing Date: Filed July 2, 1999; Issued August 8, 2000.
  • Description: This patent describes a MIMO wireless communication system that utilizes multiple transmit and receive antennas to increase data throughput and spectral efficiency. It focuses on transmitting multiple data streams simultaneously over the same frequency channel and employs spatial processing at both the transmitter and receiver to separate these streams. The patent discusses techniques for channel estimation and for generating transmit and receive weight vectors to optimize signal reception.
  • Potential Anticipation of Claims: This patent potentially anticipates aspects of independent claims 1, 9, and 16 of US7548592, particularly regarding the fundamental concept of using multiple inputs and outputs in a wireless communication system to transmit and receive signals with weighting. Specifically, the idea of weighting signals at both the transmitter and receiver to manage multiple data streams is a core concept here.

• U.S. Patent 6,185,258 (Issued February 6, 2001) - "Space-time coding for wireless communications"

  • Inventors: Vafa Ahmadi, et al.
  • Publication/Filing Date: Filed December 29, 1998; Issued February 6, 2001.
  • Description: This patent describes space-time coding techniques for wireless communication systems that use multiple transmit antennas. It aims to improve reliability and data rate by introducing redundancy across multiple antennas and time. While focused on coding, the underlying principle involves manipulating signals across multiple transmit antennas, which relates to the weighting concepts in US7548592.
  • Potential Anticipation of Claims: This patent could potentially anticipate elements within claims 1 and 9 of US7548592 that pertain to the use of multiple transmit antennas and the manipulation of signals transmitted from them, although the specific weighting and decomposition techniques in US7548592 for signal decoupling and equal signal strength might differentiate it.

• U.S. Patent 6,363,101 (Issued March 26, 2002) - "Apparatus and method for multiple input, multiple output (MIMO) wireless communication systems"

  • Inventors: Paul W. Wolniansky, et al.
  • Publication/Filing Date: Filed August 9, 2000; Issued March 26, 2002.
  • Description: A continuation of U.S. Patent 6,101,224, this patent further details a MIMO system that uses multiple antennas at both the transmitter and receiver. It focuses on methods for calculating and applying channel-dependent weights to the transmitted and received signals to enable the transmission of multiple independent data streams and improve overall system performance.
  • Potential Anticipation of Claims: This patent strongly anticipates claims 1, 9, and 16 of US7548592 due to its explicit focus on methods and apparatus for weighting signals in a MIMO system to enable independent data streams. The description of calculating and applying weights directly relates to the core inventive concepts of US7548592.

• U.S. Patent 6,430,223 (Issued August 6, 2002) - "Adaptive array antenna for wireless communication"

  • Inventors: K. C. Chen, et al.
  • Publication/Filing Date: Filed December 15, 1999; Issued August 6, 2002.
  • Description: This patent describes an adaptive array antenna system for wireless communication that uses beamforming techniques to improve signal quality and capacity. It involves adjusting weights to optimize the radiation pattern, which is a foundational aspect of MIMO systems that aim to manage signal paths.
  • Potential Anticipation of Claims: This patent potentially anticipates the general concept of applying weights to signals transmitted or received by antenna arrays as described in claims 1 and 9. However, the specific decomposition and optimization goals of US7548592 (e.g., equal signal strength at the receiver, orthogonal weighting vectors) may distinguish it from the broader adaptive array antenna teachings.

• U.S. Patent 6,553,080 (Issued April 22, 2003) - "Method and apparatus for multiple input, multiple output (MIMO) wireless communication systems with a time varying channel"

  • Inventors: Paul W. Wolniansky, et al.
  • Publication/Filing Date: Filed January 16, 2001; Issued April 22, 2003.
  • Description: Another continuation of U.S. Patent 6,101,224, this patent specifically addresses MIMO systems operating in time-varying channels. It describes methods for adapting the transmit and receive weights to maintain performance as the channel characteristics change over time.
  • Potential Anticipation of Claims: This patent significantly anticipates claims 1, 9, and 16 of US7548592, especially in the context of handling dynamic channel conditions and using adaptable weighting techniques in MIMO systems. The emphasis on managing time-varying channels further refines the concept of signal weighting and optimization.

• U.S. Patent 6,647,065 (Issued November 11, 2003) - "MIMO system with channel estimation and beamforming"

  • Inventors: Howard C. Yang, et al.
  • Publication/Filing Date: Filed December 14, 2000; Issued November 11, 2003.
  • Description: This patent describes a MIMO system that performs channel estimation and applies beamforming techniques. It details how channel state information is acquired and used to generate transmit and receive weights for beamforming, aiming to improve signal-to-interference-plus-noise ratio (SINR).
  • Potential Anticipation of Claims: This patent could anticipate aspects of claims 1, 9, and 16, particularly the use of channel estimation to derive weighting coefficients. The general concept of beamforming through weighting in a MIMO system is present, but the specific decomposition methods and optimization goals of US7548592 (e.g., AUMD, equal SNR, orthonormal V matrix) would be key for differentiation.

• U.S. Patent 6,765,972 (Issued July 20, 2004) - "MIMO wireless communication system with improved channel capacity"

  • Inventors: Paul W. Wolniansky, et al.
  • Publication/Filing Date: Filed November 14, 2002; Issued July 20, 2004.
  • Description: Another in the series from Wolniansky, et al., this patent focuses on maximizing channel capacity in MIMO systems. It describes advanced signal processing techniques for determining optimal transmit and receive filters (weights) based on the channel matrix to achieve higher data rates.
  • Potential Anticipation of Claims: This patent strongly anticipates claims 1, 9, and 16 of US7548592, as it deals directly with optimizing transmit and receive weights to improve channel capacity in MIMO systems, which is a central theme of US7548592. The techniques for determining optimal filters (weights) are highly relevant.

• U.S. Patent Application Publication 2003/0072382 A1 (Published April 17, 2003) - "Multiple input, multiple output communications systems"

  • Inventors: James S. Wight (the same inventor as US7548592)
  • Publication/Filing Date: Filed October 10, 2002; Published April 17, 2003.
  • Description: This is a patent application by the same inventor and is a predecessor to US7548592. It describes similar concepts for optimizing transmitter and receiver weights in MIMO systems, including creating beam nulls, achieving equivalent signal strength, and using decomposition techniques.
  • Potential Anticipation of Claims: As this is an earlier publication by the same inventor covering very similar subject matter, it is highly likely to anticipate all claims (1, 9, and 16) of US7548592 under 35 U.S.C. § 102 as it would represent the inventor's own prior disclosure if the filing date of US7548592 is later than the effective filing date of this application. It would certainly be relevant for obviousness if not direct anticipation.

• U.S. Patent Application Publication 2004/0022320 A1 (Published February 5, 2004) - "Multiple input, multiple output (MIMO) system and method for reducing interference"

  • Inventors: Ayman F. Naguib, et al.
  • Publication/Filing Date: Filed July 17, 2002; Published February 5, 2004.
  • Description: This publication describes a MIMO system and method for reducing interference between multiple data streams. It employs spatial processing at the transmitter and/or receiver to minimize interference and improve signal quality, potentially through techniques like zero-forcing or other interference cancellation methods.
  • Potential Anticipation of Claims: This patent publication potentially anticipates aspects of claims 1, 9, and 16 related to minimizing interference between signals in a MIMO system through weighting. The specific methods for achieving this (e.g., "create and steer beam nulls, such that each transmitted signal is substantially decoupled from all other transmitted signals" as stated in US7548592's abstract) would need careful comparison.

• U.S. Patent Application Publication 2004/0120410 A1 (Published June 24, 2004) - "Multiple-input multiple-output systems with improved performance"

  • Inventors: Vafa Ahmadi, et al.
  • Publication/Filing Date: Filed December 23, 2002; Published June 24, 2004.
  • Description: This publication presents MIMO systems designed for improved performance, potentially through advanced signal processing, coding, or antenna configuration. It aims to enhance data rates, reliability, or spectral efficiency.
  • Potential Anticipation of Claims: This patent publication may anticipate general system aspects of claims 1 and 9 related to MIMO systems with improved performance. The specifics of the "improved performance" and the techniques used would determine the extent of anticipation of US7548592's claims.

It is important to note that the ultimate determination of anticipation under 35 U.S.C. § 102 requires a detailed claim-by-claim analysis against the full disclosure of each prior art reference. This overview provides a preliminary assessment of the potential relevance based on titles and abstracts.