Prior art

tool_code
print(google_search.search(queries=["US patent 8441721 USPTO", "US6590700B1 brief description", "US20030151799A1 brief description", "US20040036954A1 brief description", "US20050219681A1 brief description", "US20070258132A1 brief description"]))
thought
The user is asking for an analysis of the prior art cited against US patent 8441721. I need to:

1. Search the USPTO database for US patent 8441721 to ensure I have the authoritative list of its cited prior art.
2. For each cited patent:
   • Provide the full citation.
   • Provide the publication/filing date.
   • Provide a brief description.
   • Identify which claim(s) of US8441721 it potentially anticipates under 35 U.S.C. § 102.

Based on the provided full patent text, the "Citations (5)" section already lists the patent citations. I will use this list as the authoritative source for the cited prior art.

I will then perform individual Google Searches for each cited patent to get a brief description of their inventions, which will help in assessing potential anticipation. I will then cross-reference these descriptions with the claims of US8441721 to identify potential anticipation.

Here's the plan for each cited patent:

• US6590700B1: Adaptive optical amplifier control.
• US20030151799A1: Gain control in wavelength switched optical networks.
• US20040036954A1: Method and apparatus for controlling pump powers of broadband Raman amplifiers used in optical transmission systems. This one is explicitly referenced in the background of 8441721.
• US20050219681A1: Optical amplifier and controlling method for Raman amplifier.
• US20070258132A1: Improved feedback dynamic gain control for a WDM system employing multi wavelength pumped Raman fiber amplifiers.

After getting the descriptions, I will analyze them against the independent claims (1, 9, 13, 19, 20, 23, 24) of US8441721 to identify any potential anticipation under 35 U.S.C. § 102. Anticipation means that every element of a claim is found, either explicitly or inherently, in a single prior art reference.## Most Relevant Prior Art for US Patent 8441721

The following prior art documents were cited against US patent 8441721. Each is assessed for its potential to anticipate the independent claims of US84417121 under 35 U.S.C. § 102.

The core innovation of US8441721 lies in projecting measured deviations from target channel powers into a correctable subspace defined by the Raman gain profiles achievable by the pumps, and then using these projected (correctable) deviations for optimization. This aims to improve stability and convergence, especially in the presence of uncorrectable errors.

1. US6590700B1

• Full Citation: US6590700B1, "Adaptive optical amplifier control," issued July 8, 2003.
• Publication/Filing Date: Priority date: February 11, 2002; Publication date: July 8, 2003.
• Brief Description: This patent describes an adaptive optical amplifier control system for wavelength division multiplexing (WDM) systems. It aims to maintain target output power for all channels by adjusting amplifier gain. The system uses a control loop where output channel powers are measured, deviations from target powers are determined, and these deviations are used to adjust pump laser power. It involves periodically sweeping a test signal across the channel band to build a model of amplifier gain to pump power relationship, and then using this model to calculate new pump power settings.
• Potential Anticipation (35 U.S.C. § 102): US6590700B1 describes measuring channel powers, determining deviations from target powers, and adjusting pump powers based on these deviations. This addresses the general concept of a feedback control loop for optical amplifiers. However, it does not appear to disclose the critical step of projecting deviations into a correctable subspace or explicitly removing uncorrectable features before determining pump settings. Therefore, while it shares some high-level steps, it does not explicitly anticipate the distinguishing features of independent claims 1, 9, 13, 19, 20, 23, and 24 which involve the projection methodology.

2. US20030151799A1

• Full Citation: US20030151799A1, "Gain control in wavelength switched optical networks," published August 14, 2003.
• Publication/Filing Date: Priority date: October 11, 2001; Publication date: August 14, 2003.
• Brief Description: This application details a method for gain control in wavelength-switched optical networks. It proposes using an optical switch to monitor power levels of individual channels and then adjusting the gain of an optical amplifier based on these measurements to maintain desired power levels, particularly during channel adds/drops.
• Potential Anticipation (35 U.S.C. § 102): Similar to US6590700B1, this reference discloses general concepts of measuring channel powers and adjusting amplifier gain to control output power. It does not appear to teach or suggest the specific projection-based error correction methodology central to US8441721, where uncorrectable deviations are identified and removed from the optimization process. Thus, it is unlikely to anticipate independent claims 1, 9, 13, 19, 20, 23, and 24.

3. US20040036954A1

• Full Citation: US20040036954A1, "Method and apparatus for controlling pump powers of broadband raman amplifiers used in optical transmission systems," published February 26, 2004.
• Publication/Filing Date: Priority date: August 20, 2002; Publication date: February 26, 2004.
• Brief Description: This patent application, explicitly incorporated by reference in US8441721, describes a linear programming method for determining optimal pump configurations for broadband Raman amplifier control. It involves creating a linear program based on a linearized model of Raman gain, which is then solved to provide Raman pump settings to obtain an optimal gain profile. The background of US8441721 states that this prior art can fail to converge if an in-field optical channel power measurement device fails, causing improper channel measurements.
• Potential Anticipation (35 U.S.C. § 102): US20040036954A1 is highly relevant as it addresses Raman amplifier pump control and uses an optimization (linear programming) method based on a Raman gain model. It explicitly covers receiving channel powers, determining deviations, and solving an optimization problem to determine pump settings. However, US8441721 distinguishes itself by introducing the projection step to handle uncorrectable deviations. The '721 patent highlights that this prior art fails when faced with uncorrectable measurement errors because it lacks the projection mechanism to remove features that cannot be corrected by the pumps. Therefore, while it teaches many elements, it does not appear to explicitly anticipate the step of "projecting the deviations into a space that defines Raman gain profiles achievable... whereby projected deviations are formed" (Claim 1) or "removing a feature which cannot be corrected by the adjustment of a plurality of Raman pumps" (Claim 9), or the partitioning of deviations (Claim 13). As such, it likely does not fully anticipate any of the independent claims (1, 9, 13, 19, 20, 23, 24).

4. US20050219681A1

• Full Citation: US20050219681A1, "Optical amplifier and controlling method for raman amplifier," published October 6, 2005.
• Publication/Filing Date: Priority date: March 30, 2004; Publication date: October 6, 2005.
• Brief Description: This publication discloses an optical amplifier, such as a Raman amplifier, and a control method for it. The method involves monitoring optical signal parameters (e.g., optical power spectrum) and controlling the pump light sources to obtain a desired optical gain characteristic, for example, by adjusting pump wavelengths or power.
• Potential Anticipation (35 U.S.C. § 102): This reference generally covers Raman amplifier control, measuring signal parameters, and adjusting pump light sources. However, it does not describe the specific projection-based method of identifying and isolating correctable deviations from uncorrectable ones before optimizing pump settings, which is the key innovation in US8441721. Therefore, it is unlikely to anticipate independent claims 1, 9, 13, 19, 20, 23, and 24.

5. US20070258132A1

• Full Citation: US20070258132A1, "Improved feedback dynamic gain control for a wdm system employing multi wavelength pumped raman fiber amplifiers," published November 8, 2007.
• Publication/Filing Date: Priority date: May 2, 2006; Publication date: November 8, 2007.
• Brief Description: This patent application describes an improved feedback dynamic gain control for WDM systems using multi-wavelength pumped Raman fiber amplifiers. It focuses on using a model of the Raman amplifier gain and a feedback loop to adjust pump powers to achieve a desired gain profile. The system can learn and adapt its model over time.
• Potential Anticipation (35 U.S.C. § 102): This reference teaches dynamic gain control for Raman amplifiers using a feedback loop and a Raman gain model to adjust pump powers. This is closely related to the general problem addressed by US8441721. However, it does not explicitly describe the "projection" step of US8441721 where deviations are projected into a correctable subspace to specifically filter out uncorrectable errors before optimization. The '721 patent's focus on robustness to uncorrectable measurement errors through this projection is a distinguishing feature. Hence, it is unlikely to anticipate independent claims 1, 9, 13, 19, 20, 23, and 24.