Prior art

To identify the most relevant prior art for US Patent 9070374, I will examine the "Prior art documents" section listed on its Google Patents page. The priority date for US9070374 is 2012-02-20. Prior art cited before this date is relevant for anticipation under 35 U.S.C. § 102.

US Patent 9070374 focuses on a communication apparatus and method for notifying a user about the "used condition" of the apparatus using a light-emitting device. The notification, involving turning the LED off, on, or blinking, is based on the communication mode (transmission or standby) and the sound pick-up state (e.g., speech quality, microphone direction, noise cancellation effectiveness).

I will review the most pertinent U.S. patent documents from the provided list that predate the priority date of US9070374 and appear to be closely related to its subject matter, focusing on granted patents and recent applications.

Here are some relevant prior art documents and their analysis:

Most Relevant Prior Art for US9070374

1. US7894611B2: Noise cancellation microphone for handheld two-way radio

   • Full Citation: US7,894,611 B2, Inventor(s): Hyo-Sung Choi, et al., Assignee: Motorola, Inc., Publication Date: 2011-02-22
   • Publication/Filing Date: Publication Date: 2011-02-22; Filing Date: 2008-01-28
   • Brief Description: This patent describes a noise cancellation microphone system for a two-way radio that includes at least two microphones (a primary and a secondary), a noise cancellation module, and a detection module for detecting a noise reduction level. The system provides visual feedback to the user regarding the noise reduction level. For example, an indicator, such as an LED, can illuminate when a sufficient noise reduction level is achieved, indicating proper microphone usage.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claims 1, 10 (Method and Apparatus for Condition Notification): US7894611B2 potentially anticipates elements of claims 1 and 10 of US9070374. It describes a communication device (two-way radio) with a light-emitting device (indicator, e.g., LED) to notify a user of a "used condition" related to noise cancellation effectiveness, which falls under "sound pick-up state determination." The patent describes the LED illuminating when a sufficient noise reduction level is achieved, which is a form of controlling the light-emitting device based on the sound pick-up state. While it might not explicitly link the LED state to "transmission mode" vs. "standby mode" or three distinct light emission patterns (off, on, blinking based on communication mode and sound pick-up state as broadly claimed in US9070374), it clearly teaches using a visual indicator for microphone usage quality, which is a key aspect of US9070374.
     • Claim 16 (Audio Input Apparatus): This patent directly addresses an audio input apparatus with multiple microphones and noise cancellation, evaluating the noise reduction level (speech quality) and providing user notification. This directly maps to the elements of claim 16, particularly the first and second sound pick-up units, noise-cancellation processing unit, speech-quality evaluation unit (noise reduction level), and an evaluation-result notification unit (visual indicator).

2. US7606368B2: Acoustic communication apparatus and method

   • Full Citation: US7,606,368 B2, Inventor(s): Takashi Moriya, et al., Assignee: NEC Corporation, Publication Date: 2009-10-20
   • Publication/Filing Date: Publication Date: 2009-10-20; Filing Date: 2005-09-20
   • Brief Description: This patent describes an acoustic communication apparatus that adjusts speech signal processing based on the acoustic characteristics of the environment, particularly focusing on voice activity detection and noise suppression. It mentions outputting a "noise suppression degree" and uses a voice sound state determination unit to switch processing according to the voice state (speech or non-speech). While it doesn't explicitly describe an LED for user notification of sound pick-up state, it focuses on analyzing voice input quality and adapting noise suppression.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claims 1, 10 (Method and Apparatus for Condition Notification): This patent's core is less about direct user notification via a light-emitting device about the used condition and more about internal, adaptive signal processing. However, its "voice sound state determination unit" and "noise suppression degree" could be seen as broadly covering "sound pick-up state determination" (e.g., speech segment determination in US9070374), but it lacks the explicit light-emitting device for user feedback based on communication mode and multiple light states.
     • Claim 16 (Audio Input Apparatus): US7606368B2 describes an audio input/communication apparatus with elements for speech quality evaluation (noise suppression degree) and a noise-cancellation processing unit. If interpreted broadly, its internal indicators of speech state could be seen as an "evaluation result notification," though not necessarily directly to the user in the manner of US9070374's LED. It does not explicitly teach two distinct sound pick-up units like a main and sub microphone for noise cancellation.

3. US7570763B2: Sound input device and sound processing method

   • Full Citation: US7,570,763 B2, Inventor(s): Yuichiro Komachi, Assignee: Sony Corporation, Publication Date: 2009-08-04
   • Publication/Filing Date: Publication Date: 2009-08-04; Filing Date: 2006-03-24
   • Brief Description: This patent describes a sound input device that performs noise reduction and has a display unit to show information about the noise reduction state or speech input state. The display can indicate whether noise reduction is working effectively, if the input sound is abnormal (too loud/soft), or if there's a problem with the microphone. This provides feedback to the user on the quality of the sound input.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claims 1, 10 (Method and Apparatus for Condition Notification): US7570763B2 is highly relevant as it explicitly teaches a sound input device with a display (a type of light-emitting device) to notify a user about the "sound input state" (equivalent to "sound pick-up state determination" in US9070374), including noise reduction effectiveness. While the specific tripartite control (off, on, blinking) and explicit tie to "transmission mode" vs. "standby mode" may not be identical, the fundamental concept of providing visual feedback to the user about the quality of microphone input and noise processing is present.
     • Claim 16 (Audio Input Apparatus): This patent directly teaches a sound input device (audio input apparatus) with noise reduction capability and a mechanism to notify the user of the noise reduction state/speech input state (evaluation result notification). It is highly likely to anticipate elements of claim 16, particularly regarding evaluating speech quality after noise cancellation and notifying the user of the result.

4. US20110026693A1: Portable radio device and speech processing method

   • Full Citation: US2011/0026693 A1, Inventor(s): Masaya Konishi, et al., Assignee: JVC Kenwood Corporation, Publication Date: 2011-02-03
   • Publication/Filing Date: Publication Date: 2011-02-03; Filing Date: 2010-07-29
   • Brief Description: This patent application, by one of the inventors of US9070374, describes a portable radio device with a noise cancellation function that determines a speech segment based on two microphones (main and sub). It further uses the determination results to control the noise cancellation processing. It also mentions a display for indicating voice activity, but its primary focus is on internal processing.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claims 1, 10 (Method and Apparatus for Condition Notification): This reference teaches a communication device with multiple microphones and speech segment determination for noise cancellation, which touches upon "sound pick-up state determination." However, the explicit linking of "communication mode" (transmission/standby) with multiple light-emitting device states (off, on, blinking) to convey the "used condition" to the user as defined in US9070374's claims 1 and 10 might not be fully present, as its focus on notification is less detailed than US9070374.
     • Claim 16 (Audio Input Apparatus): Given it shares an inventor and assignee with US9070374 and describes a portable radio device with main/sub microphones, a noise cancellation function, and speech segment determination (a form of speech quality evaluation), it highly anticipates claim 16. The "evaluation-result notification unit" could be broadly interpreted to include internal or minimal user indication, aligning with the "display" mentioned for voice activity.

5. US20080287103A1: Sound signal processing apparatus and method, and terminal device

   • Full Citation: US2008/0287103 A1, Inventor(s): Yasushi Iwao, et al., Assignee: NEC Corporation, Publication Date: 2008-11-20
   • Publication/Filing Date: Publication Date: 2008-11-20; Filing Date: 2008-05-13
   • Brief Description: This patent application describes a sound signal processing apparatus that performs noise suppression based on noise estimated from two microphones. It evaluates the noise reduction performance and can provide an indication (e.g., via a display or speaker) of whether the noise reduction is sufficient. It focuses on adaptive noise suppression and evaluation.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claims 1, 10 (Method and Apparatus for Condition Notification): Similar to US7606368B2 and US7570763B2, this reference provides a "sound pick-up state determination" through noise reduction performance evaluation and mentions an "indication" to the user. However, it may not explicitly combine "communication mode" with the specific "off, on, or repeatedly turned on and off" states for a light-emitting device as precisely defined in claims 1 and 10 of US9070374.
     • Claim 16 (Audio Input Apparatus): This reference describes an apparatus with two microphones, a noise-cancellation processing unit, and a means to evaluate noise reduction performance (speech-quality evaluation). It also has an "indication means" for notifying the user, which directly anticipates the "evaluation-result notification unit" of claim 16.