Patent Publication Number: US-2012039486-A1

Title: Wireless sound amplification system with microphone based volume control

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a wireless sound amplification system, and more particularly to a wireless sound amplification system with microphone based volume control. 
     2. Description of the Related Art 
     A conventional wireless sound amplification system includes a wireless microphone having a first amplification gain, an audio system, and a volume controller for the audio system that has a second amplification gain. While using the conventional wireless sound amplification system, such as during a speech or presentation, it may be inconvenient for the user to reach or access the volume controller to adjust the second amplification gain. The user may need to interrupt use of the wireless microphone and to obtain the assistance of another person to adjust the second amplification gain. Coordination of adjustment of the first and second amplification gains may then require multiple attempts to find satisfactory settings. Use of the conventional wireless sound amplification system may therefore by inconvenient, troublesome, and time consuming. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a wireless sound amplification system that has a wireless microphone for adjusting a second amplification gain of an audio system. 
     Another object of the present invention is to provide a volume control method for wirelessly adjusting the amplification gain of the audio system. 
     In an aspect, a wireless sound amplification system includes a wireless microphone. The wireless microphone includes an audio pickup unit for converting sound to an audio signal, an adjustment unit configured to receive an adjustment user input, and a first processing unit. The first processing unit includes a first amplifier configured to use a first amplification gain to amplify the audio signal from the audio pickup unit and to thereby generate an amplified audio signal. The first processor further includes a first controller unit configured to output a control signal based on the adjustment user input received by the adjustment unit. The first processor further includes an encoder that generates a transmission signal by encoding the amplified audio signal from the first amplifier and the control signal from the first controller unit. The wireless microphone also includes a transmitting unit for wirelessly outputting the transmission signal. 
     The audio system includes a receiving unit for receiving the transmission signal output by the transmitting unit, and a second processing unit. The second processing unit includes a decoder unit for decoding the transmission signal to recover the control signal and the amplified audio signal, and a second amplifier for receiving and amplifying the amplified audio signal using a second amplification gain. The second processing unit further includes a second controller unit for receiving the control signal and controlling the second amplification gain of the second amplifier according to the control signal. 
     In another aspect, a sound volume control method for a wireless sound amplification system that comprises a wireless microphone that includes an audio pickup unit, an adjustment unit, a first amplifier, a first controller unit, an encoder, and a transmitting unit, and an audio system that includes a second amplifier, a receiving unit, and a speaker, includes converting sound to an audio signal using the audio pickup unit of the wireless microphone. The method further includes amplifying the audio signal with a first amplification gain, using a first amplifier of the wireless microphone, to generate an amplified audio signal. The method also includes outputting a control signal from the first controller unit based on an adjustment user input received by the adjustment unit of the wireless microphone. 
     The method further includes generating a transmission signal by encoding the amplified audio signal and the control signal, and wirelessly communicating the transmission signal from the wireless microphone to the audio system. The method also includes decoding the transmission signal to recover the control signal and the amplified audio signal, and controlling a second amplification gain of the audio system according to the control signal. In addition, the method includes amplifying the amplified audio signal by the second amplification gain using a second amplifier of the audio system. 
     An advantage of the wireless sound amplification system with microphone based volume control is that a user may use the adjustment unit of the wireless microphone to generate a control signal that is wirelessly transmitted to the audio system to adjust the second amplification gain of the second amplifier of the audio system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which: 
         FIG. 1  is a perspective view of the preferred embodiment of a wireless sound amplification system according to the present invention; 
         FIG. 2  is a schematic block diagram of the wireless microphone and audio system of the preferred embodiment; 
         FIGS. 3A and 3B  are fragmentary views of the preferred embodiment in a microphone volume control mode and an audio system volume control mode; and 
         FIGS. 4A and 4B  are a flowchart illustrating operation of the preferred embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1 and 2 , the preferred embodiment of a wireless sound amplification system according to the present invention is shown to include a wireless microphone  3  and an audio system  4 . 
     The wireless microphone  3  includes an audio pickup unit  31 , a first processing unit  32  for processing the audio signal, an adjustment unit  33  configured to receive an adjustment user input and a mode user input, and a transmitting unit  34  for wireless communication of a transmission signal. The audio pickup unit  31  picks up sound waves and converts them into an audio signal for subsequent output to the first processing unit  32 . 
     The first processing unit  32  includes a first amplifier  321 , a first controller unit  322 , and an encoder  323 . The first amplifier  321  is configured to use a first amplification gain to amplify the audio signal from the audio pickup unit  31  and to generate an amplified audio signal. The first controller unit  322  is configured to output a control signal based on the adjustment user input and the mode user input received by the adjustment unit  33 . The encoder  323  generates a transmission signal by encoding the amplified audio signal from the first amplifier  321  and the control signal from the first controller unit  322 . 
     The audio system  4  has a receiving unit  41  for receiving the transmission signal from the transmitting unit  34 , a second processing unit  42  for decoding the transmission signal, and a speaker  43  to output sound. The receiving unit  41  is adapted for receiving wireless radio signals, such as the transmission signal, from the wireless microphone  3 . Given that the receiving unit  41  is not the focus of this invention, it is not further discussed. The second processing unit  42  includes a decoder unit  421  for decoding the transmission signal to recover the control signal and the amplified audio signal, a second amplifier  422  for receiving and amplifying the amplified audio signal using a second amplification gain, and a second controller  423  for receiving the control signal and controlling the second amplification gain of the second amplifier  422  according to the control signal. 
     Referring to  FIGS. 2 ,  3 A, and  32 , the adjustment unit  33  includes a function part  331  to provide a mode user input to the adjustment unit  33  and to switch the operational mode of the adjustment unit  33  between a microphone volume control mode and an audio system volume control mode. The function part  331  may include one or more knobs or keys. The adjustment unit  33  further includes a pair of display members  332  for displaying the selection result of the function part  331  and the operational mode of the adjustment unit  33 . In this embodiment, the display members  332  are a pair of light emitting diodes that respectively represent the operational modes. The display members  332  may be disposed on opposite sides of the function part  331 . 
     The adjustment unit  33  further includes a pair of operable parts  333  for providing the adjustment user input. The adjustment user input is received by the adjustment unit  33  and used to vary the first or second amplification gain in accordance with the operational mode of the adjustment unit  33 . The operable parts  333  are formed as keys, and represent incrementing the gain (using the key marked ‘+’) and decrementing the gain (using the key marked ‘−’). In variations of the preferred embodiment, the operable parts  333  may be formed as knobs disposed on opposite sides of the function key  331 . 
     As shown in  FIGS. 3A and 3B , when the function part  331  is pressed, one of the pair of display members brightens to indicate whether the operable parts  333  are operable to control either the first or the second amplification gain. In this embodiment, the display member  332  marked “M” for microphone is brightened to indicate that the first amplification gain of the first amplifier  321  may be adjusted using the pair of operable parts  333 . The other display member  332  is marked “R” for receiving amplifier of the audio system  4 , and is brightened to indicate that the second amplification gain of the second amplifier  422  may be adjusted using the pair of operable parts  333 . In this embodiment, a pair of display members  332  are used for illustration, but in variations of the preferred embodiment, one display member  332  may be used to indicate the adjusting status of the adjustment unit  33 . For example, one display member  332  may be con figured to output different flashing patterns that correspond to different operational modes of the adjustment unit  33 . 
     Referring to  FIGS. 2 ,  3 A, and  3 B, after the operational mode has been selected, the operable parts  333  can be used to increment or decrement the amplification gain that corresponds to the selected operational mode. In other words, the user can control either the first amplification gain of the first amplifier  321  or the second amplification gain of the second amplifier  422  through operation of the operable parts  333  in accordance with the selected operational mode. 
       FIGS. 4A and 4B  illustrate operation of the foregoing components of the preferred embodiment of the wireless sound amplification system. In operation S 1 , the power source of the wireless microphone  3  is turned on. After operation S 1 , in operation S 2 , the wireless sound amplification system determines whether the mode user input has been received through the function part  331  of the adjustment unit  33 . 
     In order for a user to select one of the operational modes of the adjustment unit  33 , the function part  331  may be depressed to provide the mode user input and to select either the microphone volume control mode or the audio system volume control mode. When the microphone volume control mode is selected using the function part  331 , the display marked “M” is brightened (as shown in  FIG. 3A ), and operation of the operable parts  333  increments or decrements the first amplification gain of the first amplifier  321  to amplify the audio signal to gene rate the amplified audio signal. When the audio system volume control is selected using the function part  331 , the display marked “R” is brightened (as shown in  FIG. 32 ), and operation of the operable parts  333  causes the first controller unit  322  to generate a control signal that includes or corresponds to the second amplification gain. 
     If the mode user input was not received, operation of the wireless sound amplification system proceeds to operation S 4 . If the mode user input was received, operation S 1  is followed by operation S 3 . In operation S 3 , the adjustment unit  33  is switched from one of the microphone volume control mode and the audio system volume control mode to the other one of one of the microphone volume control mode and the audio system volume control mode. Operation S 3  is followed by operation S 4 . 
     In operation S 4 , a connection is established and confirmed between the wireless microphone  3  and the audio system  4  using wireless radio signals. In operation S 5 , the wireless microphone  3  receives sound using the audio pickup unit  31 . 
     In operation S 6 , the wireless sound amplification system determines whether the adjustment user input has been received through the operable part  333  of the adjustment unit  33 . If the adjustment user input was not received, operation of the wireless sound amplification system proceeds to operation S 11 . If the adjustment user input was received, operation S 6  is followed by operation S 7 . In operation S 7 , the adjustment unit  33  is determined to be in either the microphone volume control mode or the audio system volume control mode. 
     If the adjustment unit  33  is in the microphone volume control mode, operation S 7  is followed by operation S 8 , in which the first amplification gain is adjusted according to the adjustment user input. After operation S 8 , operation of the wireless sound amplification system proceeds to operation S 11 . If the adjustment unit  33  is in the audio system volume control mode instead of the microphone volume control mode, operation S 7  is followed by operation S 9 . In operation S 9 , the first controller unit  322  outputs the control signal based on the adjustment user input received by the adjustment unit  33  of the wireless microphone  3 . After operation S 9 , in operation S 10 , the output control signal is received by the encoder  323  of the wireless microphone  3 . Operation S 10  is followed by operation S 11 . 
     In operation S 11 , the audio pickup unit  31  of the wireless microphone  3  converts the received sound into the audio signal. After operation S 11 , in operation S 12 , the audio signal is amplified by the first amplification gain. Operation S 12  is performed using the first amplifier  321  of the wireless microphone  3  to generate the amplified audio signal. After operation S 12 , in operation S 13 , the encoder  323  of the wireless microphone  3  is used to encode the transmission signal from any received input signals, which may include the amplified audio signal and the control signal. In operation S 14 , the transmission signal is wirelessly communicated from the transmitting unit  34  of the wireless microphone  3  to the receiving unit  41  of the audio system  4 . 
     In operation S 15 , the transmission signal is decoded using the decoder unit  421  of the audio system  4  to recover any encoded signals, which may include the control signal and the amplified audio signal. In operation S 16 , whether the control signal was encoded in the transmission signal is determined. If the control signal is recovered, then operation S 16  is followed by operation S 17 . Otherwise, operation S 16  is followed by operation S 18 . In operation S 17 , the second amplification gain of the audio system  4  is adjusted according to the control signal. Operation S 17  is followed by operation S 18 . In operation S 18 , the amplified audio signal is amplified by the second amplification gain using the second amplifier  422  of the audio system  4 . In operation S 19 , the output of the second amplifier  422  is output through the speaker  43 . 
     In summary, in accordance with the preferred embodiment of this invention, the user may conveniently adjust the output sound volume of the wireless sound amplifying system by using the adjustment unit  33  to select control of the gain of either the first amplifier  321  of the wireless microphone  3  or the second amplifier  422  of the audio system  4 . 
     While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation to encompass all such modifications and equivalent arrangements.