Title:
ワイヤレスマイクロホン用受信装置
Document Type and Number:
Japanese Patent JP4236335
Kind Code:
B2
Abstract:
There is provided an improved receiver unit for wireless microphone system. The receiver unit accomplishes desirable mute control in accordance with state transmitting conditions of electric wave from a wireless microphone. The receiver unit includes a receiver device 12 for receiving electric wave, a detector circuit 13, and tone and noise signals detection circuits 16, 15 for detecting a signal level (field intensity), and tone and noise signals of the electric wave, respectively, each of the signal level and the signals being used as parameter signals for detecting received state of the electric wave, a mute circuit which is controlled in accordance with the detected, received state of the electric wave that is detected from one of the parameter signals, A/D converters 191 to 193 for converting the parameter signals from analog signal into digital signal, respectively, and a controller 20 having a threshold to be set with respect to the parameter signal, the controller switching on/off the mute circuit in accordance with difference between the parameter signal and threshold. The controller 20 has a first period of time that is previously set in accordance with threshold, as timing in switching off said mute circuit and a second period of time during which period the parameter signal of the received electric wave reaches the threshold. The mute circuit 17 is switched off or on at variable interval in accordance with the difference between the first period of time and second period of time.
Inventors:
Niwamoto
Application Number:
JP15590399A
Publication Date:
March 11, 2009
Filing Date:
June 03, 1999
Export Citation:
Assignee:
Audio Technica Co., Ltd.
International Classes:
H04B1/10; H04R3/00; H03G3/34
Domestic Patent References:
| JP5114870A | ||||
| JP7025633U | ||||
| JP8279740A | ||||
| JP57011539A | ||||
| JP10308678A |
Attorney, Agent or Firm:
Takuya Ohara