Infrared signal communication system and method including transmission means having automatic gain control

• US 6,590,682 B1
• Filed: 08/10/1998
• Issued: 07/08/2003
• Est. Priority Date: 08/10/1998
• Status: Expired due to Term

• Current Assignee: IXYS Intl Limited (Littelfuse Incorporated)
• Original Assignee: ZiLOG Incorporated (Littelfuse Incorporated)
• Inventors: Hamilton, T Allan
• Primary Examiner(s): NEGASH, KINFE MICHAEL
• Application Number:
  US09/131,825
• Time in Patent Office: 1,793 Days
• Field of Search: 359/142-143, 359/152-153, 359/171, 359/172, 359/187, 455/69, 455/88, 455/522
• US Class Current: 398/139
• CPC Class Codes: H04B 10/1143 Bidirectional transmission

Abstract

An Improved Infrared Signal Communication System and Method Including Transmission Means Having Automatic Gain Control is disclosed. Also disclosed is system and method that adjusts signal transmission power in response to incident signal power amplitude. The preferred system includes a control signal loop within the signal receiving system, and the system further includes a signal transmitting system that is responsive to the control signal loop. The preferred system includes manual, semi-automatic and automatic modes of operation. Still further, the preferred method includes at least two Ir-enabled appliances “stepping” each other “down” in transmit power in response to directives issued by the other Ir-enabled appliance.

Claims

1. An infrared radiation signal transmitting and receiving unit, comprising:

an infrared radiation transmitter,

a transmitter circuit receiving data to be transmitted, and including a driver of the infrared radiation transmitter that includes the data in an infrared radiation signal emitted from the radiation transmitter,

an infrared radiation receiver,

a receiver circuit including an automatic gain control connected to receive a data carrying output of the infrared radiation receiver, generate a signal representative of the strength of the infrared signal received by the radiation receiver and provide the data carrying output with a gain adjusted level in response to said infrared signal strength signal,

the transmitter driver being responsive to said infrared signal strength signal for controlling the level of power imparted to the infrared radiation signal emitted by the radiation transmitter,

wherein the receiver circuit automatic gain control includes a variable gain amplifier connected to the infrared radiation receiver and a comparator connected to an output of the amplifier, wherein the signal representative of the strength of the infrared signal received by the radiation receiver is an output of the comparator that is connected to control the gain of the variable gain amplifier, and

wherein the transmitter driver includes an amplifier that also receives the signal representative of the strength of the infrared signal received by the radiation receiver for controlling the power imparted to the infrared radiation signal emitted by the radiation transmitter.