Digital iterative gain control

• US 7,822,349 B2
• Filed: 07/30/2003
• Issued: 10/26/2010
• Est. Priority Date: 08/01/2002
• Status: Active Grant

• Current Assignee: Inncom Intl Inc (Honeywell International Inc.)
• Original Assignee: Inncom Intl Inc (Honeywell International Inc.)
• Inventors: Roosli, Philipp, Shah, Hazrat, Giffone, Ralph
• Primary Examiner(s): Phan; Hanh
• Application Number:
  US10/631,457
• Publication Number:
  US 20040022334A1
• Time in Patent Office: 2,645 Days
• Field of Search: 398/202, 398/209, 398/210, 398/208, 398/127, 398/128, 398/130, 398/135, 398/136, 398/137, 398/138, 398/25, 398/26, 398/27, 375/345, 375/316, 375/317, 375/318, 375/295, 250/214.A, 250/214.B, 250/214.AG, 250/214.R, 250/214.C, 250/214.LA, 330/308, 330/59
• US Class Current: 398/202
• CPC Class Codes: H03G 3/3084 in receivers or transmitters for electromagnetic waves other than radiowaves, e.g. lightwaves H03G3/32, H03G3/34 take precedence
• CPC Class Codes: H04B 10/114 Indoor or close-range type systems

Abstract

In an IR communication network, a method is described to optimize channel performance in the presence of strong and varying IR interference. The method controls of the channel gain based on quantitative measurement of the channel noise.

Claims

1. A wireless communication system comprising

a transmitter;

and

a receiver;

the receiver having a digitally controllable gain;

the gain being iteratively adjusted based on a combination of reception noise, correctly received data packets, and quiet reception intervals.

2. The communication system of claim 1, where a communication channel uses IR.

3. The communication system of claim 1, where the gain is iteratively adjusted until a preset level of noise is received in a predetermined unit of time and where the reception noise is primarily shot noise.

4. The communication system of claim 3, where the preset level of noise is a number of noise pulses per second.

5. The communication system of claim 3, where a sampling period for noise pulses is longer than the length of a data packet.

6. The communication system of claim 1, where adjustment of the gain is linked to an external event.

7. The communication system of claim 1, where the receiver separates noise from data based on validity of decoded data packets.

8. The communication system of claim 1, where the gain of the receiver is attenuated to measure a margin of signal that is available.

9. A wireless communication system, comprising

a transmitter from which a transmitter signal is transmittable;

and

a receiver which is configured to receive multiple signals and noise and to operate during otherwise quiet periods when no signals or noise is received, wherein,

in an event a received one of the multiple signals is reflective of the transmitter signal or a current period is quiet, a sensitivity of a gain of the receiver is increased, and,

in an event the received one of the multiple signals is not reflective of the transmitter signal or the receiver is receptive of the noise, the sensitivity is decreased.

10. The wireless communication system according to claim 9, wherein the transmitter signal comprises a data packet.

11. The wireless communication system according to claim 9, wherein the gain is digitally controllable.

12. The wireless communication system according to claim 9, wherein the sensitivity is increased/decreased by a corresponding increase/decrease in a gain adjustment interval.

13. A wireless communication system, comprising

a transmitter from which a transmitter signal is transmittable;

a receiver which is configured to receive multiple signals and noise and to operate during otherwise quiet periods when no signals or noise is received; and

a microprocessor coupled to the receiver to determine whether a received one of the multiple signals is reflective of the transmitter signal, whether a current period is quiet and whether the receiver is receptive of the noise, to increase a sensitivity of a gain of the receiver if the received one signal is reflective of the transmitter signal or the current period is quiet, and to decrease the sensitivity if the received one signal is not reflective of the transmitter signal or the receiver is receptive of the noise.