Noise reducing apparatus for minimizing noise in modems

• US 6,674,809 B1
• Filed: 05/23/2000
• Issued: 01/06/2004
• Est. Priority Date: 05/27/1999
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Kay, Shin-woong
• Primary Examiner(s): TSE, YOUNG TOI
• Application Number:
  US09/577,362
• Time in Patent Office: 1,323 Days
• Field of Search: 375/219, 375/220, 375/222, 375/285, 375/296, 455/63.1, 455/63.3, 725/111, 725/124
• US Class Current: 375/285
• CPC Class Codes: H04B 15/02 Reducing interference from electric apparatus by means located at or near the interfering apparatus
• CPC Class Codes: H04L 27/00 Modulated-carrier systems

Abstract

A noise reducing apparatus for minimizing spurious noise in a system utilizing a cable modem is provided. The noise reducing apparatus for reducing a noise generated according to operation of a modem includes a controlling unit for controlling the modem and producing an enable signal according to generation of the noise, a programmable gain controller for turning on/off a transmission level in response to the enable signal of the controlling unit, a noise removing unit for removing predetermined noise generated by the programmable gain controller when the modem does not transmit a signal, and a tuner for tuning the output of the noise removing unit to connect it to a coaxial cable network. Since a circuit comprised of gates and gallium arsenide integrated circuit single-pole double-throw switches is employed therein to minimize spurious noise when a cable modem does not transmit a signal, the quality in the communication between a cable modem and a headend can be ensured.

Claims

1. A noise reducing apparatus for reducing noise according to an operation of a modem, said noise reducing apparatus comprising:

a controlling unit for controlling said modem and producing an enable signal according to generation of said noise;

a gain controller for controlling an on/off state of a transmission level in response to said enable signal generated by said controlling unit;

a noise removing unit for removing predetermined noise which is generated by said transmission level of said gain controller when said modem is not transmitting a signal; and

a tuner for tuning the output of said noise removing unit to a coaxial cable network.

2. The apparatus of claim 1, wherein-said noise removing unit comprises:

a first inverter for inverting the enable signal of said controlling unit;

a second inverter for inverting output of said first inverter;

a first switch for inputting outputs of said first and said second inverters to switch output of said gain controller;

a packet assembler/dissembler for setting a first output of said first switch as a predetermined gain; and

a second switch for inputting outputs of said first and said second inverters to switch output of said packet assembler/dissembleer and a second output of said first switch.