Apparatus for receiving satellite broadcasting and method thereof

• US 7,865,135 B2
• Filed: 08/16/2006
• Issued: 01/04/2011
• Est. Priority Date: 08/18/2005
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Park, Kwang Jae
• Primary Examiner(s): Urban; Edward
• Assistant Examiner(s): Sorowar; Golam
• Application Number:
  US11/909,849
• Publication Number:
  US 20080216128A1
• Time in Patent Office: 1,602 Days
• Field of Search: 455/3.02, 375/350, 725/68
• US Class Current: 455/3.02
• CPC Class Codes: H04B 1/30 for homodyne or synchrodyne receivers demodulator circuits H03D1/22

Abstract

A method for receiving satellite broadcasting includes: amplifying an inputted satellite broadcasting signal; converting the amplified signal to a baseband signal by mixing the amplified signal with a center frequency of a selected channel; and varying a channel bandwidth of the baseband signal.

Claims

1. An apparatus for receiving satellite broadcasting, comprising:

a radio frequency (RF) input unit for amplifying an inputted satellite broadcasting signal;

a local oscillator for outputting a center frequency of a selected channel;

a mixer for converting an output signal of the RF input unit into a baseband signal by mixing the output signal with the center frequency of the local oscillator; and

a bandwidth controller for varying a bandwidth of each channel using a bandwidth (BW) obtained using the following equation;

BW=(1+α

)×

SR/log₂M+F_Receiver,

where α

represents a roll off factor, SR represents a symbol rate. M represents a degree of modulation, and F_Receiver represents a drift amount of a channel frequency.

2. The apparatus according to claim 1, wherein the bandwidth controller comprises:

a channel information detecting module for detecting a symbol rate and a reference center frequency of the selected channel;

a bandwidth determining module for determining the bandwidth using the equation; and

a bandwidth varying module for varying a channel bandwidth of the baseband signal to a bandwidth determined by the bandwidth determining module.

3. The apparatus according to claim 1, wherein the drift amount of the channel frequency is a difference between the reference center frequency of the channel and an actually-tuned center frequency.

4. The apparatus according to claim 1, wherein the inputted satellite broadcasting signal is provided by an antenna unit, wherein the antenna unit comprises:

an antenna for receiving a C band or a Ku band from a satellite; and

a low noise block (LNB) for down-converting a signal received by the antenna to an intermediate frequency, and outputting the down-converted signal to the RF input unit.

5. A method for receiving satellite broadcasting, the method comprising:

amplifying an inputted satellite broadcasting signal;

converting the amplified signal to a baseband signal by mixing the amplified signal with a center frequency of a selected channel; and

varying a channel bandwidth of a selected channel using the following equation;

BW=(1+α

)×

SR/log₂M+F_Receiver,

where α

represents a roll off factor, SR represents a symbol rate, M represents a degree of modulation, and F_Receiver represents a drift amount of a channel frequency.

6. The method according to claim 5, further comprising converting the inputted satellite broadcasting signal into an intermediate frequency by a low noise block (LNB) of an antenna unit before amplifying the inputted satellite broadcasting signal.