Apparatus and method for canceling interference signal in an orthogonal frequency division multiplexing system using multiple antennas

• US 20050122896A1
• Filed: 11/10/2004
• Published: 06/09/2005
• Est. Priority Date: 11/12/2003
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Dong-Jun, Hwang, Chan-Soo, Song, Kee-Bong
• Application Number:
  US10/985,515
• Publication Number:
  US 20050122896A1
• Time in Patent Office: Days
• US Class Current: 370/210
• CPC Class Codes: H04L 1/0069 Puncturing patterns
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 2001/0098 Unequal error protection

Abstract

In an encoding apparatus in a mobile communication system using a plurality of antennas, a puncturer punctures input coded bits in an RCP (Rate-Compatible Puncturing) method, a distributor divides the punctured coded bits by the number of the antennas depending on how many bits are punctured, an interleaver interleaves the divided coded bits, a modulator modulates the interleaved coded bits, and an arranger prioritizes the modulated symbols, arranges the modulated symbols according to priority levels, and transmits the arranged symbols through the antennas.

Claims

1. An encoding apparatus in a mobile communication system using a plurality of antennas, comprising:

a puncturer for puncturing input coded bits in an RCP (Rate-Compatible Puncturing) method;

a distributor for dividing the punctured coded bits by the number of antennas depending on how many bits are punctured;

an interleaver for interleaving the divided coded bits;

a modulator for modulating the interleaved coded bits;

an arranger for prioritizing the modulated symbols, arranging the modulated symbols according to priority levels, and transmitting the arranged symbols through the antennas.

2. The encoding apparatus of claim 1, wherein the arranger gives a higher priority level to a less punctured modulation symbol.

3. The encoding apparatus of claim 1, further comprising an inverse fast Fourier transformer (IFFT) for converting the modulated symbols to a frequency-domain signal, for transmission via sub-carriers on a radio channel.

4. The encoding apparatus of claim 3, wherein the puncturer punctures a different number of bits according to a coding rate.

5. A decoding apparatus in a mobile communication system using a plurality of antennas, comprising:

a fast Fourier transformer (FFT) for converting a frequency-domain signal, which is received at the antennas via sub-carriers on a radio channel, to a time-domain signal;

a successive interference cancellation (SIC) receiver for channel-estimating a lower-priority symbol using a channel estimate value of a higher-priority symbol among the FFT symbols; and

a combiner for combining the channel-estimated symbols.

6. The decoding apparatus of claim 5, wherein the SIC receiver comprises:

an arranger for determining priority levels of received symbols;

a demodulator for demodulating the higher-priority symbol into coded bits;

a deinterleaver for deinterleaving the demodulated coded bits; and

a decider for deciding transmitted bits using the deinterleaved coded bits.

7. The decoding apparatus of claim 6, wherein the SIC receiver further comprises:

an interleaver for interleaving the decided transmitted bits of the higher-priority symbol;

a modulator for modulating the interleaved coded bits; and

a minimum mean square error (MMSE) receiver for channel-estimating the lower-priority symbol using the modulated coded bits of the higher-priority symbol.

8. An encoding method in a mobile communication system using a plurality of antennas, comprising the steps of:

puncturing input coded bits in an RCP (Rate-Compatible Puncturing) method;

dividing the punctured coded bits by the number of antennas depending on how many bits are punctured;

interleaving the divided coded bits;

modulating the interleaved coded bits;

prioritizing the modulated symbols and arranging the modulated symbols according to priority levels; and

transmitting the arranged symbols through the antennas.

9. The encoding method of claim 8, wherein the prioritizing step comprises the step of giving a higher priority level to a less punctured modulation symbol.

10. The encoding method of claim 8, further comprising the step of inverse-fast-Fourier-transforming the modulated symbols to a frequency-domain signal, for transmission via sub-carriers on a radio channel.

11. The encoding method of claim 10, wherein the puncturing step comprises the step of puncturing a different number of bits according to a coding rate.

12. A decoding method in a mobile communication system using a plurality of antennas, comprising the steps of:

fast-Fourier-transforming a frequency-domain signal, which is received at the antennas via sub-carriers on a radio channel, to a time-domain signal;

channel-estimating a lower-priority symbol using a channel estimate value of a higher-priority symbol among the FFT symbols; and

combining the channel-estimated symbols.

13. The decoding method of claim 12, wherein the channel estimation step comprises the steps of:

determining priority levels of received symbols;

demodulating the higher-priority symbol into coded bits;

deinterleaving the demodulated coded bits; and

deciding transmitted bits using the deinterleaved coded bits.

14. The decoding method of claim 13, wherein the channel estimation step further comprises the steps of:

interleaving the decided transmitted bits of the higher-priority symbol;

modulating the interleaved coded bits; and

channel-estimating the lower-priority symbol using the modulated coded bits of the higher-priority symbol.