Method of compensating signal distortion of one-tap equalizer bank for the orthogonal frequency division multiplexing system

• US 20020167997A1
• Filed: 07/13/2001
• Published: 11/14/2002
• Est. Priority Date: 02/07/2001
• Status: Abandoned Application

• Current Assignee: Kwangju Institute Of Science And Technology
• Original Assignee: Kwangju Institutes of Science and Technology
• Inventors: Kang, Hong Ku, Kim, Ki Seon
• Application Number:
  US09/903,527
• Publication Number:
  US 20020167997A1
• Time in Patent Office: Days
• US Class Current: 375/229
• CPC Class Codes: H03H 21/0012 Digital adaptive filters
• CPC Class Codes: H04L 2025/03414 Multicarrier
• CPC Class Codes: H04L 2025/03522 Frequency domain
• CPC Class Codes: H04L 25/03159 operating in the frequency domain H04L25/03165, H04L25/03178 take precedence

Abstract

The present invention relates to an orthogonal frequency division multiplexing(OFDM) system.

The present invention presents a method of compensating the subcarrier signal distortion in an OFDM system caused by multi-path fading channels by using one-tap equalizer bank, which compensates the signal distortion with remarkably reduced system complexity compared with the prior art by introducing simplified calculation procedures of calculating a tap-value of an equalizer for one subcarrier using the tap-values of the equalizers for adjacent subcarriers.

Claims

1. A method of compensating signal distortion of one-tap equalizer bank for an orthogonal frequency division multiplexing(OFDM) system, which compensates the subcarrier signal distortion in an OFDM system caused by multi-path fading channels by using one-tap equalizer bank, characterized by:

compensating the signal distortion by calculating a tap-value of an equalizer for one subcarrier using the tap-values of the equalizers for adjacent subcarriers.

2. A method of compensating signal distortion of one-tap equalizer bank for an OFDM system as claimed in claim 1,

wherein said tap-value of an equalizer is calculated by the following equation:

C_k=ƒ

(C<sub>k−

1</sub>, C<sub>k−

1</sub>), 

 

Equation 6

 

where, C_k is tap-value of an equalizer for k-th subcarrier.

3. A method of compensating signal distortion of one-tap equalizer bank for an OFDM system as claimed in claim 1 or 2,

wherein said tap-value of an equalizer is calculated by a linear interpolation method expressed by the following equation:

$\begin{array}{cc}{C}_k=\frac{C_{k-1}+C_{k+1}}{2},& \left[\mathrm{Equation}<br><br>\text{\hspace{1em}<br><br>}<br><br>7\right]\end{array}$

 

where, C_k is tap-value of an equalizer for k-th subcarrier.

4. A method of compensating signal distortion of one-tap equalizer bank for an OEDM system as claimed in claim 3,

wherein said linear interpolation method is characterized in that:

addition is carried out by a full-adder; and

division is carried out by a wired shift operation, which moves the output of the full adder to 1-bit to the right.