Method and apparatus for generating ranging preamble code in wireless communication system

Patent metadata

Field	Value
Publication number	US-9019811-B2
Application number	US-90977610-A
Country	US
Kind code	B2
Filing date	Oct 21, 2010
Priority date	Nov 5, 2009
Publication date	Apr 28, 2015
Grant date	Apr 28, 2015

Abstract

A method and apparatus of generating a ranging preamble code in a wireless communication system comprises generating a Zadoff-Chu (ZC) sequence in which a cyclic shift is applied to each of a plurality of orthogonal frequency division multiple access (OFDMA) symbols as a ranging preamble code, wherein the cyclic shift is applied for each OFDMA symbol.

First claim

What is claimed is:

1. A method of generating a ranging preamble code in a wireless communication system, the method comprising: determining by a hardware processor a cyclic shift using a cyclic shift unit in a time domain, the cyclic shift unit determined using a Fast Fourier Transform (FFT) size that is 512, 1024 or 2048 based on a bandwidth; generating a Zadoff-Chu (ZC) sequence in which the cyclic shift is applied for each of a plurality of Orthogonal Frequency Division Multiple Access (OFDMA) symbols as a ranging preamble code; and using the ranging preamble code for periodic ranging via a synchronized ranging channel (S-RCH),
wherein the cyclic shift is determined by:

exp
⁡

(

-

j
·
π
·
2
·
k
·

s
p

·

N
TCS

N
FFT

)

,

⁢

k
=
0

,
1
,
…
⁢

,

N
RP

-
1

,

where:
s p is a cyclic shift index,
N TCS is the cyclic shift unit per OFDMA symbol in the time domain,
N FFT is a fast Fourier transform (FFT) size, and
N RP is a length of the ranging preamble code per OFDMA symbol.

2. The method of claim 1 , wherein N TCS =G*N FFT , where G is a cyclic prefix (CP) ratio.

3. The method of claim 1 , wherein the ranging preamble code is determined by:

x
p

⁡

(

n
,
k

)

=

exp
⁡

(

-
j

·

π
⁡

(

r
p

·

(

n
·
71

+
k

)

⁢

(

n
·
71

+
k
+
1

)

211

+

2
·
k
·

s
p

·

N
TCS

N
FFT

)

)

,

⁢

k
=
0

,
1
,
…
⁢

,

N
RP

-
1

;

⁢

n
=
0

,
1
,
2

where:
r p is a root index of the ZC sequence,
s p is a cyclic shift index,
N TCS is the cyclic shift unit per OFDMA symbol in the time domain,
N FFT is the FFT size,
N RP is a length of the ranging preamble code per OFDMA symbol, and
n is an OFDMA symbol index.

4. The method of claim 1 , wherein a length of the ranging preamble code is 72.

5. The method of claim 1 , wherein a number of the plurality of OFDMA symbols is 3.

6. The method of claim 1 , further comprising mapping the ranging preamble code to each of the plurality of OFDMA symbols.

7. The method of claim 1 , wherein a cyclic shift unit by which the cyclic shift is applied is equal to or less than a length of the ranging preamble code.

8. An apparatus for generating a ranging preamble code, the apparatus comprising: a radio frequency (RF) unit configured to at least transmit or receive a radio signal; and a hardware process

Assignees

• Lee Hyun Woo
• Cho Han Gyu
• Kwak Jin Sam
• Kwon Yeong Hyeon
• Lg Electronics Inc

Inventors

• Lee Hyun Woo
• Cho Han Gyu
• Kwak Jin Sam
• Kwon Yeong Hyeon

Classifications

• H04L27/2613 Primary

  Structure of the reference signals · CPC title