PSS信号主要用于信号的同步。它的特点如下:
- Mapped to 127 active sub carriers around the lower end of the system bandwidth (subcarrier 80~206)
- Made up of 127 m-Sequence Values
- Used for Downlink Frame Synchronization
- One of the critical factors determining Physical Cell ID
LTE PSS 和 NR PSS
NR PSS采用的是m序列，LTE PSS采用的是Zadoff-chu序列。
<38.211 - 7.4.2.1.1>NR:
d(n)=1−2x(m)
d
(
n
)
=
1
−
2
x
(
m
)
<36.211 - 6.11.1.1>LTE:
du(n)=e−jπun(n+1)63,n=0,1,2,...,30
d
u
(
n
)
=
e
−
j
π
u
n
(
n
+
1
)
63
,
n
=
0
,
1
,
2
,
.
.
.
,
30
du(n)=e−jπu(n+2)(n+1)63,n=31,32,...,61
d
u
(
n
)
=
e
−
j
π
u
(
n
+
2
)
(
n
+
1
)
63
,
n
=
31
,
32
,
.
.
.
,
61
Ref
[1] 38.211 NR;Physical channels and modulation(Release 15)
m sequence
Zadoff-Chu Sequence
零自相关序列。
为同步而生的啊， LTE系统中用它作为前导序列。
