General Description
R&S
®
CMW-KN5xx
15
User Manual 1176.7690.02 ─ 05
Channel Bandwidth [MHz]
1.4
3
5
10
15
20
Resource Blocks (RB)
6
15
25
50
75
100
In the time domain the additional units radio frame, subframe and slot (containing the
OFDM symbols) are defined. A guard time called Cyclic Prefix (CP) is added to each
OFDM symbol. Depending on the duration of the guard time, it is either called normal
CP or extended CP and the slot contains either 7 or 6 OFDM symbols. For the "LTE
eNodeB Multi Evaluation" measurement only signals with normal CP are relevant. So
each slot contains 7 OFDM symbols.
The basic time unit in LTE is the sample interval T
s
. T
s
can be calculated from the sam-
pling frequency 30.72 MHz: 1 T
s
= 1/30.72 MHz
≈
32.55 ns.
Fig. 3-5: LTE DL slot structure, normal CP
The radio frame structure depends on the duplex mode. An FDD DL radio frame con-
tains 20 DL slots, grouped into 10 subframes.
Fig. 3-6: LTE DL frame structure for FDD
A TDD radio frame is also divided into 10 subframes. But for TDD three subframe
types are defined: DL subframe (2 DL slots), UL subframe (2 UL slots) and special
subframe. A special subframe contains the fields DwPTS, GP and UpPTS. 3GPP
defines several possible special subframe configurations, resulting in different lengths
of these fields, see 3GPP TS 36.211, table 4.2-1. The total length of a special sub-
frame equals 1 ms (same length for all subframe types).
LTE DL Signal Properties
深圳德标仪器
135-1095-0799
