3GPPFDD_EVM_NonSyn
Description: 3GPP FDD EVM measurement
Library: 3GPPFDD, Measurement
Class: SDF3GPPFDD_EVM_NonSyn
Derived From: 3GPPFDD_MeasBase
Parameters
Name |
Description |
Default |
Unit |
Type |
Range |
---|---|---|---|---|---|
SpecVersion |
version of specifications: Version_03_00, Version_12_00, Version_03_02 |
Version_12_00 |
|
enum |
|
LinkDir |
link direction: Downlink, Uplink |
Uplink |
|
enum |
|
SlotFormat |
slot format |
0 |
|
int |
† |
ScrambleCode |
index of scramble code |
0 |
|
int |
[0:512] for downlink; |
Scramble |
scramble code type: LONG, SHORT |
LONG |
|
enum |
|
ScrambleOffset |
scramble code offset |
0 |
|
int |
[0:15] |
ScrambleType |
scramble code type: normal, right, left |
normal |
|
enum |
|
SpreadCode |
index of spread code |
0 |
|
int |
[0:SF-1]; |
SampleRate |
sample rate |
8 |
|
int |
[1:256] |
StartSlot |
number of slot to be ignored |
0 |
|
int |
[0, ∞) |
SlotNum |
slot number |
1 |
|
int |
[1:15] |
Correlator |
correlator method: Coherent, NonCoherent |
Coherent |
|
enum |
|
SCH |
switch for SCH: SCH_On, SCH_Off |
SCH_On |
|
enum |
|
CPICH |
switch for CPICH: CPICH_On, CPICH_Off |
CPICH_Off |
|
enum |
|
EVMValue |
EVM value expression options: EVM_Ratio, EVM_Percent |
EVM_Percent |
|
enum |
|
Correct_IQ_Offset |
switch for IQ offset correction: Yes, No |
Yes |
|
enum |
|
DUT_DelayBound |
DUT delay bound |
.00001 sec |
sec |
real |
[0:(400.0/3840000)] |
† [0:5] for uplink DPCCH;
[0:16] for downlink DPCH;
[0:17] for downlink SCCPCH;
[0:5] for uplink PCPCH (Ver 03_00);
[0:2] for uplink PCPCH (Ver 12_00);
[0:1] for uplink PCPCH (Ver 03_02);
Uplink DPCCH spread factor is 256;
Spread Factor is 512 when down link DPCH SlotFormat is 0 and 1;
Spread Factor is 256 when down link DPCH SlotFormat is 2, 3, 4, 5, 6, and 7;
Spread Factor is 128 when down link DPCH SlotFormat is 8, 9, 10, and 11;
Spread Factor is 64 when down link DPCH SlotFormat is 12;
Spread Factor is 32 when down link DPCH SlotFormat is 13;
Spread Factor is 16 when down link DPCH SlotFormat is 14;
Spread Factor is 8 when down link DPCH SlotFormat is 15;
Spread Factor is 4 when down link DPCH SlotFormat is 16;
Pin Inputs
Pin |
Name |
Description |
Signal Type |
---|---|---|---|
1 |
test |
tested signals |
complex |
2 |
ref |
reference signals |
complex |
Notes/Equations
- This subnetwork model measures EVM that is used to evaluate modulation accuracy. The schematic for this subnetwork is shown in the following figure.
3GPPFDD_EVM_NonSyn Schematic
In the 2003C release, 3GPPFDD_EVM_NonSyn provides a new method for EVM measurement compared to 3GPPFDD_EVM.
To measure EVM, the reference signal and test signal must be fully time-aligned. 3GPPFDD_EVM reference and test signals are synchronized using the spreading code. Because the EVM value relies on the synchronization performance, if the test signal is severely impaired the EVM calculation may be erroneous.
3GPPFDD_EVM_NonSyn uses the spreading code to synchronize the reference signals only. The noise-free reference signal can be accurately aligned at the slot boundary.
The EVM is calculated by probing the minimum differences between the reference signals (aligned at slot boundary) and test signals (not aligned at slot boundary) over a window size that is determined by DUT_DelayBound. The EVM is the minimum when the test and reference signals are fully aligned.
This method is very robust against impairments imposed on test signals. The simulation time is linearly proportional to the EVM probing window size (determined by DUT_DelayBound). The simulation time is approximately 30 seconds for a window size of 128, in a P4/1.7G 512M PC (powered by ADS 2003C and MS Windows 2000). - The 3GPP system chip rate is 3.84 Mcps. The BS_Tx_EVM.dsn design demonstrates the use of this model in File > Example Project > WCDMA3G > WCDMA3G_BS_Tx_prj; this project is discussed in Base Station Transmitter Design Examples.
References
- 3GPP Technical Specification TS 34.121 V3.8.0, Terminal Conformance Specification, Radio Transmission and Reception (FDD), March 2003, Release 1999.
http://www.3gpp.org/ftp/Specs/2002-03/R1999/34_series/34121-380.zip