Post on 25-Aug-2020
transcript
Operating OpenAirInterface in mmWave band
Ren-Jr Chen
rjchen@itri.org.tw M300/ICL/ITRI 2019/12/4
Copyright 2019 ITRI 工業技術研究院
Agenda
Overview of OAI operating in mmwave band (28GHz)
Mmwave phase array module EVM test
Beamforming test
Stability test
OAI code test Test LDPC decoding performance
Test OAI code through phase array module
2
Copyright 2019 ITRI 工業技術研究院
Overview of OAI operating in mmwave band (28GHz)
3
Copyright 2019 ITRI 工業技術研究院
Components
OAI code version:
OAI git-version: branch: develop-nr, commit-id=26f1e090 08/23/2019
Baudrate: 61.44MHz, SISO I/Q, FFT SIZE:2048, CS:30kHz
Ethernet throughput: 61.44MHz x 32 bits ~= 1.966 Gbps
Computer model: (DIY computer)
CPU: Intel i7-9700K 3.6GHz
DDR: DDR4 32GB
OS: Ubuntu 16.04 (real-time kernel 4.4.15-rt23)
Mmwave phase array module
ITRI software define radio
4
Copyright 2019 ITRI 工業技術研究院
Mmwave Phase array front-end module
5
Copyright 2019 ITRI 工業技術研究院
Summary of mmwave module
Two streams, each stream for different polarization, including IF to RF upconverter, PA, LNA, phase shift, VGA, TX/RX switch …
9.6cm
15
cm
PA
PA
PA
PA
LO
IF
IF
5bits 5bits16 PAs
LNA
LNA
LNA
LNA
LO
IF
IF
5bits 5bits
16 LNA
16 PAs
16 LNA
2.5GHz~4GHz
2.5GHz~4GHz
RF:~28GHz, 800MHz BW
Copyright 2019 ITRI 工業技術研究院
Polarization
7
Vertical direction feeding point
Horizontal direction feeding point
Copyright 2019 ITRI 工業技術研究院
How many stream is better?
Which one is better?
8
PA
PA
DAC
PA
PA
ADC
PA
PA
DAC
PA
PA
ADC
H-pol
V-pol
PA
PA
DAC
PA
PA
DAC
PA
PA
DAC
PA
PA
DAC
PA
PA
ADC
PA
PA
ADC
H-pol
V-pol
PA
PA
DAC
PA
PA
DAC
PA
PA
DAC
PA
PA
DAC
PA
PA
ADC
PA
PA
ADC
H-pol
V-pol
PA
PA
ADC
PA
PA
ADC
Copyright 2019 ITRI 工業技術研究院
Rank Issue in beamforming
rank?
BF ℎ11 ℎ21ℎ12 ℎ22
… ℎ𝑛1… ℎ𝑛2
⋮ ⋮ℎ1𝑚 ℎ2𝑚
⋱ ⋮… ℎ𝑚𝑛
9
PA
PA
DAC
PA
PA
ADC
PA
PA
DAC
PA
PA
ADC
: Dual polarization (7m) : Same polarization (7m)
Copyright 2019 ITRI 工業技術研究院
Polarization in beamforming
Polarization could help the rank condition in two layers beamforming
10
PA
PA
DAC
PA
PA
DAC
PA
PA
DAC
PA
PA
DAC
Fixed antenna element Fixed array antenna gain
Copyright 2019 ITRI 工業技術研究院
Rank Issue in beamforming
11
Copyright 2019 ITRI 工業技術研究院
EVM Test
Overall EVM from TX to RX
12
BS
UE
Energy Surface
SC/CASE/EVM
SDR+RF
15K -30.9
30K -31.2
60K -31.4
120K -31.4
240K -31.4
Copyright 2019 ITRI 工業技術研究院
Fast beamforming capability
How fast we need?
Subfram 0
Slot 0
0.586 ms8.333 ms
9.440 ms
Subfram 1 Subfram 2 Subfram 91 frame = 10 subframes
1 subframe = 8 slots
1 slot = 14 OFDM symbols
1 radio frame = 10 ms
1.0 ms
125.391 ms
1.107 ms8.333 ms
8.919 ms
Slot 1
124.870 ms
Symbol 13CP
1
Symbol 2CP
1Symbol 1C
P1
0.586 ms8.333 ms
8.919 ms
1 slot = 14 OFDM symbols
0.586 ms8.333 ms
8.919 ms
Symbol 13CP
1
Symbol 2CP
1
Symbol 1CP
1
Symbol 0CP
0
Symbol 1CP
1
72 1024 72 1024 72 1024 72 1024
72 102472 102472 1024136 1024
15408 15344
122880 122880 122880 122880
Slot 2 Slot 3 Slot 4 Slot 5 Slot 6 Slot 7
1540815344 15344 15344 15344 15344
125.391 ms 124.870 ms
13
Copyright 2019 ITRI 工業技術研究院
Fast beamforming issue
TDL-A channel, Frequency band : 28GHz, CS=120kHz
14
Copyright 2019 ITRI 工業技術研究院
How to Control mmwave module?
Preload your wanted beam pattern into mmwave module
Select beam pattern when TX and RX
15
Copyright 2019 ITRI 工業技術研究院
Define and Preload Beam Pattern
16
PA
PA
PA
PA
LO
IF
IF
5bits 5bits16 PAs
16 PAs
8 beam table
8 beam table
Transmit
Beamforming
H-pol
V-pol
LNA
LNA
LNA
LNA
LO
IF
IF
5bits 5bits
16 LNA
16 LNA
8 beam table
8 beam tableH-pol
V-pol
Received
Beamforming
H_TX_Phase{1,3} = [0 45 90 135; 0 45 90 135; 0 45 90 135; 0 45 90 135]
H_TX_Att{1,3} = [10 10 10 10; 10 10 10 10; 10 10 10 10; 10 10 10 10]
H_TX_Att=cell(1,8);
H_TX_Phase=cell(1,8);
H_RX_Att=cell(1,8);
H_RX_Phase=cell(1,8);
V_TX_Att=cell(1,8);
V_TX_Phase=cell(1,8);
V_RX_Att=cell(1,8);
V_RX_Phase=cell(1,8);
Reference point
Copyright 2019 ITRI 工業技術研究院
SS Block
17
Subframe #0 Subframe #1 Subframe #2 Subframe #3 Subframe #4 Subframe #5 Subframe #6 Subframe #7 Subframe #8 Subframe #9
#0Beam #1
Slot #0 Slot #1 Slot #2 Slot #3 Slot #4 Slot #5 Slot #6 Slot #7
#2 #3 #4 #5 #6 #7
4 8 16 20 32 36 44 48 60 64 72 76 88 92 100 104
#8 #9 #10 #11 #12 #13 #14 #15
Subframe #0
Slot #0 Slot #1 Slot #2 Slot #3 Slot #4 Slot #5 Slot #6 Slot #7
Subframe #1
Slot #0 Slot #1 Slot #2 Slot #3 Slot #4 Slot #5 Slot #6 Slot #7
Subframe #2
144 148 156 160 172 176 184 188 200 204 212 216 228 232 240 244
Slot #0 Slot #1 Slot #2 Slot #3 Slot #4 Slot #5 Slot #6 Slot #7
Subframe #3
Slot #0 Slot #1 Slot #2 Slot #3 Slot #4 Slot #5 Slot #6 Slot #7
Subframe #4
284 288 296 300 312 316 324 328 340 344 352 356 268 372 380 384 424 428 436 440 452 456 464 468 480 484 492 496 508 512 520 524
PSS SSS PBCH
#0Beam #1
Slot #0 Slot #1 Slot #2 Slot #3 Slot #4 Slot #5 Slot #6 Slot #7
#2 #3 #4 #5 #6 #7
4 8 16 20 32 36 44 48 60 64 72 76 88 92 100 104
#8 #9 #10 #11 #12 #13 #14 #15
Subframe #0
Copyright 2019 ITRI 工業技術研究院
For Example
18
Copyright 2019 ITRI 工業技術研究院
Beam Tracking Test
19
B1 B2 B3 B4 B1 B2 B3 B4 B1 B2 B3 B4 B1 B2 B3 B4
B1 B2 B3 B4
BS:
UE:
Copyright 2019 ITRI 工業技術研究院
Test mmwave stability
20
Transmission without any error packet last one week
One packet: 1500 bytes (one maximum IP)
Throughput: ~ 100 Mbps
Copyright 2019 ITRI 工業技術研究院
Test OAI code structure
21
while (1)
RX();
Process_RXdata();
Prepare_TXdata();
TX();
end
while (1)
RX();
Process_RXdata();
Prepare_TXdata();
TX();
end
BS UE
Copyright 2019 ITRI 工業技術研究院
Modify Interface Between PC and FPGA
PC -> FPGA (TX)
22
⋮
Copyright 2019 ITRI 工業技術研究院
Modify Interface Between PC and FPGA
FPGA -> PC (RX)
23
⋮
Copyright 2019 ITRI 工業技術研究院
LDPC decoding test
24
Copyright 2019 ITRI 工業技術研究院
LDPC decoding test
OAI gNB/UE configuration:
Support Downlink : PBCH +DLSCH
SCS=30KHz (one slot=0.5ms), Sampling-Rate: 61.44 MHz ,fft=2048 , Total-PRB=106 (BW=40M),
DLSCH PRB=50PRB .
OFDM Symbol of DLSCH=9 (one slot consists of 14 OFDM symbols , 9 OFDM symbols for DL-Data)
NO parallel LDPC decode in UE
We try to enable “parallel LDPC decode” ,but we encounter error in MA-CPDU when we enable “parallel LDPC decode”. So all the test of LDPC we use is sequential decode.
25
Copyright 2019 ITRI 工業技術研究院
LDPC decoding test
LDPC Decoding Time for PRB=50
26
Copyright 2019 ITRI 工業技術研究院
LDPC decoding test
27
Copyright 2019 ITRI 工業技術研究院
Modify OAI structure for Test OAI code
28
while (1)
Prepare_TXdata();
TX();
Process_RXdata();
RX(); % listen
end
while (1)
RX(); %listen
Process_RXdata();
Prepare_TXdata();
TX();
end
BS UE
Copyright 2019 ITRI 工業技術研究院
OAI MCS-9 + RF-Cable without CFO Compensation
29
Copyright 2019 ITRI 工業技術研究院
OAI MCS-15 + 28G mmWave 4x2 RF with CFO = 2320
30
Copyright 2019 ITRI 工業技術研究院
DEMO in this workshop
5GNR OAI code
31
Beam tracking and real-time DEMO
Copyright 2019 ITRI 工業技術研究院
32