Transcript PPT - Electronic Navigation Research Institute

3rd Asia-Oceania Regional Workshop on GNSS
Nov. 1, 2011 @Jeju Island, South Korea
QZSS Observation Data
Available to the Public
Takeyasu SAKAI
Electronic Navigation Research Institute, Japan
Nov. 2011 - Slide 1
Introduction
• QZSS (Quasi-Zenith Satellite System) program:
– Regional navigation service broadcast from high-elevation angle by three or
more satellites on the inclined geosynchronous (quasi-zenith) orbit;
– Broadcast GPS-like supplement signals on three frequencies and two
augmentation signals, L1-SAIF and LEX; ENRI is working for L1-SAIF;
– The first QZS satellite successfully launched on Sept. 11, 2010;
– Technical verification is ongoing by some research organizations.
• Broadcasting ranging signals constantly:
– Ranging signals are broadcast constantly and stable; Now no alert flag;
– QZS-1 is in the operational phase while technical verification is ongoing;
– Now need to promote rapid spread of QZSS capability to consumer equipment.
• ENRI just began continuous observation of QZSS:
– Measures all signals on triple frequencies except LEX;
– We have decided to make observations open to the public for promotion of
R&D on QZSS applications;
– Daily RINEX files are publicly available for free of charge on the web.
Nov. 2011 - Slide 2
QZSS Signals
Signal
Center Freq.
Bandwidth
Min. Rcv Power
L1CD
24 MHz
–163.0 dBW
L1CP
24 MHz
– 158.25 dBW
QZS-L1-C/A
24 MHz
– 158.5 dBW
QZS-L1-SAIF
24 MHz
– 161.0 dBW
24 MHz
– 160.0 dBW
25 MHz
– 157.9 dBW
25 MHz
– 157.9 dBW
42 MHz
– 155.7 dBW
QZS-L1C
1575.42 MHz
Supplement
Signals
(JAXA)
QZS-L2C
1227.6 MHz
L5I
Augmentation
(ENRI)
QZS-L5
L5Q
QZS-LEX
Augmentation
(JAXA/GSI)
1176.45 MHz
1278.75 MHz
• Supplement Signals: L1C/A, L2C, and L5 are GPS-like (PRN193);
• Augmentation Signals: L1-SAIF is SBAS-like (PRN183); LEX is original signal;
• For detail, see IS-QZSS. URL: http://qz-vision.jaxa.jp/USE/is-qzss/index_e.html
Nov. 2011 - Slide 3
Continuous Observation
• Observation conditions:
– ENRI just began continuous observation of L1-SAIF signal for technical
verification in October 2011; Also observes other supplement signals;
– Observation is available on the web: URL http://www.enri.go.jp/sat/qzss_e.htm
– Range measurements are converted into RINEX format and navigation
message is formatted in EMS file; Both are slightly extended for QZSS;
– Data files are stored on daily basis.
Receiver
JAVAD ALPHA-G3T
Antenna
Location
ENRI, Tokyo - Top of the tower of No. 6 Building
35.679518936N 139.560964491E 109.1971m from ellipsoid
X=-3947737.9910 Y=3364428.7640 Z=3699428.9764
Antenna
Trimble Zephyr Geodetic 2 (L1/L2/L5)
Target SV
Measurements
GPS, GLONASS, SBAS, QZSS (incl. L1-SAIF)
Code Range, Carrier Range, Doppler, C/N0 (L1, L2, L5)
Note - Sometimes there is missing data due to some reason such as power outage.
Nov. 2011 - Slide 4
Equipment Setup
JAVAD Rx
ANT
Trimble Zephyr Geodetic 2
Ethernet
Converter
Serial
Realtime Data Collection
LAN
Linux
Server
Nov. 2011 - Slide 5
Observation: RINEX Format
• Extension of existing RINEX format:
– The current RINEX format does not support QZSS; SV identifier is not defined
for QZSS signals;
– Observation is provided in RINEX 2.11 format with an extension;
– For supplement signals we use “Jnn” regarding other core systems;
– For L1-SAIF augmentation signal, we use “Snn” like SBAS.
Status
Fixed
Our
Extension
System
ID
Value of nn
GPS
Gnn
PRN
GLONASS
Rnn
Slot Number
SBAS
Snn
PRN-100
For QZS-1
Galileo
Enn
PRN
Supplement: J01
L1-SAIF：
S83
COMPASS
Cnn
PRN
QZSS
Jnn
PRN-192
L1-SAIF
Snn
PRN-100
Nov. 2011 - Slide 6
Example of RINEX Observation
2.11
OBSERVATION DATA
G (GPS)
RINEX VERSION / TYPE
dat2rnx 1.00
20111019 01:16:43UTCPGM / RUN BY / DATE
dat2rnx 1.00 (Oct 18 2011)
COMMENT
MTKB
MARKER NAME
ENRI, JAPAN
ELECTRONIC NAVIGATION RES INST, JAPAN
OBSERVER / AGENCY
1
TR_G3TH_4
3.4.0a3_qzss8 Jun,10REC # / TYPE / VERS
Large # of
1
TRM55971.00
ANT # / TYPE
measurements
-3947737.9910 3364428.7640 3699428.9764
APPROX POSITION XYZ
0.0000
0.0000
0.0000
ANTENNA: DELTA H/E/N
1
1
WAVELENGTH FACT L1/2
14
L1
C1
P1
D1
S1
L2
C2
P2
D2# / TYPES OF OBSERV
S2
L5
C5
D5
S5
# / TYPES OF OBSERV
2011
10
18
0
0
0.0000000
GPS
TIME OF FIRST OBS
2011
10
18
23
59
59.0000000
GPS
TIME OF LAST OBS
21 SVs
END OF HEADER
11 10 18 0 0 0.0000000 0 21R23R21G07S37G19G13S29G03R12R22G16G30
G31R10R20G06R11G21G23J01S83
QZSS
Epoch Time
131781550.7370
24635168.7740
24635170.4044
2895.0620
38.0000
102496754.6854
24635189.4140
24635186.6924
2251.6814
35.7504
Carrier
C/A code
P/Y :code
Doppler
C/N0
:
133569864.0430
25417497.0210
25417498.3644
2635.4920
38.2500
104080417.5974
25417501.4880
25417504.3784
2053.3764
19.0004
195451243.8520
194779121.9180
151775927.3420
145451928.7700
194779167.9350
37193140.8190
L2C code :
:
37065243.8380 L5 code
37065245.7170
37065250.8380
-539.3800
37065241.0500
GLO
Slot 23
GPS
PRN 07
-995.3470
42.7500
SBAS
PRN 137
-722.2830
-562.8480
48.0000
-722.2760
44.7500
42.5000
QZS-1
L1 C/A
43.7500
QZS-1
L1-SAIF
Nov. 2011 - Slide 7
Navigation Message: EMS File
• Extension of EMS File Format:
– Navigation messages broadcast on L1C/A-equivalent ranging signals are decoded
and archived in the extended EMS Format;
– EMS format is used in EGNOS Data Archive Service (EDAS); Originally contains
only EGNOS broadcast messages;
– Our extension: Including GPS/GLONASS/QZSS navigation messages additionally.
Format
PRN YY MM DD HH MM SS TT data…
PRN
PRN number by which the message is broadcast
YY MM DD
Date
HH MM SS
Time (Transmission of the first bit of the message)
Parameter
TT
data…
GPS/QZSS: Subframe ID (1 to 5)
300 bits = Every 6s
GLONASS: String ID (1 to 15)
100 bits = Every 2s
SBAS/SAIF: Message Type (0 to 63) 250 bits = Every 1s
Message contents (Hexadecimal; The first bit of the
message is stored as MSB of the first char)
Nov. 2011 - Slide 8
Order of completion of message decoding
Example of EMS File
137
129
183
60
58
11
11
11
11
11
10
10
10
10
10
18
18
18
18
18
00
00
00
00
00
00
00
00
00
00
48
137
129
183
137
129
183
60
58
11
11
11
11
11
11
11
11
11
10
10
10
10
10
10
10
10
10
18
18
18
18
18
18
18
18
18
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
48 11 10 18 00 00
7 11 10 18 00 00
19 11 10 18 00 00
21
23
137
129
193
183
137
129
183
PRN
11
11
11
11
11
11
11
11
11
10
10
10
10
10
10
10
10
10
18
18
18
18
18
18
18
18
18
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
Epoch Time
02 25 9A6610581702DFA7FBFF808000...2B00 (64
02 63 9AFC0000000000000000000000...7700 (64
02 50 9ACA06292A06079C2421E79968...4D00 (64
02 9 480BC1BA68F4C024B5D6992CE0
02 9 480BC1BA68F4C024B5D6992CF0
:
02 9 480BC1BA68F4C024B5D6992C00
03 2 C608DFFC009FFDFFC003FFDFFD...3500 (64
03 2 C609DFFC011FFDFFC013FD5FFD...D000 (64
03 51 C6CE03B79FB824827D84B7D020...1AC0 (64
04 3 530CDFFC005FFDFFC00DFFFFF7...7D00 (64
04 3 530EDFFC011FFDFFC011FFC000...7300 (64
04 51 53CE8477D878477BFF85D007F8...8180 (64
04 10 55B8AC6957F0A00C0F7D592CE0
04 10 55B8AC6957F0A00C0F7D592CF0
:
04 10 55B8AC6957F0A00C0F7D592C00
00 1 8B09E8E8E1029C09E90002DEA1...8D00 (76
00 1 8B09E8E8E1029C09E90002DEA1...F800 (76
:
00 1 8B09E8E8E1029C09E90002DEA1...3CC0 (76
00 1 8B09E8E8E1029C09E90002DEA1...4A00 (76
05 4 9A11DFFDFFFFF7FF1FFFFEBFDD...9C00 (64
05 4 9A12DFFDFFC007FFDFFFFE3FD1...3B00 (64
00 1 8B000048E10217C9EA00426000...8800 (76
05 2 9A081FFDFFC001FFDFFFFF9FFD...B500 (64
06 28 C67308C963CF4080702A827907...FE00 (64
06 28 C67308CB63EF7080702D027917...BD00 (64
06 3 C60C1FFDFFC001FFDFFC005FFC...1180 (64
Msg ID
Data
chars)
chars)
chars)
SBAS/L1-SAIF
GLONASS
chars)
chars)
chars)
chars)
chars)
chars)
SBAS/L1-SAIF
GLONASS
chars)
chars)
chars)
chars)
chars)
chars)
chars)
chars)
chars)
chars)
chars)
GPS
SBAS/L1-SAIF
QZSS L1C/A
SBAS/L1-SAIF
Nov. 2011 - Slide 9
Discussion
• Is RINEX appropriate for data publication?
– So far, RINEX seems most commonly used data exchange format;
– Option: BINEX and RTCM 3.0 could be used (also for realtime?).
• Some applications are not capable of large # of measurements:
– Need degraded version of observation, for example, 2-frequency version?
• Is RINEX navigation message file necessary? (Is EMS file enough?)
– RINEX navigation file (*.YYn) is easily applicable to QZSS L1-C/A;
– L1-SAIF message: Ephemeris message may be stored in RINEX file (*.YYh); But
other messages have little option other than EMS (or similar) format;
– An idea: Store L1-SAIF messages in RINEX observation file using comment record.
• Does anyone need realtime distribution?
– ENRI is ready for realtime distribution;
 Data collection is performed in a realtime manner;
 Communication line available for realtime distribution may be less capacity.
– ENRI is also collecting data at some locations inside Japan.
Nov. 2011 - Slide 10
Conclusion
• QZSS needs promotion:
– QZS-1 is in the operational phase while technical verification is ongoing;
– Need promotion for rapid spread of QZSS capability to consumer equipment.
• ENRI’s contribution:
– Began continuous observation of QZSS and data publication;
– Measures all signals on triple frequencies except LEX;
– Daily RINEX files are publicly available for free of charge on the web.
URL http://www.enri.go.jp/sat/qzss_e.htm
• Proposal:
– SV identifier for RINEX observation:
 For supplement signals, use “Jnn” (J01 for QZS-1) regarding other core
systems;
 For L1-SAIF augmentation signal, use “Snn” (S83 for QZS-1) like SBAS.
• Feedback your comments to: [email protected]