Site Information for Singapore

NTUS (Nanyang Technological University)

Marker ID: 22601M001
Operator: Leica Geosystems Singapore
Log file: ntus00sgp_20240216.log

Receiver

Installed	week/d doy	Removed	week/d doy	Receiver type	S/N	Firmware
1997-06-26T03:00Z	0911/4 177	1999-09-02T00:00Z	1025/4 245	ROGUE SNR-8000	175	3.2.32.1
1999-10-28T06:00Z	1033/4 301	2000-10-20T00:00Z	1084/5 294	AOA SNR-12 ACT	229	3.3.32.3
2001-02-22T05:20Z	1102/4 053	2001-03-11T00:00Z	1105/0 070	AOA SNR-12 ACT	224	3.3.32.3
2001-06-18T03:40Z	1119/1 169	2006-11-03T00:00Z	1399/5 307	AOA SNR-12 ACT	225	3.3.32.4
2007-06-01T00:00Z	1429/5 152	2007-09-20T10:40Z	1445/4 263	LEICA GRX1200GGPRO	352729	5.10/3.013
2007-09-20T10:58Z	1445/4 263	2007-11-21T02:50Z	1454/3 325	LEICA GRX1200GGPRO	352729	5.50/
2007-11-21T02:50Z	1454/3 325	2008-03-07T07:00Z	1469/5 067	LEICA GRX1200GGPRO	352729	5.60/3.014
2008-03-07T07:00Z	1469/5 067	2009-09-03T07:24Z	1547/4 246	LEICA GRX1200GGPRO	352729	5.62/3.014
2009-09-03T07:45Z	1547/4 246	2010-04-05T08:30Z	1578/1 095	LEICA GRX1200GGPRO	352729	7.53/3.015
2010-04-05T08:30Z	1578/1 095	2010-05-10T06:53Z	1583/1 130	LEICA GRX1200GGPRO	352729	7.80/3.018
2010-05-10T07:04Z	1583/1 130	2011-01-25T03:14Z	1620/2 025	LEICA GRX1200GGPRO	352729	7.80/3.019
2011-01-25T06:28Z	1620/2 025	2014-07-27T03:00Z	1803/0 208	LEICA GRX1200GGPRO	352729	8.10/3.019
2014-12-20T09:06Z	1823/6 354	2017-04-24T07:50Z	1946/1 114	LEICA GRX1200GGPRO	352729	8.10/3.055
2017-04-24T08:00Z	1946/1 114	2018-04-18T02:40Z	1997/3 108	LEICA GRX1200GGPRO	352729	9.20/3.823
2018-04-18T02:50Z	1997/3 108	2021-11-25T10:40Z	2185/4 329	LEICA GR50	1832415	4.20/7.300
2021-11-25T10:40Z	2185/4 329	2022-02-14T01:24Z	2197/1 045	LEICA GR50	1832415	4.51/7.710
2022-02-14T01:24Z	2197/1 045	2022-08-03T05:19Z	2221/3 215	LEICA GR50	1832415	4.52/7.711
2022-08-03T05:19Z	2221/3 215	2022-11-23T02:06Z	2237/3 327	LEICA GR50	1832415	4.60/7.811
2022-11-23T02:06Z	2237/3 327	2023-08-15T18:23Z	2275/2 227	LEICA GR50	1832415	4.61/7.811
2023-08-15T18:23Z	2275/2 227	2024-02-14T18:14Z	2301/3 045	LEICA GR50	1832415	4.70/7.813
2024-02-14T18:14Z	2301/3 045			LEICA GR50	1832415	4.80/7.900

Antenna

Installed	week/d doy	Removed	week/d doy	Antenna type	Dome	S/N	Height	Antenna calibration
1997-06-26T03:00Z	0911/4 177	1998-05-07T08:00Z	0956/4 127	AOAD/M_T	NONE	177	0.0776	AOAD-M_T_RFI____NONE_177.atx
1998-06-08T00:00Z	0961/1 159	2007-05-16T00:00Z	1427/3 136	AOAD/M_T	NONE	222	0.0776	AOAD-M_T_RFI____NONE_222.atx
2007-05-16T00:00Z	1427/3 136	2018-04-18T02:40Z	1997/3 108	LEIAT504GG	NONE	200240	0.0776
2018-04-18T02:50Z	1997/3 108			LEIAR20	LEIM	20288014	0.0776

External Frequency

Installed	week/d doy	Removed	week/d doy	Ext. Frequency type
1997-06-26T03:00Z	0911/4 177			INTERNAL

Notes

1997-06-26T03:00Z 0911/4 177 - 2010-10-05T00:00Z 1604/2 278

NTUS is operated jointly for IGS by Singapore Land Authority (SLA) and the Delft University of Technology (DUT/DEOS).

1997-06-26T03:00Z 0911/4 177 - 2006-11-03T00:00Z 1399/5 307

No rawdata files are available for the following periods (week/dow): until 999/6; 1011/2-1068/5; 1083/2; 1226/2-1232/3; 1310/4-1318/1; 1320/0-1321/1;1322/1-1323/0;1327/6-1329/2;1371/4; 1372/2 and 1372/3. Also, there are gaps in the rinex data for this period.

1997-06-26T03:00Z 0911/4 177 - 2007-05-16T00:00Z 1427/3 136

The antenna is mounted on a pillar with a SOKIA Tribrach. The pillar (approx. 1.50m high) is located on the building of the Survey Laboratory of the School of Civil and Structural Engineering of the Nanyang Technological University at Singapore

2006-11-03T00:00Z 1399/5 307 - 2007-05-16T00:00Z 1427/3 136

At the time the AOA_DM/T antenna was dismantled, the antenna was warbling as the tribrach and adaptor was not secure due to wear and tear. The antenna was also orientated to the East instead of North based on the position of the cable connector. It is not known since when this condition existed, but we suspect it happened at the end of life of the AOA Turbo Rogue receiver (after this receiver stopped functioning). However, it may have affected the time series at the end of 2006.

2007-05-16T00:00Z 1427/3 136 -

The antenna is mounted on a pillar with a LEICA GDF 111-1 Tribrach and rotatable Tribrach adapter (replacing the damaged SOKIA Tribrach and adapter). The new antenna was installed at a height within a accuracy of 0.5mm compared to the previously installed antenna. It was also orientated to the North within +/-2deg. The pillar (approx. 1.50m high) is located on the building of the Survey Laboratory of the School of Civil and Structural Engineering of the Nanyang Technological University at Singapore. There is another choke ring antenna with radome, one of the 5 national permanent reference stations, about 2m away. There is a lightning arrestor on the same roof about 4m away. Before the installation of the LEICA antenna, the pillar, received some minor rust-proofing cum painting work and heat shielding (with a pvc pipe with holes).

2010-10-05T00:00Z 1604/2 278 -

Singapore Land Authority (SLA) has taken over the operation of the station from Nanyang Technological University (NTU)

2014-07-27T03:00Z 1803/0 208 - 2014-12-20T09:06Z 1823/6 354

Receiver did not track satellites during this period due to firmware problem. Firmware was upgraded on 20 Dec 2014 and receiver started tracking again.

2015-04-05T04:00Z 1839/0 095 - 2016-04-04T13:33Z 1891/1 095

The LDC is not receiving any data due to unresolved and unknown issues.

2016-04-04T13:33Z 1891/1 095 - 2016-05-17T08:00Z 1897/2 138

The receiver is on-line again after installing a cellular modem and internet configuration. There is however an issue with the data, at regular intervals the receiver is not tracking any satellites.

2016-05-17T08:00Z 1897/2 138 - 2017-03-08T09:00Z 1939/3 067

The LDC is not receiving any data due to unresolved and unknown issues.

2017-03-08T09:00Z 1939/3 067 - 2017-04-19T19:00Z 1945/3 109

Connection to receiver has been restored and receiver is sending data again after a new antenna cable was installed. However, there during periods of the day the receiver is not tracking any data. After some time GLONASS was disabled to due some further checking, but this did not resolve the problem. On 19 April 2017 an attempt was made to upgrade the f/w to version 9.20/3.823, but failed, leaving the receiver in an inoperative state. On April 24 2017 the receiver was physically reset and f/w upgrade to version 9.20/3.823 was made. The data that was received during this period is available at the LDC, but has not been uploaded to IGS.

2017-03-08T09:00Z 1939/3 067 -

Uploads to IGS have been restarted after the upgrade to f/w version 9.20/3.823.