GNSS - Global Navigation Satellite System

GNSS Concept

Space Segment

All Global Navigation Satellite Systems (GNSS) utilize a number of satellites orbiting the Earth along pre-defined paths. Each of these Space Vehicles (SV) transmits specific information needed by GPS receivers (GPSr) to calculate their position:

Almanac - Includes coarse orbit and status information for all satellites in the constellation.
Ephemeris - Contains precise orbital information for the transmitting satellite only.
Identification - Each satellite transmits a unique PRN code to differentiate their signals.
Timestamp - Provides the date and time from an on-board atomic clock.

Control Segment

Also commonly referred to as the Ground Segment or Operational Control Segment, this global network of terrestrial based facilities track, monitor, analyze and transmit commands and data to the satellites in orbit to maintain proper GNSS system operation.

The Master Control Station is the central control node for the GNSS constellation, and is responsible for all aspects of constellation command and control.
Monitoring Stations distributed around the world are equipped with atomic clocks and GNSS receivers tasked with continously collecting local atmoshperic data and satellite navigation signals that are then sent to the Master Control Station for processing.
Ground Antennas located at some Monitoring Station locations are used to transmit commands and processed navigation data received from the Master Control Station to the satellites in orbit.

User Segment

When powered on, the GPSr starts listening for signals from a satellite list created using position and time data stored in the Almanac. If the expected signals are not located, the GPSr will begin cycling from one satellite to the next until a signal is found. A fresh Almanac can then be downloaded in about 13 minutes time.
After the expected signals are aquired, the GPSr will begin loading ephemeris data from each individual satellite. This operation normally requires less than a minute to complete.
The distance to individual satellites can now be determined by comparing the time each signal was transmitted with the time it was received (Signal Travel Time x Speed of Light = Distance to Satellite).
Once the GPSr has the distances and locations to four satellites, an absolute position calculation can be performed using trilateration.
To achieve a desireable level of accuracy, the GPSr clock would have to match the accuracy of the atomic clocks used in each satellite. Since this is not currently possible, the GPSr simply borrows the clock signal from one additional satellite for timing and synchronization purposes. This is why a minimum of four satellite signals are required to calculate an estimated position, and five are necessary for an absolute position.

Satellite Constellations

Your Global Positioning System receiver (GPSr) must utilize information transmitted from one or more satellite constellations (which is best?) to accurately and precisely calculate your current position. Which systems are used and the number of satellite signals available will directly impact device performance and accuracy. See this Garmin GPS Guide for beginners to learn more about how these systems work.

GPS

The Global Positioning System is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. The original concept for a Defense Navigation Satellite System (DNSS) in September 1973 was later named Navstar (NAVigation System using Timing And Ranging), then Navstar-GPS to identify the constellation of Navstar satellites, and eventually shortened simply to GPS. Achieving initial operational capability (IOC) in December 1993, Full Operational Capability (FOC) was declared by Air Force Space Command (AFSPC) in April 1995. The highest quality signals were reserved for military use, and the signal available for civilian use was intentionally degraded. Selective Availability was discontinued on May 2, 2000, allowing users to receive a non-degraded signal globally. GPS is maintained by the United States government and is freely accessible to anyone with a GPS receiver.

• View available GPS satellites.
• Visit GPSrChive GPS discussion forum.

GLONASS

The GLObal NAvigation Satellite System is a space-based satellite navigation system operated by the Russian Aerospace Defence Forces. It both complements and provides an alternative to the United States' Global Positioning System (GPS) and is the only alternative navigational system in operation with global coverage and comparable precision. GLONASS initially achieved Full Operational Capability (FOC) in December, 1995. Financial difficulties crippled the Russian space program, leaving them with only 6 operational satellites by 2001. In 2010, GLONASS had achieved 100% coverage of Russia's territory, and by October 2011, the full orbital constellation of 24 satellites was restored, enabling full global coverage.

• View available GLONASS satellites.
• Visit GPSrChive GLONASS discussion forum.

Galileo

Galileo is the global navigation satellite system (GNSS) that is being created by the European Union (EU) through the European GNSS Agency (GSA), headquartered in Prague in the Czech Republic, with two ground operations centres, Oberpfaffenhofen near Munich in Germany and Fucino in Italy. The project is named after the Italian astronomer Galileo Galilei. Galileo is intended to provide an independent high-precision positioning system so European nations do not have to rely on the Russian GLONASS, Chinese BeiDou or US GPS systems. The first Galileo test satellite, the GIOVE-A, was launched 28 December 2005, while the first satellite to be part of the operational system was launched on 21 October 2011. As of July 2018, 26 of the planned 30 active satellites were in orbit. Galileo started offering Early Operational Capability (EOC) on 15 December 2016, providing initial services with a weak signal, and is expected to reach Full Operational Capability (FOC) in 2019.

• View available Galileo satellites.
• Visit GPSrChive Galileo discussion forum.

BeiDou

The original Chinese BeiDou navigation satellite system (BDS) BeiDou-1 consisted of three satellites and offered limited coverage and services from 2000 through 2012. The second generation BeiDou-2 (COMPASS) system became operational to China in December 2011 with a partial constellation of 10 satellites, and has been providing services to the Asia-Pacific region since December 2012. China's third generation BeiDou-3 system began providing global services on December 27, 2018. The final BDS-3 satellite was launched into orbit on June 23, 2020, completing the newest alternative to GPS, GLONASS and Galileo.

• View available BeiDou satellites.
• Visit GPSrChive BeiDou discussion forum.

NavIC

NavIC (Navigation with Indian Constellation) is the operational name for the Indian Regional Navigation Satellite System (IRNSS), with a space segment consisting of eight satellites. Three satellites are positioned in Geostationary orbit (GEO), while another five satellites operate in an Inclined Geosynchronous orbit (IGSO). Future expansion plans include the development and deployment of five additional satellites in the short term, with long term aspirations of a Global Indian Navigation System (GINS) constellation consisting of 24 satellites.

• View available NavIC satellites.
• Visit GPSrChive NavIC discussion forum.

Iridium

Iridium is the only mobile voice and data satellite communications network that spans the entire globe. It is comprised of six polar orbiting planes, each containing 11 crosslinked satellites totaling 66 in the operational constellation, creating a web of coverage around the Earth. Iridium enables connections between people, organizations and assets to and from anywhere, in real time.

• Visit GPSrChive Iridium discussion forum.

GBAS

The Ground Based Augmentation System (also referred to as Local Area Augmentation System in U.S.) is intended primarily to support precision aviation approach operations. GBAS information is transmitted using VHF signals most handheld Garmin GPS receivers are not equipped to receive.

SBAS

A Satellite Based Augmentation System supports wide-area or regional augmentation through the use of additional satellite-broadcast messages.

• View available SBAS satellites.

WAAS

The Wide Area Augmentation System is a satellite based augmentation system (SBAS) jointly developed by the United States Department of Transportation (DOT) and the Federal Aviation Administration (FAA).

WAAS was commissioned for use on July 10, 2003.

Visit GPSrChive WAAS discussion forum.

EGNOS

The European Geostationary Navigation Overlay Service is a satellite based augmentation system (SBAS) developed by the European Space Agency, the European Commission, and EUROCONTROL.
EGNOS satellites transmit differential correction data to improve the accuracy of positions derived from US GPS satellite signals while providing users with GPS signal reliability information.
EGNOS operations were initiated in July 2005.
An EGNOS Data Access Service was made available in July 2012.
Visit GPSrChive EGNOS discussion forum.

MSAS

The Multi-functional Satellite Augmentation System is a Japanese satellite based augmentation system (SBAS) commissioned on September 27, 2007.
MSAS uses a Dual PRN Multi-functional Transport Satellite (MTSAT) and a network of ground stations to augment GPS signals over Japan.
Visit GPSrChive MSAS discussion forum.

GAGAN

The GPS Aided Geo Augmented Navigation is a regional satellite based augmentation system (SBAS) implemented by the government of India.
GAGAN consists of 3 geostationary satellites, 15 reference stations, 3 uplink stations and 2 control centers.
GAGAN is compatible with other SBAS systems (WAAS, EGNOS, MSAS).
The final satellite in the constellation was launched November 10, 2015.
Visit GPSrChive GAGAN discussion forum.

SDCM

The Russian System for Differential Corrections and Monitoring is an integral component of GLONASS.
SDCM differentiates itself from other SBAS systems by performing integrity monitoring of both GPS and GLONASS satellites.
Visit GPSrChive SDCM discussion forum.

SNAS

China is currently in the process of developing their Satellite Navigation Augmentation System under the BeiDou program.
Visit GPSrChive SNAS discussion forum.

QZSS

The Quasi-Zenith Satellite System ("Michibiki") is a satellite-based augmentation system (SBAS) developed by the Japanese government.
QZSS primary focus is to enhance the United States operated Global Positioning System (GPS) in the Asia-Oceania regions.
A four satellite QZSS service officially started on November 1, 2018.
A seven satellite QZSS service independent of the United States GPS is planned for 2023.
View available QZSS satellites.
Visit GPSrChive QZSS discussion forum.

SouthPAN

The Southern Positioning Augmentation Network (SouthPAN) is a joint initiative of the Australian and New Zealand governments to provide a Satellite-Based Augmentation System (SBAS) for Australia and New Zealand.
On 26 September 2022, SouthPAN early Open Services became live, with safety-of-life certified SouthPAN services planned for 2028.
SouthPAN is the first SBAS in the Southern Hemisphere.
Visit GPSrChive SouthPAN discussion forum.

Satellite Identification

Have you ever considered what the numbers assigned to each GPS satellite on your Garmin GPSr represent, or how they are determined?

Most global positioning systems use a form of spread-spectrum or code-division multiple access (CDMA) communications where each signal source is modulated by a pseudo-random noise (PRN) code.
The PRN code (along with other encoded sub codes) dithers the L1 carrier (or the coarse-acquisition carrier) of the signal.
All receivers listen on the same L1 frequency, but they sort out the satellite signals by demodulating them according to their PRN encoding.

NMEA

Garmin GPS receivers employing the NMEA 0183 specification assign each GPS satellite signal a unique NMEA identification number based on the satellite PRN number (GPS, Galileo, SBAS) or slot number (GLONASS):

=======	==================	======	=================	==============================
PRN	Standard Assignment	NMEA	Garmin Assignment	Garmin NMEA Conversion
01-32	GPS	01-32	GPS	NMEA = PRN
33-63	GPS
64-96	GBAS	65-88	GLONASS	NMEA = GLONASS Slot Number + 64
97-119	GBAS
120-138	SBAS	33-51	SBAS	NMEA = SBAS PRN - 87
139-158	SBAS Expansion/Testing	52-71	SBAS	NMEA = SBAS PRN - 87
159-210	Future GNSS
E01-E36	Galileo	01-36	Galileo	NMEA = PRN (no "E" prefix)
C01-C60	BeiDou	01-60	BeiDou	NMEA = PRN (no "C" prefix)
I01-I08	NavIC	01-08	NavIC	NMEA = PRN (no "I" prefix)
183-199	QZSS	01-05	QZSS	NMEA = SVN

GNSS Signals and Frequencies

System	Signal	Frequency (MHz)

GPS	L1 C/A	1575.420
	L1C	1575.420
	L2C	1227.600
	L2P	1227.600
	L5	1176.450

GLONASS	L1 C/A	1598.0625 - 1609.3125
	L2C	1242.9375 - 1251.6875
	L2P	1242.9375 - 1251.6875
	L3OC	1202.025

Galileo	E1	1575.420
	E5a	1176.450
	E5b	1207.140
	E5 AltBOC	1191.795
	E6	1278.750

BeiDou	B1l	1561.098
	B2l	1207.140
	B3l	1268.520
	B1C	1575.420
	B2a	1176.450
	B2b	1207.140

NavIC	L5	1176.450

QZSS	L1 C/A	1575.420
	L1C	1575.420
	L1S	1575.420
	L2C	1227.600
	L5	1176.450
	L6	1278.750

SBAS	L1	1575.420
SBAS	L5	1176.450

Satellite Tracking

Track individual GPS, GLONASS, Galileo, BeiDou, NavIC and QZSS satellite locations.

Choose a satellite from the list below to view current status, location and other detailed information.
Compare current satellite locations and the Satellite page on your GPSr.

Clock Types	Orbit Types
RB - Rubidium CS - Cesium PHM - Passive Hydrogen Maser RAFS - Rubidium Atomic Frequency Standard HMAC - Hydrogen Maser Atomic Clock	MEO - Medium Earth Orbit GEO - Geostationary Orbit IGSO - Inclined Geosynchronous Orbit QZO - Quasi Zenith Orbit


PRN	NMEA	System	NORAD	Identification	Notes
01	01	GPS	37753	SVN 63 (Navstar 66) USA-232	(IIF-D2) (2F-2) (L1C/A, L2C, L5) (RB)
02	02	GPS	28474	SVN 61 (Navstar 56) USA-180	(IIR-D1) (2R-13) (L1C/A) (RB)
03	03	GPS	40294	SVN 69 (Navstar 72) USA-258	(IIF-E1) (2F-8) (L1C/A, L2C, L5) (RB) ('Spica')
04	04	GPS	43873	SVN 74 (Navstar 77) USA-289	(III-F4) (3-1) (L1C/A, L2C, L5) (RB) ('Vespucci') First to broadcast operational L1C signal
05	05	GPS	35752	SVN 50 (Navstar 64) USA-206	(IIRM-E3) (2R-21M) (L1C/A, L2C) (RB)
06	06	GPS	39741	SVN 67 (Navstar 70) USA-251	(IIF-D4) (2F-6) (L1C/A, L2C, L5) (RB) ('Rigel')
07	07	GPS	32711	SVN 48 (Navstar 62) USA-201	(IIRM-A4) (2R-19M) (L1C/A, L2C) (RB)
08	08	GPS	40730	SVN 72 (Navstar 74) USA-262	(IIF-C3) (2F-10) (L1C/A, L2C, L5) (CS) ('Antares')
09	09	GPS	40105	SVN 68 (Navstar 71) USA-256	(IIF-F3) (2F-7) (L1C/A, L2C, L5) (RB) ('Capella')
10	10	GPS	41019	SVN 73 (Navstar 75) USA-265	(IIF-E2) (2F-11) (L1C/A, L2C, L5) (RB) ('Altair')
11	11	GPS	48859	SVN 78 (Navstar 81) USA-319	(III-D5) (3-5) (L1C/A, L2C, L5) (RB) ('Neil Armstrong')
12	12	GPS	29601	SVN 58 (Navstar 59) USA-192	(IIRM-B4) (2R-16M) (L1C/A, L2C) (RB)
13	13	GPS	24876	SVN 43 (Navstar 43) USA-132	(IIR-F6) (2R-2) (L1C/A) (RB)
14	14	GPS	46826	SVN 77 (Navstar 80) USA-309	(III-B6) (3-4) (L1C/A, L2C, L5) (RB) ('Sacagawea')
15	15	GPS	32260	SVN 55 (Navstar 60) USA-196	(IIRM-F2) (2R-17M) (L1C/A, L2C) (RB)
16	16	GPS	27663	SVN 56 (Navstar 51) USA-166	(IIR-B1) (2R-8) (L1C/A) (RB)
17	17	GPS	28874	SVN 53 (Navstar 57) USA-183	(IIRM-C4) (2R-14M) (L1C/A, L2C) (RB)
18	18	GPS	44506	SVN 75 (Navstar 78) USA-293	(III-D6) (3-2) (L1C/A, L2C, L5) (RB) ('Magellan')
19	19	GPS	28190	SVN 59 (Navstar 54) USA-177	(IIR-C5) (2R-11) (L1C/A) (RB)
20	20	GPS	26360	SVN 51 (Navstar 47) USA-150	(IIR-E4) (2R-4) (L1C/A) (RB)
21	21	GPS	27704	SVN 45 (Navstar 52) USA-168	(IIR-D3) (2R-9) (L1C/A) (RB)
22	22	GPS	26605	SVN 41 (Navstar 49) USA-154	(IIR-F5) (2R-6) (L1C/A) (RB)
23	23	GPS	45854	SVN 76 (Navstar 79) USA-304	(III-E5) (3-3) (L1C/A, L2C, L5) (RB) ('Matthew Henson')
24	24	GPS	38833	SVN 65 (Navstar 67) USA-239	(IIF-A1) (2F-3) (L1C/A, L2C, L5) (CS) ('Arcturus')
25	25	GPS	36585	SVN 62 (Navstar 65) USA-213	(IIF-B2) (2F-1) (L1C/A, L2C, L5) (RB) ('Polaris') First to broadcast operational L5 signal
26	26	GPS	40534	SVN 71 (Navstar 73) USA-260	(IIF-B5) (2F-9) (L1C/A, L2C, L5) (RB) ('Deneb')
27	27	GPS	39166	SVN 66 (Navstar 68) USA-242	(IIF-C2) (2F-4) (L1C/A, L2C, L5) (RB) ('Vega')
28	28	GPS	55268	SVN 79 (Navstar 82) USA-343	(III-A6) (3-6) (L1C/A, L2C, L5) (RB) ('Amelia Earhart')
29	29	GPS	32384	SVN 57 (Navstar 61) USA-199	(IIRM-C1) (2R-18M) (L1C/A, L2C) (RB)
30	30	GPS	39533	SVN 64 (Navstar 69) USA-248	(IIF-A3) (2F-5) (L1C/A, L2C, L5) (RB) ('Canopus')
31	31	GPS	29486	SVN 52 (Navstar 58) USA-190	(IIRM-A2) (2R-15M) (L1C/A, L2C) (RB)
32	32	GPS	41328	SVN 70 (Navstar 76) USA-266	(IIF-F1) (2F-12) (L1C/A, L2C, L5) (RB) ('Betelgeuse')

PRN	NMEA	System	NORAD	Identification	Notes

121	34	SBAS	44624	Eutelsat 5WB	(5° W) (APR 2024)
122	35	SouthPAN	28628	Inmarsat 4-F1	(143.5° E) (L1, L5) (JAN 2023) First SBAS in southern hemisphere
123	36	EGNOS	39617	Astra 5B	(31.5° E) (NOV 2021)
125	38	SDCM	38977	LUCH-5B	(16° W) (DEC 2021)
126	39	EGNOS	28899	Inmarsat 4-F2 (IOR-W)	(63.9° E) (APR 2023)
127	40	GAGAN	37605	GSAT-8	(55° E) (JUN 2030)
128	41	GAGAN	38779	GSAT-10	(83° E) (JUN 2030)
129	42	MSAS	42917	QZS-3 (Michibiki-3)	(127° E) (SEP 2029) (SVN = 003) (Multi PRN Broadcast)
130	43	SNAS	36287	BDSBAS (G1)	(140° E) (AUG 2030) (BDS-3) (B1C, B2a)
131	44	WAAS	41589	Eutelsat 117 West B	(117° W) (MAR 2028)
132	52	GAGAN	41028	GSAT-15	(93.5° E) (NOV 2025)
133	46	WAAS	42709	SES-15	(129° W) (OCT 2029)
134	47	KAAS	52904	MEASAT-3D	(91.5° E) Launched 23JUN22 (gpsworld)
135	48	WAAS	46114	Galaxy 30	(125° W) (JUL 2029)
136	49	EGNOS	38652	SES-5	(5° E) (NOV 2021) (a.k.a. Sirius 5 or Astra 4B)
137	50	MSAS	42917	QZS-3 (Michibiki-3)	(127° E) (SEP 2029) (SVN = 003) (Multi PRN Broadcast)
138	51	WAAS	28868	Anik F1-R	(107.3° W) (JUL 2022)
140	53	SDCM	39727	LUCH-5V	(95° E) (DEC 2021)
141	54	SDCM	37951	LUCH-5A	(167° E) (DEC 2021)
143	56	SNAS	36590	BDSBAS (G3)	(110.5° E) (AUG 2030) (BDS-3) (B1C, B2a)
144	57	SNAS	34779	BDSBAS (G2)	(80° E) (AUG 2030) (BDS-3) (B1C, B2a)

Slot	NMEA	System	NORAD	Identification	Notes

01	65	GLONASS	36111	730 (COSMOS 2456)	(GN 65) (I) (M) (G1C, G2C) (CS)
02	66	GLONASS	39155	747 (COSMOS 2485)	(GN 66) (I) (M) (G1C, G2C) (CS)
03	67	GLONASS	37867	744 (COSMOS 2476)	(GN 67) (I) (M) (G1C, G2C) (CS)
04	68	GLONASS	44850	759 (COSMOS 2544)	(GN 68) (I) (M)
05	69	GLONASS	43508	756 (COSMOS 2527)	(GN 69) (I) (M) (G1C, G2C) (CS)
06	70	GLONASS	36112	733 (COSMOS 2457)	(GN 70) (I) (M) (G1C, G2C) (CS)
07	71	GLONASS	37868	745 (COSMOS 2477)	(GN 71) (I) (M) (G1C, G2C) (CS)
08	72	GLONASS	37869	743 (COSMOS 2475)	(GN 72) (I) (M) (G1C, G2C) (CS)
09	73	GLONASS	40315	702 (COSMOS 2501)	(GN 73) (II) (K1) (G1C, G2C, L3) (CS)
10	74	GLONASS	32395	723 (COSMOS 2436)	(GN 74) (II) (M) (G1C, G2C) (CS)
11	75	GLONASS	46805	705 (COSMOS 2547)	(GN 75) (II) (K1)
12	76	GLONASS	44299	758 (COSMOS 2534)	(GN 76) (II) (M) (G1C, G2C) (CS)
13	77	GLONASS	32393	721 (COSMOS 2434)	(GN 77) (II) (M) (G1C, G2C) (CS)
14	78	GLONASS	42939	752 (COSMOS 2522)	(GN 78) (II) (M) (G1C, G2C) (CS)
15	79	GLONASS	43687	757 (COSMOS 2529)	(GN 79) (II) (M) (G1C, G2C) (CS)
16	80	GLONASS	54377	761 (COSMOS 2564)	(GN 80) (II) (M) (G1C, G2C) (CS)
17	81	GLONASS	41330	751 (COSMOS 2514)	(GN 81) (III) (M+) (G1C, G2C) (CS)
18	82	GLONASS	39620	754 (COSMOS 2492)	(GN 82) (III) (M) (G1C, G2C) (CS)
19	83	GLONASS	32275	720 (COSMOS 2433)	(GN 83) (III) (M) (G1C, G2C) (CS)
20	84	GLONASS	32276	719 (COSMOS 2432)	(GN 84) (III) (M) (G1C, G2C) (CS)
21	85	GLONASS	40001	755 (COSMOS 2500)	(GN 85) (III) (M+) (G1C, G2C, L3) (CS)
22	86	GLONASS	52984	706 (COSMOS 2557)	(GN 86) (III) (K1)
23	87	GLONASS	36402	732 (COSMOS 2460)	(GN 87) (III) (M) (G1C, G2C) (CS)
24	88	GLONASS	45358	760 (COSMOS 2545)	(GN 88) (III) (M)
25	89	GLONASS	54031	707 (COSMOS 2559)	(GN 89) (III) (K1)

PRN	NMEA	System	NORAD	Identification	Notes

E01	01	Galileo	41550	Galileo 13 (26A)	(GSAT0210) (E1, E5a, E5b, E6) (PHM, RAFS) Declared unusable 31AUG22 (NAGU 2022035)
E02	02	Galileo	41549	Galileo 14 (26B)	(GSAT0211) (E1, E5a, E5b, E6) (PHM, RAFS)
E03	03	Galileo	41860	Galileo 16 (26C)	(GSAT0212) (E1, E5a, E5b, E6) (PHM, RAFS)
E04	04	Galileo	41861	Galileo 17 (26D)	(GSAT0213) (E1, E5a, E5b, E6) (PHM, RAFS)
E05	05	Galileo	41862	Galileo 18 (26E)	(GSAT0214) (E1, E5a, E5b, E6) (PHM, RAFS)
E06	06	Galileo
E07	07	Galileo	41859	Galileo 15 (267)	(GSAT0207) (E1, E5a, E5b, E6) (PHM, RAFS)
E08	08	Galileo	41175	Galileo 11 (268)	(GSAT0208) (E1, E5a, E5b, E6) (PHM, RAFS)
E09	09	Galileo	41174	Galileo 12 (269)	(GSAT0209) (E1, E5a, E5b, E6) (PHM, RAFS)
E10	10	Galileo	49810	Galileo 28 (224)	(GSAT0224) (E1, E5a, E5b, E6) (PHM)
E11	11	Galileo	37846	Galileo-PFM	(GSAT0101) (E1, E5a, E5b, E6) (PHM)
E12	12	Galileo	37847	Galileo-FM2	(GSAT0102) (E1, E5a, E5b, E6) (PHM, RAFS)
E13	13	Galileo	43567	Galileo 24 (2C0)	(GSAT0220) (E1, E5a, E5b, E6) (PHM, RAFS)
E14	14	Galileo	40129	Galileo 6 (262)	(GSAT0202) (E1, E5a, E5b, E6) (PHM, RAFS) Declared unusable 16FEB21 (NAGU 2021008)
E15	15	Galileo	43564	Galileo 25 (2C1)	(GSAT0221) (E1, E5a, E5b, E6) (PHM, RAFS)
E16	16	Galileo
E17	17	Galileo
E18	18	Galileo	40128	Galileo 5 (261)	(GSAT0201) (E1, E5a, E5b, E6) (PHM, RAFS) Declared unusable 16FEB21 (NAGU 2021008)
E19	19	Galileo	38857	Galileo-FM3	(GSAT0103) (E1, E5a, E5b, E6) (PHM)
E20	20	Galileo	38858	Galileo-FM4	(GSAT0104) (E1, E5a, E5b, E6) (PHM, RAFS) Payload power problem 27MAY14 (NAGU 2014014)
E21	21	Galileo	43055	Galileo 19 (2C5)	(GSAT0215) (E1, E5a, E5b, E6) (PHM, RAFS)
E22	22	Galileo	40545	GSAT0204	(GSAT0204) (E1, E5a, E5b, E6) (PHM, RAFS) Removed from service 08DEC17 (NAGU 2017045)
E23	23	Galileo
E24	24	Galileo	40889	Galileo 9 (205)	(GSAT0205) (E1, E5a, E5b, E6) (PHM, RAFS)
E25	25	Galileo	43056	Galileo 20 (2C6)	(GSAT0216) (E1, E5a, E5b, E6) (PHM, RAFS)
E26	26	Galileo	40544	GSAT0203	(GSAT0203) (E1, E5a, E5b, E6) (PHM, RAFS)
E27	27	Galileo	43057	Galileo 21 (2C7)	(GSAT0217) (E1, E5a, E5b, E6) (PHM, RAFS)
E28	28	Galileo
E29	29	Galileo
E30	30	Galileo	40890	Galileo 10 (206)	(GSAT0206) (E1, E5a, E5b, E6) (PHM, RAFS)
E31	31	Galileo	43058	Galileo 22 (2C8)	(GSAT0218) (E1, E5a, E5b, E6) (PHM, RAFS)
E32	32	Galileo
E33	33	Galileo	43565	Galileo 26 (2C2)	(GSAT0222) (E1, E5a, E5b, E6) (PHM, RAFS)
E34	34	Galileo	49809	Galileo 27 (223)	(GSAT0223) (E1, E5a, E5b, E6) (PHM)
E35	35	Galileo
E36	36	Galileo	43566	Galileo 23 (2C9)	(GSAT0219) (E1, E5a, E5b, E6) (PHM, RAFS)

PRN	NMEA	System	NORAD	Identification	Notes

C01	01	BeiDou-2	44231	BeiDou 2 GEO-8	(BDS-2) (B1I, B2I, B3I) (RB) (144.5° E)
C02	02	BeiDou-2	38953	BeiDou 2 GEO-6	(BDS-2) (B1I, B2I, B3I) (RB) (84° E)
C03	03	BeiDou-2	41586	BeiDou 2 GEO-7	(BDS-2) (B1I, B2I, B3I) (RB) (110.5° E)
C04	04	BeiDou-2	37210	BeiDou 2 GEO-4	(BDS-2) (B1I, B2I, B3I) (RB) (160° E)
C05	05	BeiDou-2	38091	BeiDou 2 GEO-5	(BDS-2) (B1I, B2I, B3I) (RB) (58.5° E)
C06	06	BeiDou-2	36828	BeiDou 2 IGSO-1	(BDS-2) (B1I, B2I, B3I) (RB)
C07	07	BeiDou-2	37256	BeiDou 2 IGSO-2	(BDS-2) (B1I, B2I, B3I) (RB)
C08	08	BeiDou-2	37384	BeiDou 2 IGSO-3	(BDS-2) (B1I, B2I, B3I) (RB)
C09	09	BeiDou-2	37763	BeiDou 2 IGSO-4	(BDS-2) (B1I, B2I, B3I) (RB)
C10	10	BeiDou-2	37948	BeiDou 2 IGSO-5	(BDS-2) (B1I, B2I, B3I) (RB)
C11	11	BeiDou-2	38250	BeiDou 2 MEO-3	(BDS-2) (B1I, B2I, B3I) (RB)
C12	12	BeiDou-2	38251	BeiDou 2 MEO-4	(BDS-2) (B1I, B2I, B3I) (RB)
C13	13	BeiDou-2	41434	BeiDou 2 IGSO-6	(BDS-2) (B1I, B2I, B3I) (RB)
C14	14	BeiDou-2	38775	BeiDou 2 MEO-6	(BDS-2) (B1I, B2I, B3I) (RB)
C16	16	BeiDou-2	43539	BeiDou 2 IGSO-7	(BDS-2) (B1I, B2I, B3I) (RB)
C19	19	BeiDou-3	43001	BeiDou 3 MEO-1	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C20	20	BeiDou-3	43002	BeiDou 3 MEO-2	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C21	21	BeiDou-3	43208	BeiDou 3 MEO-3	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C22	22	BeiDou-3	43207	BeiDou 3 MEO-4	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C23	23	BeiDou-3	43581	BeiDou 3 MEO-5	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C24	24	BeiDou-3	43582	BeiDou 3 MEO-6	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C25	25	BeiDou-3	43603	BeiDou 3 MEO-11	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C26	26	BeiDou-3	43602	BeiDou 3 MEO-12	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C27	27	BeiDou-3	43107	BeiDou 3 MEO-7	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C28	28	BeiDou-3	43108	BeiDou 3 MEO-8	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C29	29	BeiDou-3	43245	BeiDou 3 MEO-9	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C30	30	BeiDou-3	43246	BeiDou 3 MEO-10	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C31	31	BeiDou-3S	40549	BeiDou 3 IGSO-1S	(BDS-3S) (H)
C32	32	BeiDou-3	43622	BeiDou 3 MEO-13	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C33	33	BeiDou-3	43623	BeiDou 3 MEO-14	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C34	34	BeiDou-3	43648	BeiDou 3 MEO-15	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C35	35	BeiDou-3	43647	BeiDou 3 MEO-16	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C36	36	BeiDou-3	43706	BeiDou 3 MEO-17	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C37	37	BeiDou-3	43707	BeiDou 3 MEO-18	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C38	38	BeiDou-3	44204	BeiDou 3 IGSO-1	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C39	39	BeiDou-3	44337	BeiDou 3 IGSO-2	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C40	40	BeiDou-3	44709	BeiDou 3 IGSO-3	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C41	41	BeiDou-3	44864	BeiDou 3 MEO-19	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C42	42	BeiDou-3	44865	BeiDou 3 MEO-20	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (RB)
C43	43	BeiDou-3	44793	BeiDou 3 MEO-21	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C44	44	BeiDou-3	44794	BeiDou 3 MEO-22	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C45	45	BeiDou-3	44543	BeiDou 3 MEO-23	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C46	46	BeiDou-3	44542	BeiDou 3 MEO-24	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C48	48	BeiDou-3	58655	BeiDou 3 MEO-26	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C50	50	BeiDou-3	58654	BeiDou 3 MEO-28	(BDS-3) (B1I, B3I, B1C, B2a, B2b) (H)
C56	56	BeiDou-3S	40938	BeiDou 3 IGSO-2S	(BDS-3S) (H)
C57	57	BeiDou-3S	40749	BeiDou 3 MEO-1S	(BDS-3S) (RB)
C58	58	BeiDou-3S	40748	BeiDou 3 MEO-2S	(BDS-3S) (RB)
C59	59	BeiDou-3	43683	BeiDou 3 GEO-1	(BDS-3) (B1I, B3I, B2b) (H) (140° E)
C60	60	BeiDou-3	45344	BeiDou 3 GEO-2	(BDS-3) (B1I, B3I, B2b) (H) (80° E)
C61	61	BeiDou-3	45807	BeiDou 3 GEO-3	(BDS-3) (B1I, B3I, B2b) (H) (110.5° E)
C62	62	BeiDou-3	56564	BeiDou 3 GEO-4	(BDS-3) (B1I, B3I) (H) (160° E)

PRN	NMEA	System	NORAD	Identification	Notes

I01	01	NavIC	39199	IRNSS-1A	(IGSO) (L5, S) (RB) Used only for short message broadcast service following atomic clock failure
I02	02	NavIC	39635	IRNSS-1B	(IGSO) (L5, S) (RB)
I03	03	NavIC	40269	IRNSS-1C	(GEO) (L5, S) (RB) (83° E)
I04	04	NavIC	40547	IRNSS-1D	(IGSO) (L5, S) (RB)
I05	05	NavIC	41241	IRNSS-1E	(IGSO) (L5, S) (RB)
I06	06	NavIC	41384	IRNSS-1F	(GEO) (L5, S) (RB) (32.5° E)
I07	07	NavIC	41469	IRNSS-1G	(GEO) (L5, S) (RB) (129.5° E)
I09	09	NavIC	43286	IRNSS-1I	(IGSO) (L5, S) (RB) Replacement for failed IRNSS-1H (originally intended for IRNSS-1A)

PRN	NMEA	System	NORAD	Identification	Notes

193	01	QZSS	37158	QZS-1 (Michibiki)	(QZO) (L1C/A, L1C, L2C, L5) (RB) (AUG 2025) (SVN=001) Shifted to standby operation 25MAR22 (NAQU 2022059) Terminated 15SEP23 (NAQU 2023134)
194	02	QZSS	42738	QZS-2 (Michibiki-2)	(QZO) (L1C/A, L1C, L2C, L5) (RB) (AUG 2025) (SVN=002)
195	04	QZSS	42965	QZS-4 (Michibiki-4)	(QZO) (L1C/A, L1C, L2C, L5) (RB) (AUG 2025) (SVN=004)
196	05	QZSS	49336	QZS-1R (Michibiki-1R)	(QZO) (L1C/A, L1C, L2C, L5) (RB) (AUG 2025) (SVN=005)
199	03	QZSS	42917	QZS-3 (Michibiki-3)	(GEO) (L1C/A, L1C, L2C, L5) (RB) (AUG 2025) (SVN=003) (127° E) (See MSAS)

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