CA2252158A1 - A method of automatically determining the position of vehicles - Google Patents
A method of automatically determining the position of vehicles Download PDFInfo
- Publication number
- CA2252158A1 CA2252158A1 CA002252158A CA2252158A CA2252158A1 CA 2252158 A1 CA2252158 A1 CA 2252158A1 CA 002252158 A CA002252158 A CA 002252158A CA 2252158 A CA2252158 A CA 2252158A CA 2252158 A1 CA2252158 A1 CA 2252158A1
- Authority
- CA
- Canada
- Prior art keywords
- data
- vehicles
- automatically determining
- service radio
- information bytes
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/03—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
- G01S19/07—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/0009—Transmission of position information to remote stations
- G01S5/009—Transmission of differential positioning data to mobile
Abstract
A method of automatically determining the position of vehicles by means of the DGPS (Differential Global Positioning System) is proposed, whereby at least one vehicle in the local public passenger traffic and one fixed station receive GPS data which characterize the distance to GPS satellites, where the data of the fixed station are transmitted as correction data 8 via service radio telegrams 5 to the mobile station 6 in the vehicles 1, and where the transmission of the correction data 8 takes place through expansion of the service radio telegrams 5 by at least one information byte 9.
Description
CA 022~21~8 1998-11-2~
A METHOD OF AUTOMATICALLY DETERMINING
THE POSITION OF VEHICLES
Field of the Invention The invention is directed to a method of automatically determining the position of vehicles by means of a DGPS (~irrerelltial Global _ositioning System) wherein at least one vehicle in the OPNV (~ocal Public Passenger Traffic) and a fixed station (2) receive 5 GPS (5~lobal _ositioning Systems) data, which characterize the distance to GPS satellites, where the GPS data from the fixed station are trAn~mitte~ as correction data via service radio telegrams to the mobile stations in the vehicles, and wherein the tr~n~mi~sion of the correction data takes place through expansion of the service radio telegrams by at least one information byte.
10 Description of the Prior Art From the technical article "AVLS - A system for automatically dete~ g the position of vehicles" by A. Bethm~nn et al., 1994, Alcatel SEL, Stuttgart, it is known to use a number of position determination possibilities to compute the exact location of vehicles. The GPS Global Positioning System is used to that end for example. The15 system comprises 25 satellites, not all of which are still active however. The accuracy of the location is approximately 100 meters for private users. The determination of the position is based on the direct distance measurement between satellites and vehicular receiver by means of the half-wave time delay measurement method with synchronized time reference. Inaccuracies must be expected, because ionospheric disturbances affect 20 the signal propagation time, and atmospheric disturbances and damping limit the availability of the signal. Multipath reception furthermore causes positioning errors, particularly in a city environment. Signal shading is possible in tunnels.
The problems with the global positioning system are partly avoided when a differential method is used. A GPS receiver is installed in a known reference location.
25 This reference receiver is able to determine very accurately the distance from its location to the satellites. In the vehicles these ~ t~n~es are now compared with the distances measured in the vehicles. This determines the errors in the distance measurement and thereby improves the result of the measurement. With this method the positioning .
accuracy can be increased to 10 meters in the horizontal direction. The above-cited technical article also discusses the type of data tran.cmi~sion between the fixed station and the mobile devices. The use of (PMR = _rivate Mobile Radio) service radio for communication by the mobile stations with the fixed station is discussed as an example of 5 a solution. Service radio networks are widely used, particularly in local public traffic, but their data capacity cannot be expanded to any desired extent.
Summary of the Invention Therefore the object exists to integrate the advantages of the dirrer~lllial position determination GPS into existing motor pools by using existing service radio 10 networks for exch~nging the relevant data.
The method of the invention is a method of automatically determinin~ the position of vehicles by means of a DGPS method (Dirr~,ellLial _lobal _ositioningSystem), whereby at least one vehicle in the OPNV (~ocal _ublic _assenger Traffic) and a fixed station receive GPS ~lobal _ositioning Systems) data, which characterize the 15 ~ t~nre to GPS satellites, where the GPS data from the fixed station are tr~n~mitted as correction data via service radio telegrams to the mobile stations in the vehicles, and wherein the tr~n~mi~sion of the correction data takes place through expansion of the service radio telegrams by at least one information byte. This method has the advantage that by including the GPS data of the fixed station in a service radio telegram, the 20 correction data needed to compute an accurate position are tr~n~mitte~ to the mobile station. The system to carry out the method requires no replacement of the already existing infrastructure and no change in the provided service radio protocols. The relevant correction data are redirected inside of individual information bytes to the mobile station in the vehicle.
It is particularly advantageous that the method can be built without great expense into the quasi norm 420 of the VDV (Association of German Traffic Ellll~lel~eurs).
CA 022~21~8 1998-11-2~
.
It is furthermore possible to insert in a simple manner up to 15 additional information bytes into the data frame of the structure provided by the VDV protocol. It is an advantage that an information byte is transmitted by sign~lling whether correction data are sent by a satellite, and if so by one or by two satellites. In addition, the entire 5 information required to correct the position, such as alignment rates, times, scale factors etc., is tr~n~mitted in the information bytes.
Description of the Drawin~s An embodiment of the invention is illustrated in Figure 1 and is explained in greater detail in Figures 2 and 3, wherein:.
FIG. 1 schematically illustrates the construction of a communi~ations network;
FIG. 2 illustrates the data frame structure of the service radio telegram; and FIG. 3 illustrates the data structure of the information bytes.
Detailed Description of the Preferred Embodiment FIG. 1 illustrates an example of two vehicles 1 which are in touch with the fixed station 2 via mobile stations 6. The connection to the fixed station 2 is established via service radio telegrams 5. In addition the vehicles 1 contain mobile stations 6 which are used to receive the positioning signals 4b from the satellites 3. The central station 2 receives the positioning signals 4b from the satellites 3. To be able to utilize the 20 advantages of the dirrerelllial GPS method, the central station 2 evaluates the GPS signals 4a it receives, and sends these signals to the vehicles 1 via the service Mdio telegrams 5.
In this way the mobile stations 6 in the vehicles receive two complete data sets for determination of the position, namely the data 4b they measured themselves, as well as the correction data 8 that were tr~ncmitted by the central station 2 via the service radio 25 channel. The correction data 8 are essentially identical to the position data 4a measured by the central station, but since the service radio telegrams cannot be of any desired size, they must be tr~n.~mitt~d in several units and thus represent a special prepared form of the data set. If both complete data sets 4a and 4b are available in the vehicle, the mobile CA 022~21~8 1998-11-2~
station 6 can undertake a differential computation and determine the position of the vehicle with great accuracy.
The service radio telegram 5 m~int~inc the communication between the mobile and the fixed station and is used to transmit the GPS data 4a of the fixed station. The 5 service radio telegram 5 comprises a data frame 10 which includes several sections. The data frame begins with a synchronization pattern 11 that contains inforrnation for syncl~ol~ing the fixed and the mobile station. A sequence of information bytes 9follows, the first three of which are firmly defined and cannot be loaded with additional information. By contrast the fourth information byte, as well as every further information 10 byte that can be inserted into the data frame after bit location 13, is available for transporting information. Two control bytes 12 termin~te the data frame. A stuffing bit is tr~n.cmittecl between each of the individual information bytes 9. The two CRC (~yclic E~ed~ln~l~n~y Check) control bytes 12 are used to check the quality of the data channel and call attention to faulty tr~ncmi.c.cions. The information bytes 1 to 4 are used to transmit 15 information about the type of service radio telegram and the length of the telegram. It is possible to insert 15 additional information bytes which follow the four originally deflned information bytes.
FIG. 3 provides details about the structure of the information bytes with the consecutive numbers of 1 to 19. The first three information bytes transmit the TY
20 information about the type of telegram as well as TL, the length of the telegram. Various information is inserted into the subsequent information bytes 9:
DT (~2ay Type) defines the actual data HR ~ouE of actual time), MI (~ nutes of actual time), SC (~econds of actual time), where all of these data are used for tuning the actual times between the fixed and the mobile station. The eighth information byte 25 includes an information NR (~umbe_ of satellites) which within a length of 2 bits signals whether data from one satellite or two satellites or no satellites are being tr~ncmitted.
The next-in-line data MZC (~odified Z-Count) include data for both of the possible satellite data that can be tr~ncmitted with this telegram. These data contain the reference CA 022~21~8 1998-11-2~
to the GPS time with a scaling factor of 0.6 seconds. The tenth information byte uses SF
(~cale _actor) to transmit the scaling factor for both the _seudo Range Correction (PRC) as well as the Range Rate Correction (RRC). The information SID (Satellite ~2) is used to identify the satellite. Subsequently PRC and RRC are used to transmit the data content S of the sighted satellite. The IOD field is located in the fourteenth information byte and contains information about the ephemeral position of the satellite. The data of the second satellite are transmitted in the fifteenth to the nineteenth information bytes, analogously to the first satellite. After tr~ncmitting a maximum of 6 service radio telegrams structured as illustrated in FIG. 3, the complete reference data from 12 satellites have been 10 tr~ncmitted to the mobile station.
The data structure illustrated in FIG. 3 represents one possible data structure.It is of course also possible to transmit the required information and data in a different sequence and with a different structure, but the boundary conditions of the VDV protocol must be m~int~in.o~i.
The enormous advantage of the proposed method is its simple integration into already existing service radio networks which observe the VDV standard. The additional information can be included in a simple manner, while any further processing takes place in the mobile station itself by means of an intelligent GPS receiver.
A METHOD OF AUTOMATICALLY DETERMINING
THE POSITION OF VEHICLES
Field of the Invention The invention is directed to a method of automatically determining the position of vehicles by means of a DGPS (~irrerelltial Global _ositioning System) wherein at least one vehicle in the OPNV (~ocal Public Passenger Traffic) and a fixed station (2) receive 5 GPS (5~lobal _ositioning Systems) data, which characterize the distance to GPS satellites, where the GPS data from the fixed station are trAn~mitte~ as correction data via service radio telegrams to the mobile stations in the vehicles, and wherein the tr~n~mi~sion of the correction data takes place through expansion of the service radio telegrams by at least one information byte.
10 Description of the Prior Art From the technical article "AVLS - A system for automatically dete~ g the position of vehicles" by A. Bethm~nn et al., 1994, Alcatel SEL, Stuttgart, it is known to use a number of position determination possibilities to compute the exact location of vehicles. The GPS Global Positioning System is used to that end for example. The15 system comprises 25 satellites, not all of which are still active however. The accuracy of the location is approximately 100 meters for private users. The determination of the position is based on the direct distance measurement between satellites and vehicular receiver by means of the half-wave time delay measurement method with synchronized time reference. Inaccuracies must be expected, because ionospheric disturbances affect 20 the signal propagation time, and atmospheric disturbances and damping limit the availability of the signal. Multipath reception furthermore causes positioning errors, particularly in a city environment. Signal shading is possible in tunnels.
The problems with the global positioning system are partly avoided when a differential method is used. A GPS receiver is installed in a known reference location.
25 This reference receiver is able to determine very accurately the distance from its location to the satellites. In the vehicles these ~ t~n~es are now compared with the distances measured in the vehicles. This determines the errors in the distance measurement and thereby improves the result of the measurement. With this method the positioning .
accuracy can be increased to 10 meters in the horizontal direction. The above-cited technical article also discusses the type of data tran.cmi~sion between the fixed station and the mobile devices. The use of (PMR = _rivate Mobile Radio) service radio for communication by the mobile stations with the fixed station is discussed as an example of 5 a solution. Service radio networks are widely used, particularly in local public traffic, but their data capacity cannot be expanded to any desired extent.
Summary of the Invention Therefore the object exists to integrate the advantages of the dirrer~lllial position determination GPS into existing motor pools by using existing service radio 10 networks for exch~nging the relevant data.
The method of the invention is a method of automatically determinin~ the position of vehicles by means of a DGPS method (Dirr~,ellLial _lobal _ositioningSystem), whereby at least one vehicle in the OPNV (~ocal _ublic _assenger Traffic) and a fixed station receive GPS ~lobal _ositioning Systems) data, which characterize the 15 ~ t~nre to GPS satellites, where the GPS data from the fixed station are tr~n~mitted as correction data via service radio telegrams to the mobile stations in the vehicles, and wherein the tr~n~mi~sion of the correction data takes place through expansion of the service radio telegrams by at least one information byte. This method has the advantage that by including the GPS data of the fixed station in a service radio telegram, the 20 correction data needed to compute an accurate position are tr~n~mitte~ to the mobile station. The system to carry out the method requires no replacement of the already existing infrastructure and no change in the provided service radio protocols. The relevant correction data are redirected inside of individual information bytes to the mobile station in the vehicle.
It is particularly advantageous that the method can be built without great expense into the quasi norm 420 of the VDV (Association of German Traffic Ellll~lel~eurs).
CA 022~21~8 1998-11-2~
.
It is furthermore possible to insert in a simple manner up to 15 additional information bytes into the data frame of the structure provided by the VDV protocol. It is an advantage that an information byte is transmitted by sign~lling whether correction data are sent by a satellite, and if so by one or by two satellites. In addition, the entire 5 information required to correct the position, such as alignment rates, times, scale factors etc., is tr~n~mitted in the information bytes.
Description of the Drawin~s An embodiment of the invention is illustrated in Figure 1 and is explained in greater detail in Figures 2 and 3, wherein:.
FIG. 1 schematically illustrates the construction of a communi~ations network;
FIG. 2 illustrates the data frame structure of the service radio telegram; and FIG. 3 illustrates the data structure of the information bytes.
Detailed Description of the Preferred Embodiment FIG. 1 illustrates an example of two vehicles 1 which are in touch with the fixed station 2 via mobile stations 6. The connection to the fixed station 2 is established via service radio telegrams 5. In addition the vehicles 1 contain mobile stations 6 which are used to receive the positioning signals 4b from the satellites 3. The central station 2 receives the positioning signals 4b from the satellites 3. To be able to utilize the 20 advantages of the dirrerelllial GPS method, the central station 2 evaluates the GPS signals 4a it receives, and sends these signals to the vehicles 1 via the service Mdio telegrams 5.
In this way the mobile stations 6 in the vehicles receive two complete data sets for determination of the position, namely the data 4b they measured themselves, as well as the correction data 8 that were tr~ncmitted by the central station 2 via the service radio 25 channel. The correction data 8 are essentially identical to the position data 4a measured by the central station, but since the service radio telegrams cannot be of any desired size, they must be tr~n.~mitt~d in several units and thus represent a special prepared form of the data set. If both complete data sets 4a and 4b are available in the vehicle, the mobile CA 022~21~8 1998-11-2~
station 6 can undertake a differential computation and determine the position of the vehicle with great accuracy.
The service radio telegram 5 m~int~inc the communication between the mobile and the fixed station and is used to transmit the GPS data 4a of the fixed station. The 5 service radio telegram 5 comprises a data frame 10 which includes several sections. The data frame begins with a synchronization pattern 11 that contains inforrnation for syncl~ol~ing the fixed and the mobile station. A sequence of information bytes 9follows, the first three of which are firmly defined and cannot be loaded with additional information. By contrast the fourth information byte, as well as every further information 10 byte that can be inserted into the data frame after bit location 13, is available for transporting information. Two control bytes 12 termin~te the data frame. A stuffing bit is tr~n.cmittecl between each of the individual information bytes 9. The two CRC (~yclic E~ed~ln~l~n~y Check) control bytes 12 are used to check the quality of the data channel and call attention to faulty tr~ncmi.c.cions. The information bytes 1 to 4 are used to transmit 15 information about the type of service radio telegram and the length of the telegram. It is possible to insert 15 additional information bytes which follow the four originally deflned information bytes.
FIG. 3 provides details about the structure of the information bytes with the consecutive numbers of 1 to 19. The first three information bytes transmit the TY
20 information about the type of telegram as well as TL, the length of the telegram. Various information is inserted into the subsequent information bytes 9:
DT (~2ay Type) defines the actual data HR ~ouE of actual time), MI (~ nutes of actual time), SC (~econds of actual time), where all of these data are used for tuning the actual times between the fixed and the mobile station. The eighth information byte 25 includes an information NR (~umbe_ of satellites) which within a length of 2 bits signals whether data from one satellite or two satellites or no satellites are being tr~ncmitted.
The next-in-line data MZC (~odified Z-Count) include data for both of the possible satellite data that can be tr~ncmitted with this telegram. These data contain the reference CA 022~21~8 1998-11-2~
to the GPS time with a scaling factor of 0.6 seconds. The tenth information byte uses SF
(~cale _actor) to transmit the scaling factor for both the _seudo Range Correction (PRC) as well as the Range Rate Correction (RRC). The information SID (Satellite ~2) is used to identify the satellite. Subsequently PRC and RRC are used to transmit the data content S of the sighted satellite. The IOD field is located in the fourteenth information byte and contains information about the ephemeral position of the satellite. The data of the second satellite are transmitted in the fifteenth to the nineteenth information bytes, analogously to the first satellite. After tr~ncmitting a maximum of 6 service radio telegrams structured as illustrated in FIG. 3, the complete reference data from 12 satellites have been 10 tr~ncmitted to the mobile station.
The data structure illustrated in FIG. 3 represents one possible data structure.It is of course also possible to transmit the required information and data in a different sequence and with a different structure, but the boundary conditions of the VDV protocol must be m~int~in.o~i.
The enormous advantage of the proposed method is its simple integration into already existing service radio networks which observe the VDV standard. The additional information can be included in a simple manner, while any further processing takes place in the mobile station itself by means of an intelligent GPS receiver.
Claims (10)
1. A method of automatically determining the position of vehicles (1) by means of a DGPS method (Differential Global Positioning System), whereby at least one vehicle (1) in the öPNV (Local Public Passenger Traffic) and a fixed station (2) receive GPS (Global Positioning Systems) data, which characterize the distance to GPS
satellites (3), where the GPS data (4a) from the fixed station are transmitted as correction data (8) via service radio telegrams (5) to the mobile stations (6) in the vehicles (1), characterized in that the transmission of the correction data (8) takes place through expansion of the service radio telegrams (5) by at least one information byte (9).
satellites (3), where the GPS data (4a) from the fixed station are transmitted as correction data (8) via service radio telegrams (5) to the mobile stations (6) in the vehicles (1), characterized in that the transmission of the correction data (8) takes place through expansion of the service radio telegrams (5) by at least one information byte (9).
2. A method of automatically determining the position of vehicles as claimed in claim 1, characterized in that the service radio telegrams (5) are constituted in accordance with the norms of the VDV (Association of German Traffic Entrepreneurs) protocols.
3. A method of automatically determining the position of vehicles as claimed in claim 2, characterized in that up to 16 additional information bytes (9) are inserted into the data frames (10) of the service radio telegrams (5).
4. A method of automatically determining the position of vehicles as claimed in claim 3, characterized in that the additional information bytes (9) contain the GPS data (4a) received by the fixed station (2) from at least one satellite (3).
5. A method of automatically determining the position of vehicles (1) as claimed in claim 4, characterized in that one of the information bytes (9) signals whether correction data and if-yes data are transmitted by one or by two satellites (3).
6. A method of automatically determining the position of vehicles (1) as claimed in claim 5, characterized in that data for aligning, dating, scaling as well as the position data are transmitted in the information bytes (9).
7. A method of automatically determining the position of vehicles as claimed in claim 1, characterized in that up to 16 additional information bytes (9) are inserted into the data frames (10) of the service radio telegrams (5).
8. A method of automatically determining the position of vehicles as claimed in claim 1, characterized in that the additional information bytes (9) contain the GPS data (4a) received by the fixed station (2) from at least one satellite (3).
9. A method of automatically determining the position of vehicles (1) as claimed in claim 1, characterized in that one of the information bytes (9) signals whether correction data and if-yes data are transmitted by one or by two satellites (3).
10. A method of automatically determining the position of vehicles (1) as claimed in claim 1, characterized in that data for aligning, dating, scaling as well as the position data are transmitted in the information bytes (9).
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19752361A DE19752361A1 (en) | 1997-11-26 | 1997-11-26 | Method for automatically determining the position of vehicles |
| DE19752361.7 | 1997-11-26 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2252158A1 true CA2252158A1 (en) | 1999-05-26 |
Family
ID=7849851
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002252158A Abandoned CA2252158A1 (en) | 1997-11-26 | 1998-11-25 | A method of automatically determining the position of vehicles |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US6195038B1 (en) |
| EP (1) | EP0919827A3 (en) |
| AU (1) | AU9241198A (en) |
| CA (1) | CA2252158A1 (en) |
| DE (1) | DE19752361A1 (en) |
| SG (1) | SG77659A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6564146B1 (en) * | 2000-01-24 | 2003-05-13 | The United States Of America As Represented By The Secretary Of The Navy | Tracking system for providing position information |
| DE10004421A1 (en) * | 2000-02-02 | 2001-08-09 | Bosch Gmbh Robert | Radio identification system and method |
| US20030054329A1 (en) * | 2001-09-14 | 2003-03-20 | Springett David Roy | Portable computer classroom with high speed two-way network access |
| CN105405313A (en) * | 2015-11-21 | 2016-03-16 | 广西南宁至简至凡科技咨询有限公司 | Bus automatic stop-reporting system based on GPS positioning |
| CN105448126A (en) * | 2015-11-21 | 2016-03-30 | 广西南宁至简至凡科技咨询有限公司 | Bus-mounted GPS intelligent stop reporting system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5689431A (en) * | 1995-04-18 | 1997-11-18 | Leading Edge Technologies, Inc. | Golf course yardage and information system |
-
1997
- 1997-11-26 DE DE19752361A patent/DE19752361A1/en not_active Withdrawn
-
1998
- 1998-10-23 EP EP98440233A patent/EP0919827A3/en not_active Ceased
- 1998-11-17 AU AU92411/98A patent/AU9241198A/en not_active Abandoned
- 1998-11-24 US US09/199,110 patent/US6195038B1/en not_active Expired - Lifetime
- 1998-11-25 CA CA002252158A patent/CA2252158A1/en not_active Abandoned
- 1998-11-26 SG SG1998005000A patent/SG77659A1/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| EP0919827A3 (en) | 2000-02-23 |
| DE19752361A1 (en) | 1999-05-27 |
| US6195038B1 (en) | 2001-02-27 |
| SG77659A1 (en) | 2001-01-16 |
| EP0919827A2 (en) | 1999-06-02 |
| AU9241198A (en) | 1999-06-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |