INFORMATION AND GUIDANCE ON ALLOCATION OF

ID NUMBERS FOR WORLD DGNSS

 Background

In ITU-R M.823-3, on the technical characteristics of differential transmissions for Global Navigation Satellite Systems (GNSS), IALA was assigned the task of coordinating the allocation of identification (ID) numbers to radio beacon transmitting stations and reference stations. The ID numbers enable the user equipment to identify the station it is receiving and also select particular stations when required. It is essential that the ID numbers be allocated in a way that prevents duplication and ambiguity. A scheme was devised by the IALA Radionavigation Committee, now called ENAV Committee, to achieve this and a procedure was established whereby an administration requiring ID numbers could select them from an assigned block and notify IALA so that the choice of numbers could be checked and confirmed.

IALA also maintains a list of all relevant characteristics of known DGNSS stations, including ID numbers. Input to the master list will be prepared by each Administration. IALA will provide an electronic template to be used for initial entry of station data and subsequent updates to the data as required.

Procedure

To ensure that DGNSS ID numbers are allocated, and the Master Station List is maintained and updated, in a timely and efficient manner, the following procedure has been devised.

1.    Administration refers to the IALA website and selects unused ID numbers from the national or regional block as applicable. If no suitable number appears to be available the template, shown in Table below, should be submitted with a query in place of the ID numbers.

 2.       Administration forwards the template to the IALA Secretariat for action.

     3.      The IALA Secretariat forwards the template within 5 working days to the Chairman of WG5 (PNT) of the ENAV Committee to verify that the ID numbers are appropriate. If inappropriate or no number has been selected then the Chairman of WG5 of the ENAV Committee is liaise with the Administration to resolve the situation.

     4.     The Chairman of WG5 of the ENAV Committee is to return the annotated template to the IALA Secretariat. The IALA Secretariat is to update the Master Station List on the IALA website within 5 working days and notify the Member State of the status of their request.

This procedure is shown in Flow Chart below. The Member States are requested to bring this information to the attention of competent authorities and radio regulatory bodies, so that they become aware of the aforementioned scheme and the necessary procedures are put in place to avoid ambiguity or duplication of ID numbers.

 

[Table] Template for Allocation of DGNSS ID numbers

Field

Attribute

Station name

Max. 9 characters

Transmitting Station ID

Integer, 0-1023

Reference Station (RS)1 ID

Integer, 0-1023

Reference Station (RS)2 ID

Integer, 0-1023

Latitude

DD MM ; North / South

Longitude

DDD MM ; East / West

Nominal Range (Km)

 

Field Strength at Nominal Range (μV/m)

 

Official Operational Status

Test or Preliminary / Fully operational / Not in operation*

Integrity Monitoring

Yes / No

Transmitted Message Types

 

Radio frequency (kHz)

 

Bit rate (bits/s)

 

Datum

WGS-84 / PE90 / Local Datum

* DGNSS station that is no longer in operation will remain on the Master LIST for 6 months from date of   termination of service


[Flow chart]
  Process for Allocation of DGNSS ID Numbers




 

Reference

1. ITU-R M.823-3 “Technical characteristics of differential transmissions for global navigation satellite systems from maritime radio beacons in the frequency band 283.5-315 kHz in Region 1 and 285-325 kHz in Regions 2 and 3” (2006)

2. RTCM 10402.3, RTCM Recommended Standards for Differential GNSS Service (Version 2.3)

3. RTCM 10401.2, Standard for Differential Navstar GPS Reference Stations and Integrity    Monitors (RSIM)

4. IALA Recommendation R-121 On the Performance and Monitoring of DGNSS Services in the Frequency Band 283.5 - 325 kHz (Ed. 2.0, May 2015)