NUMBER OF PARTICIPANTS

system. Areas that have been improved under the Link-16 system include the following: Number of Participants Track Numbers Track Quality Track Identification Friendly Status Granularity of Measurement Relative Navigation Electronic Warfare Land Points and Tracks NUMBER OF PARTICIPANTS. —The number of units that can participate in a Link-16 net has been increased dramatically over that of Link-11. The JTIDS Unit number, or JU, is a five-digit octal number from 00001 to 77777. This allows for a maximum of 32,766 possible JUs. Addresses 00001 to 00177 are normally assigned to units that have the need and capability to participate in both Link-16 and Link-11. When a unit participates in both Link-11 and Link-16, it must use the same address on both links. For example, Link-16 JU 00043 is the same as Link-11 PU 043. TRACK NUMBERS. —Link-l6 replaces the old four-digit (octal) Link-11 track numbers with a five- character alphanumeric track number. The track number can be within the range 00001 to 77777 (octal) or 0A000 through ZZ777. This allows for a maximum of 524,284 track numbers, compared with the 4,092 available with Link-11. One reason for the need for the additional track number is that Link-16 cannot operate in the track number pool mode, in which a common pool of track numbers is shared by several PUs. Every JU must be assigned a unique block of track numbers. To maintain interoperability with Link-11, Link-16 track numbers 00200 through 07777 designate the same track as Link-11 track numbers 0200 through 7777. TRACK QUALITY. —The Track Quality (TQ) value used by Link-16 relates to the accuracy of the reported position of the track. The TQ has a range of 0 to 15. To achieve the highest track quality, the track must be within 50 feet of the reported position. Link-11 uses the update rate to determine track quality. Using Link-11, a track that is reported by a PU at every interrogation is usually assigned a TQ of 7. Therefore, a Link-11 air track with a TQ of 7 can be more than 3 nautical miles from its reported position. TRACK IDENTIFICATION. —The Link-16 system greatly expands the information that is reported with Track Identification (ID). The new ID reports include fields for platform, activity, specific type, and nationality of the track. Additional provisions have also been added to identify a track as “Neutral,” and the Unknown Assumed Enemy ID is changed to “Suspect.” FRIENDLY STATUS. —The Link-16 system also provides for more detailed status reports from friendly aircraft. The following fields are added to Link-16 friendly status reports: equipment status, ordnance inventory, radar and missile channels, fuel available for transfer, gun capability, and station ETA and ETD. INCREASED GRANULARITY. —Granularity refers to how precisely an item is reported in the link message. Link-16 has made major improvements in the granularity of reports concerning track position, air track speed, altitude, and lines of bearing. LINES AND AREAS. —The Link-16 system allows the reporting of multi-segment lines and areas of all sizes and descriptions. Link-11, for comparison, only allows reports of areas that are limited in size and are circles, ellipses, squares, or rectangles. Link-11 does not have the capability to report lines. 7-7