13.3.3.1  Improved Gridlock

Gridlock alignment is often based on radar, LASER rangefinder or other sensor

observations where bearing and range from a grid reference unit is transformed in

grid coordinates of the force.  This inter  platform alignment technique can introduce

substantial errors in positioning if sensors are not correctly aligned.  By

incorporating a GPS receiver into the sensor, the inter platform alignment can be

greatly improved.

13.3.3.2  Geodetic Gridlock

Present gridlock algorithms provide a relative grid bringing partici pating units into

relative alignment with respect to a common track, without regard to geodetic

(absolute) position or orientation accuracy of the entire grid.  While this serves

current purposes well, advanced tactics and systems will require accurate geodetic

as well as relative alignment of the grid. For instance:

a. Better incorporation of intelligence information (e.g. from other sensors/

subsurface, surface, air and space) using GPS as a common position

reference system

b. Initialization of Long Range Sea/Land attack weapons

c. Maintenance of gridlock under EMCON conditions is a must for modern

anti air warfare systems where units are coordinated in fully automated

way to respond to incoming threats.

13.3.3.3  Sensor Calibration

Improved alignment of search and fire control radar sensors and anti  submarine

warfare sonar sensors by using GPS results in a more accurate weapon delivery.

13.3.3.4  OTHT Operations

In the OTHT arena, extended OTHT threat ranges have increased the necessity to

hand off target track data to participating combatants at longer ranges which  may

not be gridlocked with the local tactical grid.  Furthermore, many of the current

OTHT exercises are conducted during radar EMCON where grid lock updates

cannot be performed. Experience with Harpoon missile OTHT exercises has shown

that significant relative navigation errors can occur under these circumstances and

can lead to false target acquisitions and engage ments between friendly forces. 

With GPS  equipped combatants, such problems can be eliminated and OTHT

tactics can fully exploit the long  range intercept capability of modern

surface to surface missiles.  Use of digital maps, GPS and synthetic information on

the tactical display gives the operator a complete picture of:

a. Own position/course/speed over ground (from GPS)

b. Accurate target position/course/speed

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