(U) Fixed Reception Pattern Antenna (FRPA)/Antenna Electronics (AE-4)

(The effects of any budget/program decisions made since the information was collected during 1997-98 are NOT reflected in the National Security Space Road Map (NSSRM).)

Overview: (U)
(U)  The Fixed Reception Pattern Antenna (FRPA) and Antenna Electronics (AE-4) are used in conjunction to receive signals from the GPS satellites.  They are used in aircraft, on board ship, and in manpacks.

Description: (U)
(U)   Fixed Reception Pattern Antennas (FRPAs) have been developed for aircraft and shipboard use with GPS receivers.  These comprise a single element, omni-directional antenna to receive GPS satellite signals from about five to ten degrees above the horizon and up.  The FRPA-3 is used for aircraft applications, the FRPA-GP (a FRPA-3 mounted on a ground plane) is used for shipboard applications, and the FRPA-4  is used with the Manpack.  

(U)  Antenna Electronics (AEs) are used for three basic purposes:  to amplify the incoming GPS signal to support longer cable runs to the GPS receiver;  to convert the incoming GPS signal to the required Intermediate Frequency (IF); and to process adaptively the signal received from a Controlled Reception Pattern Antenna (CRPA) to reduce the effectiveness of any received jamming signals (AE-1/AE-1A only).  Current models are the AE-1/AE-1A, which operates with the CRPA-2, and the AE-4, which is used with the FRPA-3 and FRPA-GP.

User Impact: (U)
(U) The FRPA/AE is used to receive GPS signals and route them to GPS receivers in airborne and ship applications providing highly accurate, all weather navigation and timing information to the aircraft allowing more precise flight patterns, rendezvous, and weapons delivery.

Programmatics: (U)
(U) Operational.

(U) Organizations and Funding:
	(U) Air Force.
		(U) PE351654F

Related Initiatives: (U)
(U) CRPA/AE-1, GAS-1 CRPA/AE, GPS Block IIA, GPS Block IIF, GPS Block IIR

Related Requirements: (U)
(U) None.

Related Categories: (U)
(U) Antennae

Road Map Placements: (U)
(U) NAVIGATION.

Lead Office: (U)
(U) Air Force.

Date of Information: (U)
01 November 1997

(The effects of any budget/program decisions made since the information was collected during 1997-98 are NOT reflected in the National Security Space Road Map (NSSRM).)