was subcontracted by AlliedSignal to provide the guidance software
upgrade for the Vandal EER (MQM-8) aerial target. The Navy
Threats and Targets Division based in Pt. Mugu required the Vandal
target upgrade to include an autonomous guidance system based
on GPS. On-board GPS positioning would alleviate the dependence
on ground based radar guidance, and decrease operational cost.
SVC provided input into the selection and evaluation of the GPS
sensor, and provided the software to integrate the GPS and inertial
sensor in the existing guidance system.
challenging aspect to the program was the combination of high-dynamic
launch conditions and severe vibration environment. Most
standard GPS receivers can only track up to around 7 g’s without
the benefit of inertial aiding. With inertial aiding, most
GPS receivers specify a 12 to 15 g limit. Off the rail,
the Vandal accelerates at 15 g’s and there was great concern over
finding a GPS receiver that could track in this environment.
receiver was identified that uses carrier-phase aiding in the
tracking loop extending the dynamic capability to 20 g’s (spec)
without the need for inertial aiding. Space Vector assisted
in the validation of the receiver under high dynamics by developing
and performing the GPS constellation simulator test plan.
The receiver was further validated with sled tests exceeding 20
g’s, and a very successful flight test of the receiver on the