Direct Initialization of Ultra-Tightly Coupled Weapons using a UTC Assisted Acquisition Process

Significant GPS anti-jam performance improvements for GPS-guided weapons can be achieved through the use of Ultra-Tightly-Coupled (UTC) GPS/inertial integrated systems. However, current UTC processing techniques use conventional code and carrier tracking loops to transition from direct signal acquisition to the UTC mode. This diminishes the benefits that can be achieved by UTC tracking in a jamming environment. Under this proposed SBIR effort we will develop a high A/J direct acquisition mode for UTC signal processing. Our proposed approach, termed UTC Assisted Acquisition, leverages aiding information that is provided to the weapon (Child) from the launch platform (Parent), to allow the weapon's GPS receiver to directly enter the UTC mode. The major innovation of the proposed approach is to use the Parent aiding data to reduce the UTC search space and leverage the UTC processing to use the combined set of satellite signals for acquisition for improved A/J protection. Under Phase II, we will build a prototype UTC-AA Test Bed and demonstrate the improvements possible in A/J robustness and accuracy through simulation and testing. A demonstration will also be performed with a JDAM capable Mission Computer OFP for the F-16 working with Lockheed Martin's System Integration Lab.