Leveraging Waveforms for Accurate and Secure Time Transfer (WATTR) to Networked GPS Receivers

ABSTRACT:Mayflower proposes an accurate and secure GPS time-aiding service for military receivers in challenged RF environments, namely the Leveraging Waveforms for an Accurate and Secure Time Transfer to Networked GPS Receivers (WATTR) to meet the objectives stated in the solicitation.The Mayflower WATTR solution is a waveform agnostic secure precise time aiding service technology specifically designed for use in challenging RF environments (intentional / unintentional jamming and spoofing) suitable for deployment in a wide range of military as well as commercial applications. The Mayflower WATTR technology makes use of the features in the Data Link and Application layers of a communication network and hence is portable across a multitude of tactical and commercial waveforms. We have implemented and demonstrated some of the functional components of WATTR solution in the Mayflower Tactical MANET Testbed (TMT) and MEADOWS Software Defined Radio (SDR). In the proposed Phase II SBIR program, the Mayflower team will augment and enrich the WATTR technology, test and demonstrate it using both Mayflower TMT and WATTR Prototype System. We will ensure its commercialization in Phase II by working closely with proposed prime contractors, namely Harris and Thales.BENEFIT:Several commercial waveforms require a source of accurate time.For instance, LTE requires accurate time to allow base stations in adjacent cells to sufficiently time-synchronized to perform coordinated beamforming to a set of mobile users; note that coordinated beamforming yields near-optimal downlink transmission rates.Presently, LTE base stations can rely on co-located GPS receivers to obtain accurate time.Given the presence of a GPS jammer (or a spoofer which a C/A code GPS receiver is particularly vulnerable to), these base station would fail to acquire accurate time, resulting in degraded quality or loss of service altogether. The proposed WATTR technology is applicable to these commercial waveforms in that it would provide an alternate source of accurate time to the associated communication infrastructure.For example, in the case of LTE, a base station can maintain accurate time over long periods of GPS denial by employing co-located Chip Scale Atomic Clock (CSAC). We note here that many safety critical applications (e.g., police, firefighters, homeland security) depend upon the commercial wireless communication infrastructure in addition to general public (stock market, home security, transportation, weather alerts, etc.) and hence communication infrastructure has tremendous impact on the public safety and national economy.The U.S Army (PD-PNT) is also considering using commercial smart phone technology (4G LTE) for Assured PNT (APNT) for situation awareness using the rich graphical user interface (GUI) of the smart phones and custom apps developed specifically for the military to interface with military GPS receivers. This approach attempts to address the warfighters expressed concerns of poor graphical user interface of the currently deployed DAGR receivers.If this Army APNT approach moves beyond the R&D phase, the need for secure time transfer using commercial LTE waveform can also be addressed by the Mayflower WATTR technology.