Areas of work

Lead software architect for a GNSS SDR receiver at Northrop Grumman. The work spans the whole pipeline — from RF front-end sample handling, through acquisition and tracking loops, to the position/velocity/time solution — with most of my time spent in the tight loop between algorithm design and fixed-point implementation.

Building correlation engines and other DSP blocks in VHDL for GPS and adjacent receivers. Code/carrier generators, numerically controlled oscillators, reconfigurable correlators — the hardware that makes a receiver actually track signals at the sample rate.

• US 9,124,356 — Reconfigurable correlator for a navigation system
• US 8,934,384 — Packet-based I/O interface for a correlation engine

Bringing algorithm prototypes onto embedded targets without losing the answer. I care about cycle budgets, memory behavior, and keeping the real-time implementation bit-matched, or at least explainably close, to the MATLAB reference.

Making GNSS receivers useful in contested RF environments. Adaptive cascaded digital beamforming to null simultaneous weak and strong interferers, PSD-based detection of spoofing signals, and sample quantization that preserves the signal of interest under jamming. Most of my patents are in this space.

• US 10,288,742 / 9,709,681 — Digital beam-forming for GNSS threat mitigation
• US 8,934,859 — Detection of RF signal spoofing
• US 8,923,414 — Adaptive sample quantization

The receiver side of GNSS — correlators, loop design, and the error models that sit on top of them. One of my earlier contributions, from Ohio University, was an ionosphere delay compensation algorithm for single-frequency GPS receivers; it remains the published piece I'm most attached to.

The workflow: prototype the algorithm in MATLAB, validate it against recorded data, translate to VHDL or real-time C, and debug the implementation back against the reference. I've spent enough years on both ends of that pipeline that I tend to design the prototype with the translation already in mind.

Northrop's R&D projects tend to be multi-year efforts where the spec, the team, and the target hardware all evolve. I think about requirements, interfaces, and verification as first-class artifacts, not paperwork. My M.S. in Systems Engineering from Johns Hopkins (2013) is where I picked up the formal side of that.

Most of this came out of graduate research at Miami, Ohio University, and an internship at AFIT — Kalman and particle filter comparisons for autonomous navigation, dilution-of-precision calculations for pseudolites, and laser-SLAM integration with vision-aided inertial. It still shapes how I approach state-estimation problems today.