Welcome to Stephens Labs!


R&D and prototyping


As an R&D and rapid-prototyping company, we work with clients to help define systems and deliverables, and provide end-to-end development. In particular, we specialize in:
  • Customized navigation, geolocation, and RTLS solutions
  • Telecommunication systems design, analysis, and simulation
  • Definition of complex algorithms, their analysis and software embodiment
These solutions are developed as part of a full system design process:
  • Product requirements definition and flowdown to engineering requirements
  • Design subsystem components via analysis and performance/cost tradeoffs
  • Provide project management on digital/RF subsystem design and development
  • Develop product software
  • Provide integration and test, including field deployment and follow-on spiral development

Core competencies


Our core competencies include
  • Techniques
    • Estimation: Kalman, sigma-point, SRIF, and particle filters
    • Control systems: phase-locked loops, and other controller feedback
    • Info theory: channel coding and modulation evaluation and optimization; BEP analysis.
    • Communication: phy/link/mac layer design; channel mitigation
  • Modeling
    • RF and optical propagation, including multipath/diffraction, media (dielectric/atmospherics including ion/solar plasma), and antenna/fiber channels.
    • Sensors: inertial (acc, gyro), mag, laser scanning, optical/visual systems
    • Subsystems: GPS and RFID
    • Physical systems: vehicle dynamics, satellite orbits, surface physics sensors
  • Analysis and simulation
    • Analysis via custom tools, Matlab, SPW.
    • Visualization
  • End-to-end development
    • Systems engineering flowdown, cost trades, and project management
    • Proposal drafts: DOD/DARPA, SBIRs, secret/SBI clearances (reinstatable)
    • Integration and test of complex systems
    • Software systems (linux/android, java/C/C++/C#)
For more information on these techniques, please follow sidebar on left.

Past customers and projects


Past customers/projects include:
  • NASA/JPL: deep space receiver design (phy/link layers: acq, tracking algorithms)
  • TRW/NG: geolocation from MEO satellite constellation; satellite broadcast radio
  • Motorola: satellite and terrestrial communication systems
  • John Deere: Navigation for robotic systems, including GPS-denied areas, synthetic-aperture radar mapping and location, and fusing multiple sensors in deliverable software for commerical/military products
  • RFID location using multiple receive points and both phase-coherent beamforming and RSSI

For more examples of past projects, please follow sidebar on left.