Frontier TechAnalysis

A Diamond Sensor Moves Toward Aircraft Navigation

MIT Lincoln Laboratory is working with industry on a flight-tested sensor that reads magnetic direction as well as strength, adding clues for navigation when satellite signals are disrupted.

Published November 10, 2026Analysis / Frontier Tech / Experimental Systems

Massachusetts Institute of Technology (MIT) Lincoln Laboratory is working with Frequency Electronics Inc. (FEI) to turn a diamond magnetic sensor into equipment industry can build and integrate aboard aircraft. Its November 9 account describes a prototype already tested in flight and the work now needed to improve performance, manufacturing and size. 1

The approach, called magnetic navigation (MagNav), compares measurements with a map of magnetic variations associated with Earth's crust. Lincoln's sensor measures both field strength and direction. Those extra directional clues can help distinguish locations that look similar when only strength is measured, giving navigation software more information about where an aircraft has traveled. 1,3

For an aircraft facing disruption of the Global Positioning System (GPS), a magnetic map offers another source of position information. The signal comes from the ground beneath the route. Making it useful requires the aircraft's measured pattern to agree closely enough with the surveyed one, while accounting for the vehicle's own magnetic disturbances. Civil operators would also need performance and integration evidence suited to their aircraft and routes. 3,5

The industry effort predates this week's update. FEI announced a Leidos subcontract on March 27, 2025, covering a multiyear program to design, prototype and test a nitrogen-vacancy diamond magnetometer. Lincoln dates the technology's transfer to FEI to 2025. The current work concerns developing that sensor toward wider use, with an integrated chip-scale version described as a longer-term goal. 1,2

What the diamond measures

The useful part of the diamond is an engineered imperfection. A nitrogen atom takes the place of a carbon atom beside an empty site in the crystal. This nitrogen-vacancy (NV) center has electron spin states that respond to a magnetic field. A collection of such defects turns a small piece of diamond into a sensing material. 4

In an established sensing method, laser light prepares the spins, and microwaves probe the frequencies at which they change state. Changes in the diamond's fluorescence reveal those resonances. The separation between resonance frequencies carries information about the magnetic field. The optical measurement gives the instrument a way to read a physical response occurring inside the crystal. 4

NV centers can point along four directions fixed by the diamond lattice. Combining measurements along those directions reconstructs the field's vector: its strength and orientation. A 2018 paper from MIT and Lincoln Laboratory demonstrated a way to track paired resonances while reducing the influence of temperature changes. Those earlier laboratory results explain the sensing principle; the current aircraft hardware has a separate field-testing history. 4

For navigation, steadiness matters as much as sensitivity. An aircraft may take time to cross a broad magnetic feature. If the sensor's reading drifts during that interval, navigation software can mistake the changing instrument for a changing landscape. Lincoln's June 2026 conference abstract identifies low-frequency stability and a rigid connection between the magnetometer and an inertial sensor as essential requirements. 3

Tests in the air

Lincoln's November account describes flight tests in 2022, followed by further tests in 2025 and 2026. Its June conference abstract describes helicopter proof-of-concept testing and work aboard a turboprop in more demanding conditions. These steps test whether a sensor that works on a controlled bench can preserve useful measurements while carried by an aircraft. 1,3

According to Lincoln, the 2022 tests navigated through regions with little change in field strength and produced a twofold accuracy improvement over scalar systems in more typical conditions. The release gives neither an absolute position-error figure nor a detailed comparison protocol. Judging the practical advantage would require those details, including the routes and conditions behind the relative figure. 1

Magnetic measurements can work with inertial measurements, which track motion through the aircraft's own instruments. Inertial estimates accumulate error over time. Matching the observed magnetic pattern to the map can help constrain that drift. The connection between the instruments, their orientation and the stability of the magnetic reading all affect how much confidence the software can place in a correction. 3

The map and the aircraft still matter

MagNav operates independently of the satellite radio link targeted by a GPS jammer. Its measurements still have to be separated from magnetic disturbances produced by the vehicle carrying it. Map coverage and resolution also shape how precisely a measured pattern can be placed on the ground. MITRE's assessment of complementary navigation identifies platform calibration, signal processing and high-quality maps as continuing development needs. 5

Adding directional information can improve the evidence available to the navigation software. The whole system still needs to be assessed together: sensor, map, inertial instruments, compensation software and installation. For an operator, the cost of fitting and calibrating equipment on a particular aircraft belongs alongside the sensor's purchase price and measured navigation performance. 3,5

“Our long-term vision is to build an integrated chip-scale version of this technology,” project lead Linh Pham said in Lincoln's published account. The immediate engineering goals are improved performance, easier manufacturing and lower size, weight and power. A smaller instrument could broaden the platforms able to carry it; production yield, installation work and route-level accuracy will determine the practical case for adoption. 1