Jamming-resistant doesn't mean one thing

I was a Counter-IED and Electronic Warfare Officer, and "resistant to jamming" is the phrase I was trained to take apart rather than accept. It showed up again in an April 2026 Defense One story about Operation Clear Horizon, a special-operations exercise at Eglin Air Force Base that deliberately copied the drone tactics Ukraine used against Russia. The exercise itself ran in September, and the task force's own December 2025 progress update already references it as a completed event, which is how I place it in September 2025 rather than a year later.

What actually got flown over Eglin

Reporter Patrick Tucker got Brig. Gen. Matt Ross, who leads Joint Interagency Task Force 401, the Pentagon's counter-drone clearinghouse, on the record about the attacking drone mix at the Sea-Air-Space symposium. Here is Ross, quoted in full:

They flew drones that were regular [radio-frequency], commercial drones. They flew drones that had directional antennas on them so they're harder to jam, drones that were frequency hopping so they have a more resilient connection

Tucker adds that the resilience was "against electromagnetic attack," and that Ross made these remarks at the symposium. Ross continued, describing the size range and two more control methods entirely:

They went up to Group 3 drones

We used fiber optically-controlled drones…We used drones controlled by LTE, the cellular network,

The LTE link, Tucker reports, let operators sitting in Colorado fly against targets in Florida, which he calls a first for the U.S. military. Tucker's own summary of the mix, before any of those quotes, is the line that caught my attention: "the special operators used a wide range of drones, from small to large, and many that were resistant to jamming and radar." That is the reporter's framing, not Ross's words, and it is doing more work than one sentence should. It puts a frequency-hopping commercial drone, a drone with a directional antenna, a fiber-optic drone and an LTE-controlled drone into the same bucket. An electronic warfare officer looking at that list sees at least three different engineering problems wearing the same adjective.

A frequency-hopping link is still an RF fight

Start with the one that sounds the most like a clean counter to jamming: frequency hopping. The public Electronic Warfare and Radar Systems Engineering Handbook, published by the Naval Air Warfare Center Weapons Division, defines the jammer's two main options against any receiver that changes channel, and it is blunt about what frequency agility does to the simpler one, spot jamming:

Occurs when a jammer focuses all of its power on a single frequency. While this would severely degrade the ability to track on the jammed frequency, a frequency agile radar would hardly be affected because the jammer can only jam one frequency. While multiple jammers could possibly jam a range of frequencies, this would consume a great deal of resources to have any effect on a frequency-agile radar, and would probably still be ineffective

So a hopping link really does beat a jammer sitting on one channel. But the handbook's next option, barrage jamming, is built for exactly this case, and it gives a cost, not a wall:

The jamming of multiple frequencies at once by a single jammer. The advantage is that multiple frequencies can be jammed simultaneously; however, the jamming effect can be limited because this requires the jammer to spread its full power between these frequencies. So the more frequencies being jammed, the less effectively each is jammed.

The handbook attaches a worked figure to that paragraph: concentrating a jammer's full power into one frequency and then spreading it so that only 14% of the jamming energy lands in a given receiver's bandwidth costs 8.6 dB of jam-to-signal ratio. That is a real, quantified trade, not a hand wave, and it is one a jammer operator can choose to pay by adding power or accepting a shorter effective range. The handbook also defines a third option, swept jamming, "a jammer's full power is shifted from one frequency to another," which reaches every channel in turn but "does not affect them all at the same time, and thus limits the effectiveness of this type of jamming."

The handbook is written for radars, and I want to be precise about what carries over and what doesn't. I don't have a public source describing how JCREW- or NINJA-family jammers specifically handle a frequency-hopping drone link, and I'm not claiming one does or doesn't. What does carry over is the general physics: a receiver that changes frequency denies a jammer the free option of parking all its power on one channel, and forces a choice between spreading that power thin (barrage) or chasing the signal with gaps in coverage (swept). I made the same kind of one-way-link argument from this handbook for drone jamming in Report 161; this is the same handbook, extended to the next chapter.

A directional antenna is a gain number, not a cloak

The second quote in Ross's list, the directional antenna, is a different kind of claim, and the handbook's basic antenna-gain description explains why it is harder to jam without making the link invisible:

Radars use directional antennas to channel most of the radiated power in a particular direction. The Gain (G) of an antenna is the ratio of power radiated in the desired direction as compared to the power radiated from an isotropic antenna

Concentrating a link's own transmit power toward the intended partner, operator to drone or drone to operator, raises the power a jammer has to beat along that same direction, exactly the way a radar's directional antenna raises the power a target has to see through. That is a real advantage. It is also, by definition, directional: the handbook separately defines a NULL as "the directions of minimum transmission (or reception) of a directional antenna," and its description of a mechanically scanning "spinner" antenna notes that when the emitter itself uses a scanning directional antenna, "both beams must point at each other for maximum sensitivity, which is a low probability occurrence." A gain pattern that makes a link harder to jam in one direction is, by the same geometry, weaker in the directions it isn't pointed. None of the handbook's drone-specific numbers exist in public, so I'm stating this as the general property gain gives any directional link, not as a claim about what actually happened to any drone at Eglin.

Two drones that left the fight the jammer was built for

The last two items on Ross's list aren't RF-power contests at all. A fiber-optic drone has no radio link between operator and aircraft to jam, which is why I've written about it three times already on this beat: in Report 002, Report 007, and the high-power-microwave kill described in Report 014. An LTE-controlled drone is still radio, but the receiver it depends on is a cell tower, not a dedicated link between the operator's controller and the aircraft. Defeating that moves the problem onto the public cellular network the drone is borrowing, which is a different kind of fight than overpowering a point-to-point link, and none of my sources here describe how, or whether, JIATF-401 proposes to do it.

What I could not confirm

No source here says which of the four types the exercise's defenders actually defeated, or how. Ross's public remarks were about tracking, data fusion, and procurement lessons, not about which jamming or kinetic method beat which drone type. I found no after-action figures.

The year of the exercise rests on cross-referencing two sources, not a dated primary. Defense One gives only "a September exercise"; I place it in 2025 because the task force's own December 19, 2025 public update already discusses lessons from Operation Clear Horizon as settled. I did not find a source that states the day or the year directly.

The antenna-gain and jamming-type physics here is general public-domain EW theory, applied by analogy. The handbook describes radars, not JCREW, DRAKE, NINJA, or any drone-specific jammer, and gives no frequency, power, or range figures for any fielded system. Nothing in this report describes how to defeat, degrade, or evade any specific jammer or drone.

Whether Tucker's "many that were resistant to jamming and radar" includes the fiber-optic and LTE drones, or only describes the RF types, is not specified in the source.

The signal

"Jamming-resistant" is being asked to describe four different engineering situations: a frequency-hopping link, which is still an RF fight with a quantified cost on the jammer's side; a directional antenna, which is a gain pattern that helps in one direction and not others; a fiber-optic link, which has left the electromagnetic spectrum entirely; and an LTE-controlled drone, which has handed its link to a cell tower instead of a jammable point-to-point radio. A single exercise flying all four at once is good training. Reporting all four under one adjective is the part worth correcting. When the next "jamming-resistant drone" headline shows up, the useful question isn't whether it's resistant. It's which of these four problems it actually is, because the counter is different every time.