Both airports are investing heavily in equipment to prevent future flight disruption, it was confirmed on Thursday.
A spokesperson for Gatwick said the airport had spent several million pounds on new defences after flights were grounded on its runway last month.
The airport was repeatedly forced to close between 19 and 21 December after drones were spotted.
The closure caused mass disruption, affecting about 1,000 flights and 140,000 passengers, with people forced to sleep on planes and airport floors.
The army was brought in to help deal with the travel chaos and was not stood down until Wednesday.
A spokesperson for Heathrow said: “The safety of our passengers and colleagues remains our top priority.
“Working closely with relevant authorities including the Metropolitan Police, we are constantly looking at the best technologies that help remove the threat of drones.”
The Israeli-developed Drone Dome system is believed to be among the technologies used at the airport by the army.
The anti-drone equipment can detect and jam communications between a drone and its operator and was deployed on a roof at Gatwick.
The system, which is said to have a range of several miles, uses four radars to give 360-degree detection in order to identify and track targets.
Gatwick and Heathrow have not disclosed the specific equipment they plan to deploy to counter the threat posed by drones.
Sussex Police has been examining relevant sightings by 115 witnesses – 93 of whom are said to be credible witnesses who are used to working in the busy airport environment, including a pilot, airport staff and police officers.
The force publicly apologised to a married couple who were arrested and questioned over the drone activity but later released without charge.
Paul Gait, 47, and his wife Elaine Kirk, 54, said they felt “completely violated” after their home was searched and their identities revealed in the media.
The couple were detained by police at their home in the town of Crawley, West Sussex – just five miles from the runway.
Mr Gait, a father-of-two who works as a window fitter, was known by neighbours to be keen on flying model planes and helicopters.
Additional reporting by Press Association
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