Photo: Parrot
Every ounce counts on a drone. While a larger ground plane on a GNSS patch antenna improves its performance, the additional size increases weight — an unacceptable tradeoff.
The antenna’s location on the drone is another factor. It must be distant from motors and other electronic components that generate interference, which undermines positional accuracy. But remote locations are often off-limits because the antenna’s weight in those spots would disrupt the delicate balance drones require.
Drone-maker Parrot took these factors into consideration when choosing a GNSS antenna for its ANAFI USA drone. Although it weighs just 500 grams, ANAFI USA is designed to operate in winds up to 53 km/h.
To meet these challenges, Parrot chose the Taoglas DSGP.1575.15.4.A.02, a passive patch antenna that supports GPS L1 and Galileo E1. At 3.3 grams and 4 mm high, with a 15-mm2 footprint, the DSGP.1575 is designed for ultra-compact devices.
Key customers
High GNSS accuracy and reliability are critical for Parrot customers such as the French military, which recently ordered 300 ANAFI USA drones for reconnaissance and intelligence missions by its conventional and special forces.
Manufactured in the United States, ANAFI USA has also been selected by U.S. federal government partner organizations as part of the Blue sUAS project — the only UAV from a non-American drone manufacturer to be commercialized on the GSA Schedule, the buying platform of the U.S. military and civilian government agencies.
Police departments, federal agencies and firefighters in the United States and other countries also use ANAFI USA. The drone is also used for surveying, inspection and other commercial enterprises.
Tuned on a 50×50 mm ground plane, the DSGP.1575 operates at 1575.42 MHz with a 2.59 dBi gain. It uses ceramic materials — suitable for UAV applications because drones spend most of their time flying parallel with the horizon, a position in which ceramic antennas collect sufficient GNSS signals to meet performance requirements.
The DSGP.1575’s light weight and energy efficiency enable the ANAFI USA to carry bigger payloads and fly longer, up to 32 minutes compared to the consumer model’s 25 minutes.
“We chose Taoglas because of the quality of their antennas and their ability to tune an existing antenna in the mechanics of the product and to make it on a large scale for mass production,” said Meryam Abou El Anouar, Parrot technical leader for RF and Connectivity. “They are also known for their great experience with the GNSS propagation specificities as multipaths, so that is helpful when you try to achieve good GNSS accuracy.”
Taoglas provided Parrot with design and testing support in its design centers, as well as making regular visits to Parrot’s facility in Paris.
“Our engineering team managed to carry out tests at antenna and system levels,” said Baha Badran, Taoglas Global Antenna Technology director. “This includes passive antenna testing, in-chamber active antenna testing and GPS field testing of the drone. Each of these tests was carried out to ensure optimum GPS system performance was achieved, to give the highest possible positional accuracy for such an application.”
The support also helped Parrot minimize the cost and lead time for bringing the ANAFI USA to market.
