Elizabeth Mokrousova, Applications Project Coordinator

The majority of the world’s population is currently hunkering down in their homes to slow the spread of COVID-19. Governments and officials from around the world have adopted a myriad of new strategies to help prevention efforts, from employing the capabilities of AI (artificial intelligence) for tracking software that identifies people with a fever, to 3D-printers used to create hands-free door openers and face shields. Now more than ever, a great deal of emphasis is placed on finding new solutions to problems with the use of existing technology.

On March 15 of this year in Spain, a booming voice suddenly echoed around a group gathered together for an event. The voice was that of a police officer commanding the group to disperse and go home in an effort to enforce social distancing. The twist is that the police officer and his entire department never ventured outside. They were in their office miles away. A few days later, the same scenario occurred in France, and soon people from the United States in Georgia, Florida, and New Jersey heard a similar message from similar disembodied voices. In North Dakota and the Dominican Republic, several families were able to receive food delivery packages right to their door without any human contact whatsoever. In New Delhi, families living in quarantine were supplied medicine without seeing or speaking to any medical professionals in person. Officials in Wuhan, China were able to spray entire public areas with disinfectants without deploying any employees into the field in an effort to prevent further spread of the virus. All of this was possible with one small but powerful technology – drones.

Drones, also known commercially as Unmanned Aerial Vehicles (UAVs) or Small Unmanned Aircraft Systems (SUAS), have come a long way since their early adoption as film gear for movie productions and recreational flyers for hobbyists. Those disembodied voices projecting from thin air were really just pre-recorded messages played from a speaker fitted into a drone flying around a densely populated area. Officers are able to identify crowds that necessitate commands to disperse with the use of a drone’s live feed camera. Depending on the drone model, up to 5kg in payload can be attached, making it possible to deliver food and medical supplies to areas and families in need. Spray drones are commonly used in agricultural applications to spray fertilizer or pesticides over a field, and some can carry up to 6 gallons of liquid product in a spray nozzle attached to the back. Officials in China used this same technology to load a drone with disinfectant solutions that were sprayed over targeted areas.

UAV carrying medical supplies. Image courtesy of Adobe Stock.

Most drones operate in the ISM (for Industrial, Scientific and Medical) radio band. This band and its frequency ranges are designated by the government for industrial, scientific, and medical applications. The only real restriction is that its use can’t affect public safety. You most likely use two major ISM band frequencies in your own home every day when you turn on the Wi-Fi, which operates in the 2.4 GHz or 5 GHz ISM band. Mini-Circuits offers several designer kits with LTCC (Low Temperature Co-Fired Ceramic) parts specifically made for the ISM band. Filter Designer Kit K1-LTCC-WBZ+ and Directional Coupler Designer Kit K2-LTCC-WBZ+ are comprised of parts perfect for drone applications due to their lightweight design and small size, two critical parameters for small and mighty gadgets.

Blueprint layer rendering of a drone. Image courtesy of DJI.

Drones use a combination of sensors, cameras, antennas, GPS and more to gather and transmit information to the crew on ground. The data collected by the drone allows the flight controllers to control its position, altitude, and even the air pressure. As drone models advance, more types of detailed information is becoming available to operation crews, aiding in speedier operations. RF communication is essential to drone operation as it links the brains of the operation (the crew/control person on ground) with the drone itself. This communication is made possible with the use of filters and couplers, which are part of the transceiver. True to its name, the transceiver is used to simultaneously transmit and receive signals between the operators on ground and the vehicle. The antennas on the drone picks up on FM and AM waves carrying random cellular noise. The filter is used to isolate the drone commands and filter out any additional signals. Couplers are used to help verify and monitor the drone’s transmit power level.

The Mini-Circuits ISM band filter and coupler kits provide drone designers a variety of specially selected components for prototyping, eliminating the need to pick and choose components based on rigorous, time consuming research. The K1-LTCC-WBZ+ and K2-LTCC-WBZ+ kits offer different size options to best fit the needs of the designer’s application. Fire fighters, news broadcasters, search and rescue teams, and geologists are just a few of the types of professionals that have benefited from the use of drones in the last few years, and COVID-19 is not the first medical crisis where drones were put to the test. In 2019, researchers deployed spray drones onto rice fields in an effort to prevent the reproduction of mosquitoes carrying Malaria in Zanzibar, Tanzania.

To prevent the misuse of this incredibly valuable technology, the FAA (Federal Aviation Administration) and FCC (Federal Communications Commission) both rolled out rules and regulations in 2016. RF jamming is used by the military and select federal agencies to enforce security where drone flight is prohibited. Select states and local law enforcement are also granted regulations to jam the signals of drones in areas where they pose a potential threat. These RF jamming systems command drones to land or “go home” to their crew. Mini-Circuits has provided customers with products that are not only designed into drones but also into systems used to protect against illegal drone attacks. Mini-Circuits proudly supports the United States government and military in various applications, including aircraft and radio defense. We are strongly committed to providing excellent service to our customers, especially during the global COVID-19 pandemic and are proud to offer convenient and cost-effective solutions for such critical applications.  

A firefighting drone in action. Image courtesy of Shenzhen JTT Technology Co., ltd.