When Wireless Technologies and Drones Soar
Posted 08/02/2016 by Peiju Chiang
When I walked the show floor at CES 2016, I knew right then and there that drones would become one of the hottest technologies of 2016. I could not go a few steps without seeing one hovering in the air. There were drones as small as the size of your palm and drones that aimed to carry a person in flight. Even the heavy-weights like Intel, Qualcomm, and NVIDIA, had joined the fray1. Since then, we have seen them disrupt the sports world with the emergence of the Drone Racing League and heard of Amazon’s plan to utilize them for package deliveries. Individuals started posting amazing Internet videos captured by drones from locations not accessible before online. And the growing popularity of live broadcast and real-time video will continue to drive broad adoption of drones. All of this is made possible because of wireless technology, which I will explore in this blog.
Before diving into the technology, it is important to understand that there are two kinds of drones: one that comes with a camera and one that requires separate mounting of a gimbal and camera. The former option is generally less costly and targeted towards consumers and amateurs, while the latter gives you the freedom to customize and is targeted towards semi-professional and professional users. Both drones transmit the views captured by the camera wirelessly down to the remote control. This wireless technology sends these real-time views from the camera back to the remote control with minimal latency, so you can accurately navigate the drone while having precise control of the shot you want to take with the camera. Most drones advertise a range of up to 1 km and typically use wireless technology in the unlicensed 2.4 GHz band. In order to boost the range, drones and their remotes are equipped with high gain antennas. 2.4 GHz signal has good free space propagation characteristics to make this range possible. Due to limited bandwidth of the wireless link, the video from the camera is compressed to reduce bandwidth and minimize latency before being sent out to the remote control, while keeping the captured video in the memory card unaffected. Although this is the main wireless video use case in drones, there are others worth mentioning.
For those drones that require a gimbal and separate cameras, an HDMI® cable is needed to connect the camera and the drone. While the gimbal provides the ability to adjust the angle of the camera, the HDMI cable still limits its freedom to rotate continuously. The remote control has separate knobs for camera movement which requires the operator to pay close attention to how much more the camera can rotate. 60 GHz wireless technology is the ideal solution to address this problem because of its high-bandwidth and ultra-low latency. This solution is commercially available today.
Last but not least is the connectivity between the remote control and display device that shows the views from the drone. For remotes with a built-in screen, there is no need for additional displays. Those without a display mostly utilize smartphones and tablets. In order to be compatible with the available mobile devices, the remote control must offer Wi-Fi compliant technology to interface with mobile devices.
Looking into the future, drones may need additional wireless technology to make them smarter and more autonomous. Wireless sensing and detection is definitely a possibility, but this is a topic for another blog.
1 http://dronelife.com/2016/03/14/drone-companies-the-four-big-chip-makers/