Communication between UAV Swarm and Ground Control Station for Real Time Surveillance

Abstract

To provide a better solution in these areas compared to existing standard, “IEEE 802.11ah HaLow” was standardized by making amendments to IEEE 802.11 in 2016. It is the first sub 1 GHz WLAN standard with characteristics of multiband multimode of operation, ranging from 1 MHz to 16 MHz up to 10 modes in each respectively, improved physical and link layer, long-range and energy efficient communications. In the proposed communication scenario, Multiple Unmanned Aerial Vehicles (UAVs) are communicating with Ground Control Station (GCS). All of the UAVs have a Bi-directional communication link with the GCS and among themselves creating a mesh network. Each of the UAV transmits video surveillance data to the GCS for processing along with control messages but all the UAVs share only control messages among themselves. Multiple user scenario required multiple access system that allows multiples users to transmit data without any interference. TDMA, FDMA and CDMA are the options available for channelization purpose and CDMA is selected due to better performance (allowing multiple users to transmit data simultaneously utilizing the complete band without any ISI) as compared to FDMA and TDMA. Multicarrier CDMA for IEEE 802.11ah is simulated for performance curves and data rates. Control data has smaller size as compared to video transmission data but more importance i.e. control data provides a reliable connection between different entities in the scenario. Without reliable connection there can be no data transmission. As different data rates are required for control data and video surveillance data, multicode (multiple CDMA spreading codes) concept is proposed in this scenario to improve the data rates suitable for multiple links. Multimode Multiband in Multicarrier CDMA provided with many modes with different range of data rates. A comparison based on similar data rates and best performance was made with reduced the modes to few that were simulated for Multicode Multicarrier CDMA in AWGN (Additive White Gaussian Noise) for IEEE 802.11ah. Complete performance analysis and data rates comparison for IEEE 802.11ah and both of the proposed methodologies are presented along with future work