Bluetooth low energy (BLE) is a personal area network (PAN) technology that has been widely implemented in various Internet of Things (IoT) services. BLE defines a connectionless communication method based on request–response to more effectively adapt to services with high flexibility requirements. This communication method can be divided into three steps: the neighbor discovery process (NDP), scan request, and scan response. First, the NDP enables a device known as the scanner to discover another device known as the advertiser nearby. In the second step, the scanner sends a scan request to the advertiser which, after receiving the scan request, sends a data packet in response. Unfortunately, this method is flawed in that the simultaneous discovery of an advertiser by multiple scanners would cause the request packets they send to collide with high probability. In fact, these collisions may always occur when scanners continue to discover common advertisers. To solve this problem, various schemes have been proposed to reduce the probability of a collision. However, these schemes are only suitable for application scenarios with fewer scanners; when more scanners are present, their latency and energy consumption increase rapidly. This prompted us to propose a scheme to improve the performance of the connectionless communication method. In addition, convex optimization was used in the proposed model to minimize the transmission delay and energy consumption. The final simulation results prove that the proposed scheme effectively reduces the delay and the energy consumption when many scanners are involved.
This research was supported by the MSIT (Ministry of Science and ICT), Korea, under the ITRC (Information Technology Research Center) support program ( IITP-2020-2018-0-01431 ) supervised by the IITP(Institute for Information & Communications Technology Planning & Evaluation).Byeong-hee Roh was born in Seoul, South Korea. He received the B.S. degree in electronics engineering from Hanyang University, Seoul, South Korea, in 1987, and the M.S. and Ph.D. degrees in electrical engineering from the Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea, in 1989 and 1998, respectively. From 1989 to 1994, he was a Researcher with the Telecommunication Networks Laboratory, Korea Telecom, Seongnam, South Korea. From February 1998 to March 2000, he was a Senior Engineer with Samsung Electronics Company, Ltd., South Korea. Since March 2000, he has been with the Department of Software and Computer Engineering, Ajou University, Suwon, South Korea, where he is currently a Professor. In 2005, he was a Visiting Associate Professor with the Department of Computer Science, State University of New York, Stony Brook, NY, USA. In 2014, he was an Adjunct Researcher with the Agency for Defense Development (ADD), Daejeon, South Korea. Since 2016, he has been the Director of Mixed Reality-Internet of Things (MR-IoT) Convergence Disaster Response Artificial Intelligence (AI) Research Center supported by the Ministry of Science and ICT (MSIT), Korea, under the Information Technology Research Center (ITRC) Support Program. His research interests include mobile multimedia networking, future Internet, military communications, Internet of Things (IoT) platform and services, augmented reality (AR), and mixed reality (MR).
