1 Vol.:(0123456789) Scientifc Reports | (2022) 12:14128 | https://doi.org/10.1038/s41598-022-17550-z www.nature.com/scientificreports Analysis of integrated UWB MIMO and CR antenna system using transmission line model with functional verifcation P. Prabhu 1* , Malarvizhi Subramani 1 & Kyung‑sup Kwak 2* This paper discusses the equivalent circuit model and functional verifcation of an integrated antenna system as its main focus. The integrated antenna system consists of two independent antenna systems, namely the Cognitive Radio antenna and the Ultra Wide Band Multiple Iinput Multiple Output antenna. This article is split into two parts: The frst part discusses the equivalent circuit of an integrated antenna system by optimizing the RLC values. The developed lumped equivalent circuit model produces the NB resonant frequencies, which is the same as the S‑parameter obtained through EM simulation. The second part of this paper aims to discuss the experimental verifcation of an integrated CR antenna system with Bayesian learning‑based spectrum sensing algorithms using Universal Software Radio Peripheral devices. Real‑time sensing and communication functionalities are visualized in the LABVIEW monitor. The integrated antenna system is fabricated and measured after the simulation. Recently, MIMO technology, Cognitive Radio (CR) technology, and integrated independent antenna systems attracted antenna researchers due to efective performance, compact size, low cost, and easy implementation. In 2002, the Federal Communications Commission (FCC) proposed many solutions to improve spectrum utilization efciency. According to the usage of idle channels and spectrum white space, they are divided into three groups. Tey are namely spectrum reallocation, sharing, and leasing. Spectrum sharing is classifed as open spectrum sharing, hierarchical spectrum sharing, and dynamic spectrum allocation. In addition, hierarchical spectrum sharing is accomplished in two ways. Te frst way is spectrum underlay, and the second way is spectrum overlay. In the spectrum overlay method, the Cognitive Radio (CR) technology is employed to exploit free channels or gaps in the spectrum. In a wireless environment, the licensed spectrum is a license fee paid by the main user, but some users have not always used the licensed spectrum. Hence, CR technology allows you to search for idle channels in the wireless environment regularly. If the cognitive system recognizes the free channel, the second- ary user will use it for other wireless communication applications until the primary user needs it. Whenever the primary user tries to occupy a spectrum that was previously emptied, the secondary user changed to another working frequency or the communication will end until the next spectral hole is identifed. Te CR system utilizes the UWB antenna and Narrow Band (NB) antenna for sensing and communication purposes, respectively. Con- sidering the structure of the antenna, the planar monopole antenna has the advantages of being easy to integrate with a fat structure, easy to manufacture, and small in appearance, so it has been widely used in CR technology. Sensing UWB antennas need to operate at frequencies of 3–10.6 GHz or higher than 10.6 GHz, but the FCC licenses frequencies up to 10.6 GHz, and the FCC does not license spectrum at frequencies afer 10.6 GHz. Te single band or multi-band NB communication antennas used for communication purposes. In recent years, re- confgurable UWB/NB antennas have been used in CR technology. As mentioned above, the sensing antenna can sense multiple white spaces in the frequency spectrum atone time. Terefore, the re-confgurable NB antenna needs to be continuously switched from one frequency to another frequency to communicate through identifed multiple white spaces. Tus, the design of a multi-state switching re-confgurable antenna is very complicated. Similarly, recently, research on MIMO antennas has also been rapidly developed. Multiple Input Multiple Out- put (MIMO) technology is resolving multipath fading and improves the system’s channel capacity using exiting spectrum 1,2 . Furthermore, UWB MIMO antenna 3,4 , Band notched UWB antenna 5–9 , Re-confgurable Cognitive OPEN 1 Department of ECE, SRM Institute of Science and Technology, Katankulatur, Chennai, Tamilnadu 603203, India. 2 UWB Wireless Communications Research Center, Inha University, Incheon 402-751, South Korea. * email: prabhusrmist2020@gmail.com; kskwak@inha.ac.kr