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Go to Editorial ManagerThis paper proposes a new design of compact coplanar waveguide (CPW) fed -super ultra-wideband (S-UWB) MIMO antenna with a bandwidth of 3.6 to 40 GHz. The proposed antenna is composed of two orthogonal sector-shape monopoles (SSM) antenna elements to perform polarization diversity. In addition, a matched L-shaped common ground element is attached for more efficient coupling. The FR-4 substrate of the structure with a size of 23 × 45 × 1.6 mm3 and a dielectric constant of 4.3 is considered. The proposed design is simulated by using CST Microwave Studio commercial software. The simulation shows that the antenna has low mutual coupling (|S21| < -20 dB) with |S11|<−10 dB, ranging from 3.6 to 40 GHz. Envelope correlation coefficient (ECC) is less than 0.008, diversity gain (DG) is more than 9.99, mean effective gain (MEG) is below - 3 dB and total active reflection coefficient (TARC) is less than -6 dB over the whole response band is reported. The proposed MIMO antenna is expected efficiently cover the broadest range of frequencies for contemporary communications applications.
IoHT has several benefits for real-time smart healthcare, but because of its limited processing power, storage capacity, and self-defense capabilities, security issues are growing. Although newer blockchain-based authentication solutions have strong security features due to their tamper-resistant decentralized architecture, they come with a high resource cost, requiring a lot of processing power, more storage, and time-consuming authentication procedures. As such, these difficulties provide barriers to reaching the ideal levels of scalability and temporal efficiency, which are essential for the efficient functioning of large-scale, time-sensitive IoHT systems. To solve these challenges, this paper presents an authentication approach designed especially for IoHT systems. Our work consists four-phase process, which includes setting, registration, login and authentication, and HERs Exchange data. To enhance both efficiency and scalability, the proposed scheme employs a combination of 3-D map dimensions chaotic-based public key cryptosystems, and blockchain-based, fog computing technologies and IPFS. We simulate the proposed work to implement health electronic record (HER) by the Ethereum platform and solidity language, the simulation experiments were tested using the JMeter tool. Showed that the key generation time for chaotic-based is faster than (ECC)—furthermore, the average latency ≈ 3.7 ms. A security analysis of the proposed scheme was implemented by the Scyther tool. The formal security analysis demonstrated that the proposed scheme is secured against potential attacks and supports the scalability of the IoHT system.
Because elliptic curve cryptography offers a promising trade-off between security and computational performance, the field of current cryptographic techniques has taken a particular interest in it. Two basic digital signature algorithms—the Elliptic Curve Diffie-Hellman Algorithm (ECDH) and the Elliptic Curve Digital Signature Algorithm (ECDSA) are the subject of this performance analysis and comparison. These methods are based on elliptic curve cryptography. The analysis takes into consideration realistic application demands as well as factors like key length and security level. The results provide useful information on trade-offs between performance and security. A list of acceptable ECDSA requirements for digital signatures was used for the comparison. These characteristics are sign, sign/s, no PC verify, no PC verify/s, siglen, keygen, keygen/s, verify, and verify/s.