## 1 Introduction  
Many developing technologies (including e-health systems, e-mobility, Industry 4.0, and the Internet of Things, as well as body-area networks) use devices enabling wireless information transfer (WIT) using a radio communication module (RCM) [1, 2, 3, 4, 5, 6, 7, 8]. For such purposes, various technologies, standards, and data transmission protocols are used (cellular networks; wireless body-area networks; RadioFrequency IDentification; Wi-Fi; Bluetooth; ZigBee; Long Range; Narrow Band Internet of Things, etc. ), emitting electromagnetic radiation (EMR) from a broad frequency band of 0.01-60 GHz [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]. Currently, the 2.45 GHz (i.e., 2.400-2.483 GHz) and 5.8 GHz (i.e., 5.725-5.875 GHz) ISM (Industrial, Scientific, Medical) bands are particularly intensively used, with a large number of applications [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]. Therefore, this work focuses on an RCM designed for applications using the 2.45 GHz ISM band. Users of such wearable systems, during their work or daily lives, wear devices equipped with RCM antennas (ARCMs) near their bodies (e.g., near the forearm, arm, head, chest, back or thigh--in the form of \"watches\", bands, pendants, rings, on a belt or in a chest pocket), the operation of which causes local exposure to EMR emitted from adjacent ARCMs [1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15]. The location of WIT devices near the user's body in particular applications is most often determined by practical or ergonomic reasons (so that they do not cause any harm or discomfort to the user) [10; 11; 15]. Of particular importance in this aspect are the rapidly advancing applications of this type of device in the form of a disposable, adhesive plaster (also called a bandage or patch) located on the body [9; 10; 11; 12; 13; 14]. According to international requirements, if an EMR source is located less than 20 cm from a person, it is necessary to assess the electromagnetic impact on the exposed person, parameterized by the specific absorption rate (SAR) coefficient values, usually determined on the basis of relevant standardized computer modeling [16; 17]. The SAR coefficient is defined by relevant safety guidelines such as the time derivative of the incremental energy consumption by heat, absorbed by or dissipated in an incremental mass, contained in a volume element, of a given mass density of the tissue, expressed in watts per kilogram (W/kg) [17]. It is also well known that the proximity of physical objects, including a human body, may have a significant impact on the performance of an antenna, compared to how it functions in free space [7; 10; 18; 19]. Various parameters are used to characterize antenna performance, such as antenna gain, resonant frequency, and reflection of emitted EMR [7; 10; 11; 18; 20]. International regulations and relevant standards in this field are silent on which models of the human body are to be used for such purposes. The IEC/IEEE 62704-1:2017 standard allows high-resolution or simplified human body models to be used, specifying only the need to use appropriate dielectric parameters of tissues and the resolution of models [16]. This standard recommends the following: when choosing anatomical models for a dosimetric simulation, the proportions of the body, the accuracy of the tissue distribution, and the geometrical resolution should be considered in order to correctly render the human model for calculating the local exposure. In addition, the selected models shall be representative for the target population with respect to age class, body height and mass, etc. No reference models have been published so far, so various models of the human body or its relevant parts are used in the investigations to model all these groups [7; 10; 11; 15; 18; 20; 21]. The published research results usually use anatomical or simplified models, very rarely both, and only for a single, specific location of the WIT device [7; 10; 11; 15; 18; 20; 21].