Human-body communication (HBC) has increasingly gained attention from academia and industry. Most current works focus on characterizing the use of human-body tissues as a physical medium to enable reliable communication. However, designing coupling hardware and communication circuits for reliable data transmission (e.g., high throughput and low latency) is a demanding task, especially for achieving a compact full electronic implementation. For this purpose, there are few commercial devices, mainly differential probes and balun transformers, employed with electrical analysis instruments such as oscilloscopes and vector network analyzers. Although these devices are widely used, they are expensive and are difficult to miniaturize and integrate into real-world HBC-specific applications (e.g., data security). This article presents a low-cost electronic system that transfers collected data using a secondary channel: the ionic environment (the primary channel would be the wireless environment). We design an electronic system as an experimental setup for studying HBC, allowing the communication between instruments, sensors, and actuators by human-body tissues. The experimental evaluation of the proposed system follows (i) a phantom composed of saline (0.9%) and (ii) a real human forearm through adhesive surface electrodes.

Singular Spectrum Analysis (SSA) is a non parametric approach that can be used to decompose a time series into trends, oscillations and noise. In online applications, the SSA algorithm must be recalculated for each new sample available. The so called Causal SSA have been used in this context. This paper aims to contribute to the application of Causal SSA as an indicator for trading rules design by means of comparing them to previously proposed ones based on classic indicators. Using historical time series from some of the major Brazilian stocks, different simulations are carried out. Some performance metrics are applied along with several statistical tests, thereby supporting a detailed analysis of the experimental results obtained. The results analysis indicates that, no matter what technical trading rules, it is worth to apply the SSA method rather than classic approaches.