Meandering Pattern 433 MHz Antennas for Ingestible Capsules

A number of design challenges are associated with in-body devices, especially ingestible capsules, including selection of operation frequency and antenna design. Operation frequency, miniaturization, gain, and interference with the environment and the internal components of ingestible capsules are all challenging factors. In this work, we design and measure the performance of miniature antennas that can be included in ingestible capsules. The meandering pattern designs are implemented with a 433 MHz center frequency which is within one of the industrial, scientific and medical (ISM) bands. The antenna patterns are rolled into cylinders to reflect their configuration inside a capsule. The effects of different antenna design features, environmental dielectric changes, and the battery locations relative to the antenna traces are explored. We show that the optimized antenna can offer acceptable performance even when the center frequency shifts due to the modulation of the dielectric constant of the media and by the insertion of batteries. Both simulations and measurements provide insight into how the meandering antenna should be designed for the desired frequency that can be expanded to other ingestible and implantable systems.

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Vibrotactile Captioning of Musical Effects in Audio-Visual Media as an Alternative for Deaf and Hard of Hearing People: An EEG Study

Standard captioning for the deaf and hard of hearing people cannot transmit the emotional information that music provides in support of the narrative in audio-visual media. We explore an alternative method using vibrotactile stimulation as a possible channel to transmit the emotional information contained in an audio-visual soundtrack and, thus, elicit a greater emotional reaction in hearing-impaired people. To achieve this objective, we applied two one-minute videos that were based on image sequences that were unassociated with dramatic action, maximizing the effect of the music and vibrotactile stimuli. While viewing the video, using EEG we recorded the brain activity of 9 female participants with normal hearing, and 7 female participants with very severe and profound hearing loss. The results show that the same brain areas are activated in participants with normal hearing watching the video with the soundtrack, and in participants with hearing loss watching the same video with a soft and rhythmic vibrotactile stimulation on the palm and fingertips, although in different hemispheres. These brain areas (auditory cortex, superior temporal cortex, medial frontal cortex, inferior frontal gyrus, superior temporal pole and insula) have been consistently reported as areas involved in the emotional perception of music. We conclude that vibrotactile stimuli can generate cortex activation while watching audio-visual media in a similar way to sound. Thus, a further in-depth study of the possibilities of these stimuli can contribute to an alternative subtitling channel for enriching the audiovisual experience of hearing-impaired people.

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