Frequency dependence of on-body channels with top-loaded monopole antennas in the range of HF to UHF

Abstract

In recent years, body-centric wireless communications have become an active area of research due to their various applications. Whereas UHF bands are subjects of interest especially in Europe, relatively low frequency bands below several megahertz are also in researchers' and corporations' interest especially in Japan. Thus, all of the candidate frequencies are in an extremely wide range. Our purpose is to bring objective and unified idea on the frequency characteristics of body-centric wireless communication channels with small wearable antennas. In this paper, we numerically observe the open voltage at several receiving antennas, and examined three different postures.

A Study of Factors Affecting Wrist Channel Characteristics for Walking Postures Using Motion Capture

“…This paper presents a study of on-body channels during walking and comparison is made with other investigations, [1][2][3][4][5][6][7][8][9][10]. In [1][2][3][4] BAN studies were based on measurements on humans while [5] relied solely on EM simulations on a phantom.…”

“…BAN channel variation during walking has been studied for a single model in [1], [2], [4][5][6][7][8] and for a population of models in [3], [9], [10]. While [9] showed that a population with similar height had comparable forward transmission (S 21 ) levels for a given walking stance, differences between individuals were not negligible and could be up to 10dB.…”

“…In [1][2][3][4] BAN studies were based on measurements on humans while [5] relied solely on EM simulations on a phantom. [6][7][8][9][10] included both measurement and simulation and [5][6][7][8] utilized proprietary numerical human phantoms and the animation package 'Poser' where physical stances were digitally posed and compared to video frames from the measurement.…”

“…However, in [5][6][7][8], it was difficult to ensure that the walking movement generated by posed phantoms was sufficiently close to that of the human under test. In [6] attempts were made to address this problem by having the human imitate the walking stances of the Poser model.…”

Small Antennas Used in the Vicinity of Human Body

“…The antenna has low-profile dimension (4-mm thick) and has no matching structure for simplicity. [7].…”